One document matched: draft-ietf-rtcweb-sdp-00.xml


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<rfc category="info" docName="draft-ietf-rtcweb-sdp-00"
     ipr="trust200902">
  <front>
    <title abbrev="SDP4WebRTC">SDP for the WebRTC</title>

     <author fullname="Suhas Nandakumar" initials="S." surname="Nandakumar">
      <organization>Cisco</organization>

      <address>
        <postal>
          <street>170 West Tasman Drive</street>

          <city>San Jose</city>

          <region>CA</region>

          <code>95134</code>

          <country>USA</country>
        </postal>

        <email>snandaku@cisco.com</email>
      </address>
    </author>

   <author fullname="Cullen Jennings" initials="C." surname="Jennings">
      <organization>Cisco</organization>

      <address>
        <postal>
          <street>170 West Tasman Drive</street>

          <city>San Jose</city>

          <region>CA</region>

          <code>95134</code>

          <country>USA</country>
        </postal>

        <phone>+1 408 421-9990</phone>

        <email>fluffy@cisco.com</email>
      </address>
    </author>

    <date day="17" month="September" year="2015" />

    <area>RAI</area>

    <abstract>
      <t>The Web Real-Time Communication <xref target="WebRTC"></xref>
      working group is charged to provide protocol support for direct
      interactive rich communication using audio, video and data between
      two peers' web browsers. With in the WebRTC framework,
      Session Description protocol (SDP) <xref target="RFC4566"></xref> is
      used for negotiating session capabilities between the peers. Such a
      negotiation happens based on the SDP Offer/Answer exchange mechanism
      described in <xref target="RFC3264"></xref>.</t>
      <t> This document provides an informational reference in describing
      the role of SDP and the Offer/Answer exchange mechanism for the most
      common WebRTC use-cases.</t>
      <t hangText="Note"> This SDP examples provided in this document is
      still a work in progress, but it aims to align closest to the evolving
      standards work.</t>
    </abstract>
  </front>

  <middle>
    <section title="Introduction">
      <t>Javascript Session Exchange Protocol(JSEP)
	  <xref target="I-D.ietf-rtcweb-jsep"></xref> specifies a generic protocol
	  needed to generate <xref target="RFC3264"></xref> Offers and Answers
	  negotiated between the WebRTC peers for setting up, updating and tearing
	  down a WebRTC session. For this purpose, SDP is used to construct
	  <xref target="RFC3264"></xref> Offers/Answers for describing (media and
	  non-media) streams as appropriate for the recipients of the session
	  description to participate in the session.</t>
      <t>The remainder of this document is organized as follows: Sections
      3 and 4 provides an overview of SDP and the Offer/Answer exchange
      mechanism. Section 5 provides sample SDP generated for the most common
      WebRTC use-cases.</t>
    </section>
    <section title="Terminology">
      <t>The key words "MUST", "MUST NOT", "REQUIRED", "SHOULD", "SHOULD NOT",
        "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be
        interpreted as described in <xref target="RFC2119"></xref>.</t>
    </section>
    <section title="SDP and the WebRTC">
      <t> The purpose of this section is to provide a general overview of SDP and
      its components. For a more in-depth understanding, the readers are
      advised to refer to <xref target="RFC4566"></xref>.</t>
      <t>The Session Description Protocol (SDP) <xref target="RFC4566"></xref>
      describes multimedia sessions, which can contain audio, video, whiteboard,
      fax, modem, and other streams. SDP provides a general purpose, standard
      representation to describe various aspects of multimedia session such as
      media capabilities, transport addresses and related metadata in a
      transport agnostic manner, for the purposes of session announcement,
      session invitation and parameter negotiation.</t>
      <t>As of today SDP is widely used in the context of Session Initiation
      Protocol <xref target="RFC3261"></xref>, Real-time Transport Protocol
      <xref target="RFC3550"></xref> and Real-time Streaming Protocol
      applications <xref target="RFC2326"></xref>.</t>
      <t>Below figure introduces high-level breakup of SDP into components that
      semantically describe a multimedia session, in our case, a WebRTC session
      <xref target="WebRTC"></xref>. It by no means captures everything about
      SDP and hence, should be used for informational purposes only.</t>
      <figure title="Semantic Components of SDP" anchor="fig.sdp.semantics">
          <artwork><![CDATA[
                                                +---------------------+
                                                |        v=           |
                                                +---------------------+
                +---------------------+         +---------------------+
        ====    |   Session Metadata  |  =====  |        o=           |
        |       +---------------------+         +----------------------
        |                                       +---------------------+
        |                                       |        t=           |
        |                                       +---------------------+
        |
        |
        |                                       +---------------------+
        |                                       |        c=           |
        |                                       +---------------------+
        |       +---------------------+
        ====    | Network Description |   =====
        |       +---------------------+
        |                                       +---------------------+
        |                                       |    a=candidate      |
        |                                       +---------------------+
        |
        |
        |                                       +---------------------+
        |                                       |        m=           |
        |                                       +---------------------+
        |        +---------------------+        +---------------------+
        ====     | Stream Description  |  ===== |      a=rtpmap       |
        |        +---------------------+        +----------------------
        |                                       +---------------------+
        |                                       |      a=fmtp         |
        |                                       +---------------------+
        |                                       +---------------------+
        |                                       |      a=sendrecv..   |
        |                                       +---------------------+
+---------------+
|    SEMANTIC   |
| COMPONENTS OF |
|     SDP       |
+---------------+
        |                                       +---------------------+
        |                                       |      a=crypto       |
        |                                       +---------------------+
        |         +---------------------+       +---------------------+
        ====      |Security Descriptions|  =====|      a=ice-frag     |
        |         +---------------------+       +----------------------
        |                                       +---------------------+
        |                                       |      a=ice-pwd      |
        |                                       +---------------------+
        |                                       +---------------------+
        |                                       |     a=fingerprint   |
        |                                       +---------------------+
        |
        |
        |
        |                                       +---------------------+
        |                                       |      a=rtcp-fb      |
        |                                       +---------------------+
        |         +---------------------+       +---------------------+
        ====      |   Qos,Grouping      |       |                     |
                  |   Descriptions      |  =====|       a=group       |
                  +---------------------+       +----------------------
                                                +---------------------+
                                                |       a=rtcpmux     |
                                                +---------------------+




          ]]></artwork>
      </figure>
      <t><xref target="WebRTC"></xref> proposes JavaScript application to
      fully specify and control the signaling plane of a multimedia session as
      described in the JSEP specification <xref target="I-D.ietf-rtcweb-jsep"></xref>. JSEP
      provides mechanisms to create session characterization and media
      definition information to conduct the session based on SDP exchanges.</t>
      <t>In this context, SDP serves two purposes:
        <list style="numbers">
          <t>Provide grammatical structure syntactically.</t>
          <t>Semantically convey participant's intention and capabilities
           required to successfully negotiate a session.</t>
         </list>
      </t>
    </section>
    <section title="Offer/Answer and the WebRTC">
    <t>This section introduces SDP Offer/Answer Exchange mechanism mandated by
    WebRTC for negotiating session capabilities while setting up, updating and
    tearing down a WebRTC session. This section is intentionally brief in
    nature and interested readers are recommended to refer
    <xref target="RFC3264"></xref> for specific details on the protocol
    operation.</t>
    <t>The Offer/Answer <xref target="RFC3264"></xref> model specifies rule for
    the bilateral exchange of Session Description Protocol (SDP) messages for
    creation of multimedia streams. It defines protocol with involved
    participants exchanging desired session characteristics from each others
    perspective constructed as SDP to negotiate the session between them.</t>
    <t>In the most basic form,the protocol operation begins by one of the
    participants sending an initial SDP Offer describing its intent to start a
    multimedia communication session. The participant receiving the offer MAY
    generate an SDP Answer accepting the offer or it MAY reject the offer. If
    the session is accepted the Offer/Answer model guarantees a common view of
    the multimedia session between the participants.</t>
    <t>At any time, either participant MAY generate a new SDP offer that
    updates the session in progress.</t>
    <t>With in the context of WebRTC, the Offer/Answer model defines the
    state-machinery for WebRTC peers to negotiate session descriptions between
    them during the initial setup stages as well as for eventual session updates.
    Javascript Session Establishment Protocol specification
    <xref target="I-D.ietf-rtcweb-jsep"></xref> for WebRTC provides the mechanism for
    generating <xref target="RFC3264"></xref> SDP Offers and Answers in order
    for both sides of the session to agree upon details such as list of media
    formats to be sent/received, bandwidth information, crypto parameters,
    transport parameters, for example.</t>
    </section>

    <section title="WebRTC Session Description Examples">
     <t>A typical web based real-time multimedia communication session can be
     characterized as below:</t>
      <t>
      <list style="symbols">
        <t> It has zero or more Audio only, Video only or Audio/Video RTP
        Sessions,</t>
        <t> MAY contain zero or more non-media data sessions,</t>
        <t> All the sessions are secured with DTLS-SRTP,</t>
        <t> Supports NAT traversal using ICE mechanism,</t>
        <t> Provides RTCP based feedback mechanisms, </t>
        <t> Sessions can be over IPv4-only, IPv6-only, dual-stack based
        clients.</t>
       </list>
     </t>
      <section title="Some Conventions">
      <t>
      The examples given in this document follow the conventions listed
      below:
      </t>
      <t>
      <list style="symbols">
        <t>In all the examples, Alice and Bob are assumed to be the WebRTC
        peers.</t>
        <t><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"/> support for
        multiplexing several media streams over a single underlying transport is
        assumed by default unless explicitly specified otherwise.</t>
        <t>Call-flow diagrams that accompany the use-cases capture only the
        prominent aspects of the system behavior and intentionally is not
        detailed to improve readability.</t>
        <t>Eventhough the call-flow diagrams shows SDP being exchanged 
        between the parties, it doesn't represent the only way an 
        WebRTC setup is expected to work. Other approaches may involve WebRTC 
        applications to exchange the media setup information via non-SDP 
        mechanisms as long as they confirm to the 
        <xref target="I-D.ietf-rtcweb-jsep"></xref> API specification.</t>
        <t>The SDP examples deviate from actual on-the-wire SDP notation in
        several ways. This is done to facilitate readability and to conform to
        the restrictions imposed by the RFC formatting rules.
          <list style="symbols">
            <t>
             Any SDP line that is indented (compared to the initial line in the
             SDP block) is a continuation of the preceding line. The line
             break and indent are to be interpreted as a single space
             character.
             </t>
            <t>
              Empty lines in any SDP example are inserted to make functional
              divisions in the SDP clearer, and are not actually part of the
              SDP syntax.
            </t>
            <t>
             Excepting the above two conventions, line endings are to be
             interpreted as <CR><LF> pairs (that is, an ASCII 13 followed
             by an ASCII 10).
            </t>
           </list>
        </t>
        <t>Against each SDP line, pointers to the appropriate RFCs are provided
        for further informational reference. Also an attempt has been made to
        provide explanatory notes to enable better understanding of the SDP
        usage, wherever appropriate.</t>
        <t>Following SDP details are common across all the use-cases defined in
        this document unless mentioned otherwise.
         <list>
           <t> DTLS fingerprint for SRTP (a=fingerprint) </t>
           <t> RTP/RTCP Multiplexing (a=rtcp-mux) </t>
           <t> RTCP Feedback support (a=rtcp-fb) </t>
           <t> Host and server-reflexive candidate lines (a=candidate) </t>
           <t> SRTP Setup framework parameters (a=setup) </t>
           <t> RTCP attribute (a=rtcp) </t>
           <t> RTP header extension indicating audio-levels from client to the
           	mixer</t>
         </list>
        For more details, readers are recommended to refer to <xref target="I-D.ietf-rtcweb-jsep"></xref>
        specification.</t>
        <t>The term "Session" is used rather loosely in this document to refer to
        either a "Communication Session" or a "RTP Session" or a "RTP Stream"
        depending on the context.</t>
        <t>Payload type 109 is usually used for OPUS, 0 for PCMU, 8 for PCMA,
        99 for H.264 and 120 for VP8 in most of the examples to maintain
        uniformity.</t>
        <t>In the actual use the values that represent SSRCs, ICE candidate
        foundations, WebRTC Mediastream and MediaStreamTrack Ids shall be much
        larger and random than the ones shown in the examples.</t>
       </list>
       <list style="hanging">
        <t>[OPEN ISSUE-1]: SDP Examples for Data Channel, Simulcast, SVC are
        still being discussed and doesn't represent the final solution.</t>
       </list>
      </t>
      </section>
      <section title="Basic Examples">
      	<section anchor="sec.2way.audio" title="Audio Only Session">
        	<t>This common scenario shows SDP for secure two-way audio session
        	with Alice offering Opus, PCMU, PCMA and Bob accepting all the
        	offered audio codecs.</t>
        	<figure>
          <artwork alt="Successful-Session 2 Way Audio SAVPF"
              type="call-flow" align="left"><![CDATA[
        2-Way Audio Only Session

Alice                                Bob
|                                     |
|                                     |
|    Offer(Audio:Opus,PCMU,PCMA)      |
|------------------------------------>|
|                                     |
|                                     |
|   Answer(Audio:Opus,PCMU,PCMA)      |
|<------------------------------------|
|                                     |
|                                     |
|Two-way Opus Audio (preferred-codec) |
|.....................................|
|                                     |
|                                     |

]]></artwork>
        </figure>
        <texttable anchor="t_2way-audio_1" title="5.2.1 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 0 8</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Alice can perform RTP/RTCP Muxing </c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref>
          - Opus Codec 48khz, 2 channels</c>
          <c>a=ptime:60</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref>
          - Opus packetization of 60ms</c>
          <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref> PCMU Audio Codec</c>
          <c>a=rtpmap:8 PCMA/8000</c>
          <c><xref target="RFC3551"></xref> PCMA Audio Codec</c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref> Alice supports RTP header
          extension to indicate audio levels</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Alice can send and recv audio</c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> - ICE user fragment</c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref> - ICE password</c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> - RTP Host Candidate</c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> - RTCP Host Candidate</c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 64678 typ srflx 
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> - RTP Server Reflexive
          ICE Candidate</c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> - RTCP Server Reflexive
          Candidate</c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> - Indicates NACK RTCP feedback
          support</c>
          <c>a=ssrc:12345 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref> - Alice intends to use reduced
          size RTCP for this session</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        <texttable anchor="t_2way-audio_2" title="5.2.1 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109 0 8</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref> Opus Codec</c>
          <c>a=ptime:60</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref> Packetization
          of 60ms</c>
          <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref> PCMU Audio Codec</c>
          <c>a=rtpmap:8 PCMA/8000</c>
          <c><xref target="RFC3551"></xref> PCMA Audio Codec</c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref> Bob supports audio level RTP
          header extension as well</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Bob can send and recv audio</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Bob can perform RTP/RTCP Muxing
          on port 49203</c>
          <c>a=fingerprint:sha-1 c9:c7:70:9d:1f:66:79:a8:07:99:41:49:83:4a:
          97:0e:1f:ef:6d:f7</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=ice-ufrag:05067423</c>
          <c><xref target="RFC5245"></xref> - ICE user fragment</c>
          <c>a=ice-pwd:1747d1ee3474a28a397a4c3f3af08a068</c>
          <c><xref target="RFC5245"></xref> - ICE password parameter</c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> - RTP/RTCP Host ICE Candidate</c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 60654 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> - RTP/RTCP Server Reflexive ICE
          Candidate</c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> - Indicates NACK RTCP feedback
          support</c>
          <c>a=ssrc:54321 cname:NWs1ao1HmN4Xa5/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref> - Bob intends to use reduced
          size RTCP for this session</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
      	</section>
      	<section anchor="sec.2way.av"
        	title="Audio/Video Session">
        	<t>Alice and Bob establish a two-way audio and video session with
        	Opus as the audio codec and H.264 as the video codec.</t>
        	<figure>
           <artwork alt="Successful-Session 2 Way SAVPF">
<![CDATA[
         2-Way Audio,Video Session

Alice                                       Bob
|                                            |
|                                            |
|Offer(Audio:Opus,PCMU,PCMA Video:H.264,VP8) |
|------------------------------------------->|
|                                            |
|                                            |
|      Answer(Audio:Opus,Video:H.264)        |
|<-------------------------------------------|
|                                            |
|                                            |
|     Two-way Opus Audio, H.264 Video        |
|............................................|
|                                            |

]]></artwork>
        </figure>
        <texttable anchor="t_2way-av_1" title="5.2.2 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 0 8</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID
          (ta) </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Alice can perform RTP/RTCP Muxing
          </c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref>
          - Opus Codec 48khz, 2 channels</c>
          <c>a=ptime:60</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref>
          - Opus packetization of 60ms</c>
		      <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref> PCMU Audio Codec</c>
          <c>a=rtpmap:8 PCMA/8000</c>
          <c><xref target="RFC3551"></xref> PCMA Audio Codec</c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Alice can send and recv audio</c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> - ICE user fragment</c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref> - ICE password parameter</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> - RTP Host Candidate</c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> - RTCP Host Candidate </c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> - RTP Server Reflexive ICE Candidate</c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> - RTCP Server Reflexive Candidate.</c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> - Indicates NACK RTCP
          feedback support</c>
          <c>a=ssrc:12345 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref> - Alice intends to use reduced
          size RTCP for this session</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=video 54609 UDP/TLS/RTP/SAVPF 99 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID
          (tb) </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Alice can perform RTP/RTCP
          Muxing</c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtpmap:99 H264/90000</c>
          <c><xref target="RFC3984"></xref> - H.264 Video Codec</c>
          <c>a=fmtp:99 profile-level-id=4d0028;packetization-mode=1</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref> - VP8 video codec</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Alice can send and recv video</c>
		      <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> - ICE user fragment</c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref> - ICE password parameter</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> - RTP Host ICE Candidate</c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> - RTCP Host Candidate </c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> - RTP Server Reflexive ICE Candidate</c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> - RTCP Server Reflexive
          Candidate</c>
          <c>a=rtcp-fb:99 nack</c>
          <c><xref target="RFC5104"></xref> - Indicates NACK RTCP feedback
          support</c>
          <c>a=rtcp-fb:99 nack pli</c>
          <c><xref target="RFC5104"></xref> - Indicates support for Picture
          loss Indication and NACK</c>
          <c>a=rtcp-fb:99 ccm fir</c>
          <c><xref target="RFC5104"></xref> - Full Intra Frame Request-Codec
          Control Message support</c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> - Indicates NACK RTCP feedback
          support</c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> - Indicates support for Picture
          loss Indication and NACK</c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref> - Full Intra Frame Request-Codec
          Control Message support</c>
          <c>a=ssrc:1366781083 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref> - Alice intends to use
          reduced size RTCP for this session</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        <texttable anchor="t2way-av_2" title="5.2.2 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Bob can perform RTP/RTCP Muxing</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref> - Bob accepts
          only Opus Codec</c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:60</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Bob can send and recv audio</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake in
          parallel</c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> -  ICE username frag</c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> - ICE password</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP 3618095783 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> - RTP/RTCP Host ICE Candidate</c>
          <c>a=candidate:1 1 UDP 565689203 98.248.92.77 60065 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> - RTP/RTCP Server Reflexive ICE 
          Candidate</c>
          <c>a=ssrc:1366788312 cname:1f0fcgEocUG/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref> - Bob intends to use reduced
          size RTCP for this session</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 99</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID
          (tb) </c>
          <c>a=rtpmap:99 H264/90000</c>
          <c><xref target="RFC3984"></xref> - Bob accepts H.264 Video Codec.</c>
          <c>a=fmtp:99 profile-level-id=4d0028;packetization-mode=1</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Bob can perform RTP/RTCP 
          Muxing</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Bob can send and recv video</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> -  ICE username frag</c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> - ICE password</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> - Host ICE Candidate for
          Opus Stream</c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 60065 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> - Server Reflexive ICE Candidate
          for the above host candidate</c>
          <c><xref target="RFC5245"></xref> - Server Reflexive Candidate for
          the Second Host Candidate</c>
          <c>a=rtcp-fb:99 nack </c>
          <c><xref target="RFC5104"></xref> - Indicates support for NACK
          based RTCP feedback</c>
          <c>a=rtcp-fb:99 nack pli</c>
          <c><xref target="RFC5104"></xref> - Indicates support for
          Picture loss Indication and NACK</c>
          <c>a=rtcp-fb:99 ccm fir</c>
          <c><xref target="RFC5104"></xref> - Full Intra Frame Request-
          Codec Control Message support</c>
          <c>a=ssrc:3229706345 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref> - Bob intends to use reduced
          size RTCP for this session</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
      	</section>
      	<section
        	title="Data Only Session">
        	<t>This scenario illustrates SDP negotiated to setup a data-only
            session based on SCTP Data Channel, thus enabling use-cases such
            as file-transfer for example.</t>
        	<figure>
          <artwork alt="Successful-Data Only Session">
<![CDATA[
      2-Way DataChannel Session

Alice                            Bob
|                                 |
|                                 |
|                                 |
|      Offer(DataChannel)         |
|-------------------------------->|
|                                 |
|                                 |
|      Answer(DataChannel)        |
|<--------------------------------|
|                                 |
|                                 |
| Two-way SCTP based DataChannel  |
|.................................|
|                                 |
|                                 |

]]></artwork>
        </figure>
        <texttable anchor="t2way-dc_1" title="5.2.3 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=group:BUNDLE data</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> - Session Level ICE parameter</c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref> - Session Level ICE parameter</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - Session DTLS Fingerprint for
          SRTP</c>
          <c>m=application 56966 DTLS/SCTP 5000</c>
          <c><xref target="I-D.ietf-rtcweb-data-channel"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:data</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=sctpmap:5000 webrtc-DataChannel streams=16;label="channel 1";
          subprotocol="chat";</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Alice can send and recv non-media
          data</c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 56966 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 24.23.204.141 56966 typ srflx
          raddr 192.168.1.7 rport 56966</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        <texttable anchor="t_2way-dc_2" title="5.2.3 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=group:BUNDLE data</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=application 55700 DTLS/SCTP 5000</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref> </c>
          <c>c=IN IP4 98.248.92.771</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:data</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=sctpmap:5000 webrtc-DataChannel:5000 streams=1;label="channel 1"
          ;subprotocol="chat";</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Bob can send and recv
          non-media data</c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> - Session Level ICE username frag</c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> - Session Level ICE password</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - Session DTLS Fingerprint for
          SRTP</c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 55700 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 55700 typ srflx raddr
          192.168.1.7 rport 55700</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
      	</section>
      	<section anchor="audio_on_hold"
        	title="Audio Call On Hold">
        	<t>Alice calls Bob, but when Bob answers he places Alice on
            hold by setting the SDP direction attribute to a=sendonly in the
            Answer.</t>
        	<figure>
          <artwork alt="Audio On Hold">
<![CDATA[
           Audio On Hold

Alice                            Bob
|                                 |
|                                 |
|      Offer(Audio:Opus)          |
|-------------------------------->|
|                                 |
|                                 |
|  Answer(Audio:Opus,a=sendonly)  |
|<--------------------------------|
|                                 |
|                                 |
|      One-way Opus Audio         |
|.................................|
|                                 |
|
]]></artwork>
        </figure>
        <texttable anchor="t_audio_on_hold_1" title="5.2.4 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Alice can perform RTP/RTCP
          Muxing</c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref>
          - Opus Codec 48khz, 2 channels</c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref>
          - Opus packetization of 20ms</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Alice can send and recv audio</c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> -  ICE user fragment </c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref> -  ICE password</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> - Indicates NACK RTCP feedback
          support</c>
          <c>a=ssrc:3229706345 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        <texttable anchor="t_audio_on_hold_2" title="5.2.4 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref> - Bob accepts
          Opus Codec</c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref> - Bob puts call On Hold</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Bob can perform RTP/RTCP Muxing</c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> - ICE username frag</c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> - ICE password</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:1366781083 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
      	</section>
      	<section anchor="sec.audio.dtmf"
        	title="Audio with DTMF Session">
        	<t>In this example, Alice wishes to establish two separate
            audio streams, one for normal audio and the other for
            telephone-events. Alice offers first audio stream with three
            codecs and the other with <xref target="RFC2833"/> tones (for DTMF).
            Bob accepts both the audio streams by choosing Opus as the
            audio codec and telephone-event for the other stream.</t>
        	<figure>
            <artwork alt="Audio With DTMF">
<![CDATA[
            Audio Session with DTMF

Alice                                              Bob
|                                                   |
|                                                   |
|                                                   |
|  Offer(Audio:Opus,PCMU,PCMA Audio:telephone-event)|
|-------------------------------------------------->|
|                                                   |
|                                                   |
|    Answer(Audio:Opus, Audio:telephone-event)      |
|<--------------------------------------------------|
|                                                   |
|                                                   |
|   Opus audio stream and telephone-event stream    |
|...................................................|
|                                                   |
            ]]></artwork>
        </figure>
        <texttable anchor="t_audio_dtmf_1" title="5.2.5 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio dtmf</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 0 8</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Alice can perform RTP/RTCP
          Muxing</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref>
          - Opus Codec 48khz, 2 channels</c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref>
          - Opus packetization of 20ms</c>
          <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref> PCMU Audio Codec</c>
          <c>a=rtpmap:8 PCMA/8000</c>
          <c><xref target="RFC3551"></xref> PCMA Audio Codec</c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Alice can send and recv audio</c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> -  ICE user fragment</c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref> - ICE password parameter</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> - Indicates NACK RTCP feedback
          support</c>
          <c>a=ssrc:3229706345 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 126</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:dtmf</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtpmap:126 telephone-event/8000</c>
          <c><xref target="RFC2833"></xref></c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref> - Alice can send DTMF Events</c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> -  ICE user fragment</c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref> - ICE password parameter</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> - DTLS Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> - Indicates NACK RTCP feedback
          support</c>
          <c>a=ssrc:9032206345 cname:L/N9lk1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          </texttable>
          <texttable anchor="t_audio_dtmf_2" title="5.2.5 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio dtmf</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID
          (ta) </c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref> - Bob accepts
          Opus Codec</c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Bob can send and receive Opus
          audio</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake in
          parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Bob can perform RTP/RTCP Muxing
          on port 49203</c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> -  ICE username frag</c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> -  ICE password</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> -  Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ssrc:0634322975 cname:Q/o1HmN4XNWs1aa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref> - Alice intends to use reduced size
          RTCP for this session</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 126</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:dtmf</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack
          ID (tb) </c>
          <c>a=rtpmap:126 telephone-event/8000</c>
          <c><xref target="RFC2833"></xref></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref> - Alice can receive DTMF events</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Alice can perform RTP/RTCP Muxing
          on port 54690</c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> -  ICE username frag</c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> -  ICE password</c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> -  Fingerprint for SRTP</c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:6345903220 cname:L/k1aN9lo1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref> - Alice intends to use reduced
          size RTCP for this session</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
      	</section>
      	<section anchor="sec.av.oneway"
        	title="One Way Audio/Video Session - Document Camera">
        	<t>In this scenario Alice and Bob engage in a 1 way audio and video
        	session with Bob receiving Alice's audio and her presentation
        	slides as video stream.</t>
        <figure>
          <artwork alt="One Way Audio Video Session">
<![CDATA[

   One Way Audio & Video Session - Document Camera


Alice                                                 Bob
|                                                      |
|                                                      |
|                                                      |
|   Alice Offers sendonly audio and video streams.     |
|  The video stream corresponds to her presentation    |
|                                                      |
|           Offer(Audio:Opus, Video: VP8)              |
|----------------------------------------------------->|
|                                                      |
|                                                      |
|            (Audio:Opus, Video: VP8)                  |
|<-----------------------------------------------------|
|                                                      |
|                                                      |
|          One-way Opus Audio, VP8 Video               |
|......................................................|
|   Bob can hear Alice and see her presentation slides.|
|                                                      |
|                                                      |

]]></artwork>
        </figure>
        <texttable anchor="table_av_oneway_1" title="5.2.6 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref> - Send only audio stream</c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 24.23.204.141 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2122194687 24.23.204.141 54609 typ host</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:6345903220 cname:L/k1aN9lo1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=video 54609 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=content:slides</c>
          <c><xref target="RFC4796"></xref> -Alice's presentation video stream</c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref> - Send only video stream</c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 24.23.204.141 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 24.23.204.141 54609 typ host</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:3429951804 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        <texttable anchor="table_av_oneway_2" title="5.2.6 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref> - Receive only audio stream</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 98.248.92.77 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ssrc:9513429804 cname:Q/o1HmNWs1aN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=content:slides</c>
          <c><xref target="RFC4796"></xref></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref> - Receive Only Alice's
          presentation stream</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 98.248.92.77 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ssrc:1366781083 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
      	</section>
        <section anchor="sec.successful.2way.bundle"
        title="Audio, Video Session with BUNDLE Support Unknown">
        <t>In this example, since Alice is unsure of the Bob's support of
        the BUNDLE framework, following 3 step procedures are performed in
        order to negotiate and setup a BUNDLE Address for the session
         <list style="symbols">
           <t>An SDP Offer, in which the Alice assigns unique addresses to
           each "m=" line in the BUNDLE group, and requests the Answerer to
           select the Offerer's BUNDLE address. </t>
           <t>An SDP Answer, in which the Bob indicates its support for BUNDLE,
           and assigns its own BUNDLE address for the BUNDLED m= lines. </t>
           <t> A subsequent SDP Offer from Alice, which is used to perform
           BUNDLE Address Synchronization (BAS).</t>
         </list>
         Once the Offer/Answer exchange completes, both Alice and Bob
         each end up using single RTP Session for both the Media Streams.</t>
        <figure>
          <artwork alt="Successful-Session 2 Way BUNDLE">
<![CDATA[

 Two-Way Secure Audio,Video with BUNDLE support unknown

Alice                                                 Bob
|                                                      |
|                                                      |
|   Alice offers BUNDLE support with unique address    |
|        for the audio and video m-line                |
|                                                      |
|                                                      |
|          Offer(Audio:Opus Video:VP8)                 |
|----------------------------------------------------->|
|                                                      |Bob
|                                                      |supports
|                                                      |BUNDLE
|          Answer(Audio:Opus Video:VP8)                |
|<-----------------------------------------------------|
|                                                      |
|                                                      |Bob uses
|                                                      |identical
|                                                      |addresses
|                                                      |
|  Updated Offer for Bundle Address Synchronization.   |
|----------------------------------------------------->|
|                                                      |
|                                                      |
|       Answer (Bob accepts the updated offer)         |
|<-----------------------------------------------------|
|                                                      |
|                                                      |
|    2 Way Call with Audio and Video Multiplexed       |
|......................................................|
|                                                      |

]]></artwork>
        </figure>
        <texttable anchor="table_2waybundle_1" title="5.2.7 SDP Offer w/BUNDLE">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref> Audio m=line part of BUNDLE group
          with a unique port number</c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta)
          </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ssrc:11111 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=video 62537 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref> Video m=line part of the
          Bundle group with a unique port number</c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb)
          </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=rtcp:62537 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref> - Port for RTCP data</c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=ssrc:22222 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:6550074c</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:74af08a068a28a397a4c3f31747d1ee34</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 1f:ef:6d:f7:c9:c7:70:9d:1f:66:99:41:49:83:
          4a:97:0e79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 62537 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 2122194687 192.168.1.4 62537 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 62537 typ srflx
          raddr 192.168.1.4 rport 62537</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1685987071 24.23.204.141 62537 typ srflx
          raddr 192.168.1.4 rport 62537</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        <texttable anchor="table_2waybundle_2"
						title="5.2.7 SDP Answer w/BUNDLE">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Bob supports BUNDLE semantics.</c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta)
          </c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref> Audio m=line part of the
          BUNDLE group</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:33333 cname:Q/1HmN4Xa5NWs1ao</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref> Video m=line part of the
          BUNDLE group with the port from audio line repeated </c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb)
          </c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:44444 cname:Q/2AqlmN4Xa5NWs</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:85bc300d</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:bd2de4e9991c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 41:49:83:4a:99:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        <texttable anchor="table_2waybundle_3" title="5.2.7 SDP Offer for BAS">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref>  - Port number finalized as
          Bundle Address.</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=ssrc:11111 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
           <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=video 54609 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref > </c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:22222 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        </section>
<!-- COMMENTING THIS EXAMPLE since we made BUNDLE uniform across all the examples.
        <section anchor="sec.successful-2way-bundle-one-exchange"
        title="Audio, Video w/BUNDLE Support Known">
        <t>
         This use-case is a successful audio and video stream multiplexing scenario,
         with Alice and Bob aware of each others support for SDP BUNDLE framework
         <xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"/>.
         </t>
    <figure>
          <artwork alt="Successful-Session 2 Way BUNDLE Support Known"
            src="2waybundleknown.svg"><![CDATA[
title 2-Way Secure Audio, Video with BUNDLE support Known

Alice->Bob: Offer(Audio:Opus Video:VP8)
note right of Alice
Alice offers BUNDLE support with identical address across m-lines.
end note

Bob->Alice: Answer(Audio:Opus Video:VP8) indicating its support for BUNDLE
note left of Bob
Bob uses identical addresses across the m=lines
end note

Alice <-> Bob: 2Way Call with Audio and Video Multiplexed
]]></artwork>
        </figure>
        <texttable anchor="table_2waybundleknown_1" title="5.3.2 SDP Offer w/BUNDLE">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics.</c>
          <c>m=audio 10000 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref> - Audio m=line part of BUNDLE group</c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before Answer arrives</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:11111 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 10000 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 10000 typ srflx raddr 192.168.1.4 rport 10000</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 10000 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref> - Video m=line with Bundle address same as the audio m=line</c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before Answer arrives</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:22222 cname:Q/1HmN4Xa5NWs1ao</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 10000 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 10000 typ srflx raddr 192.168.1.4 rport 10000</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 24.23.204.141 64678 typ srflx raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_2waybundleknown_2" title="5.3.2 SDP Answer w/BUNDLE">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref> - Bob supports
          BUNDLE semantics.</c>
          <c>m=audio 20000 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref> - Audio m=line part of the BUNDLE group</c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake in parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:33333 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 20000 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 20000 typ srflx raddr 192.168.1.7 rport 20000</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 98.248.92.77 60065 typ srflx raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 20000 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref> - Video m=line with Bundle address
          same as the audio m=line </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake in parallel</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:44444 cname:1f0fcgEocUG/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 20000 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 20000 typ srflx raddr 192.168.1.7 rport 20000</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 98.248.92.77 60065 typ srflx raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      </section>
-->
      <section anchor="avd-2way"
        title="Audio, Video and Data Session">
        <t>This example shows SDP for negotiating a session with Audio,
        Video and data streams between Alice and Bob with BUNDLE support
        known.</t>
        <figure>
          <artwork alt="Successful-Session 2 Way SAVPF">
<![CDATA[

    Audio,Video,Data with BUNDLE support known

Alice                                       Bob
|                                            |
|                                            |
|Alice indicates BUNDLE support with         |
|identical address across all the m=lines    |
|                                            |
|                                            |
|     Offer(Audio:Opus Video:VP8 Data)       |
|------------------------------------------->|
|                                            |Bob does
|                                            |the same
|    Answer(Audio:Opus,Video:VP8 Data)       |
|<-------------------------------------------|
|                                            |
|                                            |
|                                            |
|    Two-way Audio,Video, Data multiplexed   |
|............................................|
|                                            |
|                                            |

]]></artwork>
        </figure>

    	 <texttable anchor="table_avd-2way_1" title="5.2.8 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video data</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref> </c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ssrc:11111 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=video 54609 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> </c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:22222 cname:Q/aoNWs11HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=application 54609 DTLS/SCTP 5000</c>
          <c><xref target="I-D.ietf-rtcweb-data-channel"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:data</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=sctpmap:5000 webrtc-DataChannel streams=1;label="channel 1";
          subprotocol="chat";</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
        </texttable>
        <texttable anchor="table_avd-2way_2" title="5.2.8 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video data</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref> </c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref>
          Bob's trickle support support is indicated at the session level</c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> </c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> </c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 49203 typ srflx
					raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:33333 cname:L/aoNWs11HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:44444 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=application 49203 DTLS/SCTP 5000</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref> </c>
          <c>c=IN IP4 98.248.92.771</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:data</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=sctpmap:5000 webrtc-DataChannel streams=16;label="channel 1";
          subprotocol="chat";</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
        </texttable>
   </section>
<!--
    <section anchor="sec.successful-session-remove-datachannel"
          title="Secure Two-way Audio,Video,Data and remove data stream">
        <t>
          This scenario builds upon from the usecase in the section 5.1.7
          It extends by Alice removing data-stream once the session is in progress.
        </t>
        <t hangText="Note">
          There is an ongoing discussion with in the working group to allow addition
          and deletion of streams using partial Offer/Answer exchanges based on
          m=lines. Once a final decision is reached, the following example shall be
          updated to reflect the same.
        </t>
        <figure>
          <artwork alt="Successful-Session Remove Data"
            src="avd-d.svg"><![CDATA[
title WebRTC Session (Audio,Video,Datachannel) - Drop Datachannel
note right of Alice
    Alice & Bob are in a two-way audio,video and datachannel session.
    Alice decides to stop the datachannel stream
end note
Alice->Bob: Offer(Audio:Opus Video:VP8, Application: Drop)
Bob->Alice: Answer(Audio:Opus Video:VP8, Application:Drop)
Alice->Bob: Two-way Opus Audio and VP8 Video
]]></artwork>
        </figure>
        <t>
          As a precondition, A Two-Way Audio,Video and Data Session is already setup.
        </t>
        <texttable anchor="table_avd-d_1" title="5.1.8 SDP Updated Offer w/DataChannel Drop">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=1</c>
          <c><xref target="RFC4566"></xref> Incremented version to indicate the update</c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 0 109 98</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtpmap:98 iLBC/8000
            a=fmtp:98 mode=20</c>
          <c><xref target="RFC3952"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>m=video  62537 UDP/TLS/RTP/SAVPF 99 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:99 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:99 profile-level-id=4d0028;packetization-mode=1</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 62537 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1694302207 24.23.204.141 62537 typ srflx raddr 192.168.1.4 rport 62537</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 2113667326 192.168.1.4 54721 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 24.23.204.141 54721 typ srflx raddr 192.168.1.4 rport 54721</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:99 nack pli</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:99 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>m=application 0 DTLS/SCTP 5000</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref> - Port 0 indicates dropping data stream </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=sctmap:5000 webrtc-DataChannel 1</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=webrtc-DataChannel:5000 stream=1;label="channel 1";subprotocol="chat";</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
        </texttable>
        <texttable anchor="table_avd-d_2" title="5.1.8 SDP Updated Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=1</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 49203 typ srflx raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 98.248.92.77 60065 typ srflx raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>m=video  63130 UDP/TLS/RTP/SAVPF 99</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>c=IN IP4 98.248.92.771</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:99 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:99 profile-level-id=4d0028;packetization-mode=1</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 63130 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 63130 typ srflx raddr 192.168.1.7 rport 63130</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 56607 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 98.248.92.77 56607 typ srflx raddr 192.168.1.7 rport 56607</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:99 nack pli</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:99 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>m=application  0 DTLS/SCTP 5000</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref> Bob accepts dropping the data stream </c>
          <c>c=IN IP4 98.248.92.771</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=sctpmap:5000 webrtc-DataChannel 1</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=webrtc-DataChannel:5000 stream=1;label="channel 1";subprotocol="chat";</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
        </texttable>
      </section>
-->
      	<section anchor="successful-2way-bundle-unsupported"
        title="Audio, Video Session with BUNDLE Unsupported">
        <t>This use-case illustrates SDP Offer/Answer exchange where the
        far-end (Bob) either doesn't support media bundling or doesn't want
        to group m=lines over a single 5-tuple.</t>
        <t> On successful Offer/Answer exchange, Alice and Bob each end up
        using unique 5-tuple for audio and video media streams respectively.</t>
        <figure>
          <artwork alt="Successful-Session 2 Way BUNDLE Unsupported">
<![CDATA[

   Two-Way Secure Audio,Video with BUNDLE Unsupported

Alice                                                 Bob
|                                                      |
|                                                      |
|     Alice offers BUNDLE support with unique address  |
|           for the audio and video m-line             |
|                                                      |
|                                                      |
|           Offer(Audio:Opus Video:VP8)                |
|----------------------------------------------------->|
|                                                      |Bob
|                                                      |doesn't
|                                                      |support
|                                                      |BUNDLE
|           Answer(Audio:Opus Video:VP8)               |
|<-----------------------------------------------------|
|                                                      |Bob uses
|                                                      |unique
|                                                      |addresses
|                                                      |across the
|                                                      |m=lines
|                                                      |
|2Way Call with Audio and Video on different 5-tuples  |
|......................................................|
|                                                      |
|                                                      |

]]></artwork>
        </figure>
        <texttable anchor="table_2waybundlerej_1"
        	title="5.2.9 SDP Offer w/BUNDLE">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 55232 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref> Audio m=line part of BUNDLE group
          with a unique port number</c>
          <c>a=rtcp:55232 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ssrc:11111 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 55232 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.4 55232 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 55232 typ srflx
          raddr 192.168.1.4 rport 55232</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1685987071 24.23.204.141 55232 typ srflx
          raddr 192.168.1.4 rport 55232</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 54332 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref> Video m=line part of the
          BUNDLE group with a unique port number</c>
          <c>a=rtcp:54332 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> - Alice can perform DTLS before
          Answer arrives</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:22222 cname:yvY7/EocUG1f0fcg</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:7872093</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:ee3474af08a068a28a397a4c3f31747d1</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 6d:f7:c9:c7:70:9d:1f:66:79:a8:07:99:41:
          49:83:4a:97:0e:1f:ef</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2122194687 192.168.1.4 54332 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 2122194687 192.168.1.4 54332 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1685987071 24.23.204.141 54332 typ srflx
          raddr 192.168.1.4 rport 54332</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1685987071 24.23.204.141 54332 typ srflx
          raddr 192.168.1.4 rport 54332</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_2waybundlerej_2"
        	title="5.2.9 SDP Answer without BUNDLE">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 53214 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 53214 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 53214 typ srflx
          raddr 192.168.1.7 rport 53214</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2122194687 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1685987071 98.248.92.77 60065 typ srflx
          raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 58679 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:56507 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> - Bob carries out DTLS Handshake
          in parallel</c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> </c>
          <c>a=ice-ufrag:85bC300</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:325921d5d47efbabd9a2de4e99bd291c</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 9d:1f:66:79:a8:07:99:41:49:83:4a:97:0e:1f:
          ef:6d:f7:c9:c7:70</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 58679 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 58679 typ srflx
          raddr 192.168.1.7 rport 58679</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2122194687 192.168.1.7 56507 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1685987071 98.248.92.77 56507 typ srflx
          raddr 192.168.1.7 rport 58679</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      </section>
       <section anchor="av-d-not-bundle"
        title="Audio, Video BUNDLED, but Data (Not BUNDLED)">
        <t>This example show-cases SDP for negotiating a session with Audio, Video
        and data streams between Alice and Bob with data stream not being part of
        the BUNDLE group. This is shown by assigning unique port for data media
        sections.
        </t>
        <figure>
          <artwork alt="Successful-Session 2 Way SAVPF">
<![CDATA[
       Audio, Video, with Data (Not in BUNDLE)

Alice                                                 Bob
|                                                      |
|                                                      |
|Alice wants to multiplex audio, video but not data    |
|                                                      |
|                                                      |
|  Offer(Audio:Opus Video:VP8, Data(not in BUNDLE))    |
|----------------------------------------------------->|
|                                                      |
|                                                      |
|       Answer(Audio:Opus Video:VP8, Data)             |
|<-----------------------------------------------------|
|                                                      |
|                                                      |
|2 Way Call with Audio, Video Multiplexed except data  |
|......................................................|
|                                                      |


]]></artwork>
        </figure>
         <texttable anchor="table_av-nob-d-2way_1" title="5.2.10 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice wants to BUNDLE only audio and video media.</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ssrc:11111 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 54609 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:54609 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> </c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:22222 cname:Q/aoNWs11HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=application 10000 DTLS/SCTP 5000</c>
          <c><xref target="I-D.ietf-rtcweb-data-channel"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:data</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=sctpmap:5000 webrtc-DataChannel streams=16;label="channel 1";
          subprotocol="chat";</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=ice-ufrag:89819013</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:1747d1ee3474af08a068a28a397a4c3f3</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 0e:1f:ef:6d:f7:c9:c7:70:99:41:49:83:4a:97:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 10000 typ host</c>
          <c><xref target="RFC5245"></xref></c>
         </texttable>
        <texttable anchor="table_av-nob-d-2way_2" title="5.2.10 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref> </c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> </c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> </c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:
          70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:33333 cname:L/aoNWs11HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 98.248.92.771</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:44444 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=application 20000 DTLS/SCTP 5000</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref> </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:data</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=sctpmap:5000 webrtc-DataChannel streams=1;label="channel 1";
          subprotocol="chat";</c>
          <c><xref target="I-D.ietf-mmusic-sctp-sdp"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=ice-ufrag:991Ca2a5e</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:921d5d47efbabd9a2de4e99bd291c325</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=fingerprint:sha-1 6d:f7:c9:c7:70:9d:1f:66:79:a8:07:99:41:49:
          83:4a:97:0e:1f:ef</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 20000 typ host</c>
          <c><xref target="RFC5245"></xref></c>
        </texttable>
   </section>
   <section anchor="a-video-add"
        title="Audio Only, Add Video to BUNDLE">
        <t>This example involves 2 Offer/Answer exchanges. First one setting up
        Audio-only session followed by an updated Offer/Answer exchange to add
        video stream to the ongoing session. Also the newly added video stream
        is BUNDLED with the audio stream.</t>
        <figure>
          <artwork alt="AudioOnly-AddVideo">
<![CDATA[

         Audio Only , Add Video and BUNDLE

Alice                                                 Bob
|                                                      |
|                                                      |
|        Alice indicates support for BUNDLE            |
|                                                      |
|                Offer(Audio:Opus)                     |
|----------------------------------------------------->|
|                                                      |Bob
|                                                      |supports
|                                                      |BUNDLE
|                Answer(Audio:Opus)                    |
|<-----------------------------------------------------|
|                                                      |Alice adds
|                                                      |video stream
|        Updated Offer(Audio:Opus, Video:VP8)          |to BUNDLE
|----------------------------------------------------->|
|                                                      |
|                                                      |Bob accepts
|        Updated Answer(Audio:Opus, Video:VP8)         |
|<-----------------------------------------------------|
|                                                      |
|   2Way Call with Audio and Video Multiplexed         |
|......................................................|
|                                                      |
|                                                      |

]]></artwork>
        </figure>
          <texttable anchor="table_a_only_1" title="5.2.11 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice wants to BUNDLE only audio and video media.</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ssrc:11111 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_a_only_2" title="5.2.10 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref> </c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> </c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> </c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:
          70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:33333 cname:L/aoNWs11HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_a_only_3" title="5.2.11 SDP Updated Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=1</c>
          <c><xref target="RFC4566"> Version number incremented</xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice wants to BUNDLE only audio and video media.</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ssrc:11111 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 54609 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> </c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:22222 cname:Q/aoNWs11HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_a_only_4" title="5.2.11 SDP Updated Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=1</c>
          <c><xref target="RFC4566"></xref> Version number incremented</c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio video</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref> </c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> </c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> </c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:33333 cname:L/aoNWs11HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:video</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:44444 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
   </section>
     </section>
     <section title="MultiResolution, RTX, FEC Examples">
     <t>This section deals with scenarios related to multi-source,
     multi-stream negotiation such as layered coding, simulcast, along
     with techniques that deal with providing robustness against transmission
     errors such as FEC and RTX. Also to note, mechanisms such as FEC and RTX
     could be envisioned in the above basic scenarios as well.</t>
      	 <section anchor="sec.successful-session-simulcast"
        title="Sendonly Simulcast Session with 2 cameras and 2 encodings
				per camera">
        <t>The SDP below shows Offer/Answer exchange with one audio and two
        video sources. Each of the video source can be sent at two different
        resolutions.</t>
        <t>One video source corresponds to VP8 encoding, while the other
        corresponds to H.264 encoding. </t>
        <t>bundle-only framework is used along with BUNDLE grouping framework
        to enable multiplexing of all the 5 streams
        (1 audio stream + 4 video streams) over a single RTP Session.</t>
        <figure>
          <artwork alt="Successful-Session Simulcast">
<![CDATA[
       1 Way Successful Simulcast w/BUNDLE

Alice                                            Bob
|                                                 |
|                                                 |
|     Alice offers 2 sendonly video sources       |
|     with 2 simulcast encodings per source       |
|           and bundle-only for video             |
|                                                 |
|                                                 |
|   Offer(Audio:Opus,Video1:VP8,Video2:H.264)     |
|------------------------------------------------>|
|                                                 |
|                                                 |
|    Answer(Audio:Opus Video1:VP8,Video2:H.264)   |
|<------------------------------------------------|
|                                                 |
|One-Way 1 Opus, 2 H.264 and 2 VP8 video streams, |
| all multiplexed                                 |
|.................................................|
|                                                 |
|                                                 |


]]></artwork>
        </figure>
        <texttable anchor="table_1waysimulcast_1" title="5.3.1 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 m2</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ssrc:11111 C90alEocUG1f0fcg</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 98 100</c>
          <c>bundle-only video line with port number set to zero</c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:100 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=imageattr:98 [x=1280,y=720]</c>
          <c><xref target="RFC6236"></xref>Camera-1,Encoding-1 Resolution</c>
          <c>a=fmtp:98 max-fr=30</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=imageattr:100 [x=640,y=480]</c>
          <c><xref target="RFC6236"></xref> Camera-1,Encoding-2 Resolution</c>
          <c>a=fmtp:100 max-fr=15</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=simulcast: send 98;100</c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"></xref>
          Alice can send 2 resolutions</c>
          <c>a=ssrc:12345 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref>
          <xref target="RFC7022"></xref>
          Camera-1,Encoding-1 SSRC with Session CNAME</c>
          <c>a=ssrc:45678 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref>
          <xref target="RFC7022"></xref>
           Camera-1,Encoding-2 SSRC with Session CNAME</c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref> - Send only video stream</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-fb:98 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:98 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:98 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:100 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:100 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:100 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 101 102</c>
          <c> bundle-only video line with port number set to zero  </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tc </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tc) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m2</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=rtpmap:101 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=rtpmap:102 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:101 profile-level-id=4d0028;packetization-mode=1;max-fr=30 </c>
          <c><xref target="RFC3984"></xref>Camera-2,Encoding-1 Resolution</c>
          <c>a=fmtp:102 profile-level-id=4d0028;packetization-mode=1;max-fr=15</c>
          <c><xref target="RFC3984"></xref>Camera-2,Encoding-2 Resolution</c>
          <c>a=simulcast: send 101;102</c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"></xref></c>
          <c>a=ssrc:67890 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref>
          <xref target="RFC7022"></xref>
          Camera-2,Encoding-1 SSRC with Session CNAME</c>
          <c>a=ssrc:56789 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref>
          <xref target="RFC7022"></xref>
           Camera-2,Encoding-2 SSRC with Session CNAME</c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref> - Send only video stream</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-fb:101 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:101 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:101  ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:102 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:102 nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:102 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_1waysimulcast_2" title="5.3.1 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 m2</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:22222 cname:y8/C90alEocUG1f0fcg</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP  2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  694302207 98.248.92.77 49203 typ srflx
          raddr 192.168.1.4 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 98 100</c>
          <c>BUNDLE accepted with port repeated from the audio port </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:100 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=imageattr:98 [x=1280,y=720]</c>
          <c><xref target="RFC6236"></xref>Camera-1,Encoding-1 Resolution</c>
          <c>a=fmtp:98 max-fr=30</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=imageattr:100 [x=640,y=480]</c>
          <c><xref target="RFC6236"></xref> Camera-1,Encoding-2 Resolution</c>
          <c>a=fmtp:100 max-fr=15</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref> - receive only video stream</c>
          <c>a=simulcast: recv 98;100</c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"></xref></c>
          <c>a=ssrc:54321 cname:y8/C90alEocUG1f0fcg</c>
          <c><xref target="RFC5576"/> </c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 60065 typ srflx
          raddr 192.168.1.4 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
           <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux </c>
          <c><xref target="RFC5576"/> </c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 54609 UDP/TLS/RTP/SAVPF 101 102</c>
          <c> BUNDLE accepted with port repeated from the audio port </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtcp:56503 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=msid:ma tc </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tc) </c>
          <c>a=mid:m2</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=rtpmap:101 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=rtpmap:102 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=fmtp:101 profile-level-id=4d0028;packetization-mode=1;max-fr=30 </c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:102 profile-level-id=4d0028;packetization-mode=1;max-fr=15</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=simulcast: recv 101;102</c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"></xref>
          Bob accepts to receieve the offered simulcast streams</c>
          <c>a=ssrc:90876 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 60065 typ srflx
          raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux </c>
          <c><xref target="RFC5576"/></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      </section>
      	<section anchor="sec.successful-session-svc"
        title="Successful SVC Video Session">
        <t>This section shows an SDP Offer/Answer for a session with an audio
        and a single video source.  The video source is encoded as
        layered coding at 3 different resolutions based on
        <xref target="RFC5583"/>. The video m=line shows 3 streams with
        last stream (payload 100) dependent on streams with payload 96
        and 97 for decoding.</t>
        <figure>
          <artwork alt="Successful-Session SVC">
<![CDATA[
        SVC Session - 3 Layers w/BUNDLE

Alice                                            Bob
|                                                 |
|                                                 |
|      Alice offers 3 sendonly video streams      |
|      as 3 layers of SVC and bundle-only         |
|               for video streams.                |
|                                                 |
|            Offer(Video:H.264 SVC)               |
|------------------------------------------------>|
|                                                 |
|                                                 |Bob accepts Alice's
|                                                 |offered Codec
|                                                 |operation points
|                                                 |
|             Answer(Video:H.264)                 |
|<------------------------------------------------|
|                                                 |
|One-Way  H.264 SVC video streams                 |
|.................................................|
|                                                 |
|                                                 |


]]></artwork>
        </figure>
        <texttable anchor="table_svc_1" title="5.3.2 SDP Offer with SVC">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref> Audio m=line part of BUNDLE group
            with a unique port number</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ssrc:67890 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"/></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 96 97 100</c>
          <c>bundle-only video line with port number set to zero</c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tc) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref> Audio m=line part of BUNDLE group</c>
          <c>a=msid:ma tb</c>
          <c></c>
          <c>a=rtpmap:96 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:96 profile-level-id=4d0028;
          packetization-mode=1;max-fr=30;max-fs=8040</c>
          <c><xref target="RFC3984"></xref>H.264 Layer 1</c>
          <c>a=rtpmap:97 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:97 profile-level-id=4d0028;packetization-mode=1;
          max-fr=15;max-fs=1200</c>
          <c><xref target="RFC3984"></xref> H.264 Layer 2</c>
          <c>a=rtpmap:100 H264-SVC/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:100 profile-level-id=4d0028;packetization-mode=1;
          max-fr=30;max-fs=8040</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=depend:100 lay m1:96,97;</c>
          <c><xref target="RFC5583"></xref>Layer 3 dependent on layers 1 and 2</c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref> - Send only video stream</c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=ssrc:1732846380 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ssrc:1732846381 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ssrc:1732846382 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_svc_2" title="5.3.2 SDP Answer with SVC">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 60065 typ srflx
          raddr 192.168.1.5 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 54609 UDP/TLS/RTP/SAVPF 96 100</c>
          <c> BUNDLE accepted Bundle address same as audio m=line.</c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:56503 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=rtpmap:96 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:96 profile-level-id=4d0028;packetization-mode=1;
          max-fr=30;max-fs=8040</c>
          <c><xref target="RFC3984"></xref>H.264 Layer 1</c>
          <c>a=rtpmap:100 H264-SVC/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:100 profile-level-id=4d0028;packetization-mode=1;
          max-fr=30;max-fs=8040</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=depend:100 lay m1:96;</c>
          <c><xref target="RFC5583"></xref> Bob chooses 2 Codec Operation points</c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.5 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.142 64678 typ srflx
          raddr 192.168.1.5 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref> - Receive only video stream</c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=ssrc:4638117328 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      </section>
      	<section anchor="sec.successful-simulcast-rtx"
        title="Successful Simulcast Video Session with Retransmission">
        <t>This section shows an SDP Offer/Answer exchange for a
        simulcast scenario with 2 two resolutions and has
        <xref target="RFC4588"></xref> style re-transmission flows.</t>
        <figure>
          <artwork alt="Successful-Session Simulcast RTX">
<![CDATA[

      Simulcast Streams with Retransmission

Alice                                                    Bob
|                                                         |
|                                                         |
|Alice offers single audio and simulcasted video streams  |
|                                                         |
|                                                         |
|    Offer(Audio:Opus Video:VP8 with 2 resolutions)       |
|    & RTX stream                                         |
|-------------------------------------------------------->|
|                                                         |
|                                                         |
|          Answer (Bob accepts Alice's offer)             |
|<--------------------------------------------------------|
|                                                         |
|                                                         |
|One-Way 1 Opus, 2 VP8 and RTX video streams,all muxed    |
|.........................................................|
|                                                         |
|                                                         |

]]></artwork>
        </figure>
        <texttable anchor="table_simulcastrtx_1"
        	title="5.3.3 SDP Offer w/Simulcast, RTX">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref> Audio m=line part of BUNDLE group
           with a unique port number</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:11111 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:
          70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 98 100 101 103</c>
          <c>bundle-only video line with port number set to zero</c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:100 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:101 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:103 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=fmtp:98 max-fr=30;max-fs=8040</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:100 max-fr=15;max-fs=1200</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:101 apt=98;rtx-time=3000</c>
          <c><xref target="RFC4588"></xref></c>
          <c>a=fmtp:103 apt=100;rtx-time=3000</c>
          <c><xref target="RFC4588"></xref></c>
          <c>a=simulast: send 98;100 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"></xref></c>
          <c>a=ssrc-group:FID 12345 34567 </c>
          <c><xref target="RFC5888"/> </c>
          <c>a=ssrc-group:FID 78990 90887 </c>
          <c><xref target="RFC5888"/></c>
          <c>a=ssrc:12345 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ssrc:78990 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ssrc:34567 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ssrc:90887 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"/></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"/></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_simulcastrtx_2"
        	title="5.3.3 SDP Answer w/Simulcast, RTX">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:33333 cname:L/HmN4Xa5NWs1ao1</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 64678 typ
          srflx raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 98 100 101 103</c>
          <c>BUNDLE accepted with Bundle address identical to audio m-line</c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:100 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:101 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:103 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=fmtp:98 max-fr=30;max-fs=8040</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:100 max-fr=15;max-fs=1200</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:101 apt=98;rtx-time=3000</c>
          <c><xref target="RFC4588"></xref></c>
          <c>a=fmtp:103 apt=100;rtx-time=3000</c>
          <c><xref target="RFC4588"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:
          70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.772 60065 typ srflx
          raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=simulcast: recv 98;100 </c>
          <c> <xref target="I-D.ietf-mmusic-sdp-simulcast"/> </c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      </section>
      <section anchor="sec.successful-simulcast-rtxreject"
        title="Successful 1-way Simulcast Session with 2 resolutions and
        RTX - One resolution rejected">
        <t>This section shows an SDP Offer/Answer exchange for a simulcast
        scenario with 2 two resolutions.</t>
        <t>It also showcases when Bob rejects one of the Simulcast Video
        Stream which results in the rejection of the associated repair
        stream implicitly.</t>
        <figure>
          <artwork alt="Successful-Session Simulcast RTX">
<![CDATA[

     Simulcast Streams with Retransmission Rejected

Alice                                                    Bob
|                                                         |
|                                                         |
|Alice offers single audio and simulcasted video streams  |
| with bundle-only for video                              |
|                                                         |
|                                                         |
|Offer(Audio:Opus Video:VP8 with 2 resolutions,RTX Stream)|
|-------------------------------------------------------->|
|                                                         |
|                                                         |Bob accepts 1
|                                                         |simulcast,rtx
|                                                         |rejects the
|                                                         |other
|   Answer(Audio:Opus Video:VP8 with 1 res & RTX Stream)  |
|<--------------------------------------------------------|
|                                                         |
|                                                         |
|1-way audio,video session and its associated RTX stream, |
| all multiplexed                                         |
|.........................................................|
|                                                         |
|                                                         |


]]></artwork>
        </figure>
        <texttable anchor="table_simulcastrtxreg_1"
        	title="5.3.4 SDP Offer w/Simulcast, RTX">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:11111 cname:LP/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 98 100 101 103</c>
          <c>bundle-only video line with port number set to zero</c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:100 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:101 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:103 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=fmtp:98 max-fr=30;max-fs=8040</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:100 max-fr=15;max-fs=1200</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:101 apt=98;rtx-time=3000</c>
          <c><xref target="RFC4588"></xref></c>
          <c>a=fmtp:103 apt=100;rtx-time=3000</c>
          <c><xref target="RFC4588"></xref></c>
          <c>a=simulcast: send 98;100 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"/></c>
          <c>a=ssrc-group:FID 12345 34567 </c>
          <c><xref target="RFC5888"/> </c>
          <c>a=ssrc-group:FID 78990 90887 </c>
          <c><xref target="RFC5888"/></c>
          <c>a=ssrc:12345 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ssrc:78990 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ssrc:34567 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ssrc:90887 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_simulcastrtxreg_2"
        	title="5.3.4 SDP Answer no Simulcast">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:49203 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 60065 typ srflx
          raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 98 101 </c>
          <c>BUNDLE accepted with Bundle address identical to audio m-line</c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:101 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=fmtp:98 max-fr=30;max-fs=8040</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:101 apt=98;rtx-time=3000</c>
          <c><xref target="RFC4588"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 60065 typ srflx
          raddr 192.168.1.5 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=simulcast: recv 98 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"/>
          Bob accepts only one simulcast resolution</c>
          <c>a=ssrc:54321 cname:NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      </section>
      <section anchor="sec.successful-simulcast-fec"
        title="Simulcast Video Session with Forward Error Correction">
        <t>This section shows an SDP Offer/Answer exchange for Simulcast
        video stream at two resolutions and and has
        <xref target="RFC5956"></xref> style FEC flows.</t>
         <t> On completion of the Offer/Answer exchange mechanism we end up
         one audio stream, 2 simulcast video streams and 2 associated
         FEC streams are sent over a single 5-tuple.</t>
        <figure>
          <artwork alt="Successful-Session Simulcast FEC">
<![CDATA[
      Simulcast Streams with Forward Error Correction

Alice                                                            Bob
|                                                               |
|                                                               |
|                                                               |
|Alice offers single audio and simulcasted video streams        |
|with bundle-only                                               |
|                                                               |
|                                                               |
|Offer(Audio:Opus Video:VP8 with 2 resolutions with FEC Streams)|
|-------------------------------------------------------------->|
|                                                               |
|                                                               |Bob
|                                                               |accepts
|                                                               |Alice's
|                                                               |offer
|Answer(Audio:Opus Video:VP8 with 2 resolutions w/FEC Streams)  |
|<--------------------------------------------------------------|
|                                                               |
|One-Way Audio,Video session with 4 video streams(Simulcast     |
| and FEC) all multiplexed                                      |
|...............................................................|
|                                                               |
|                                                               |
|                                                               |

]]></artwork>
        </figure>
        <texttable anchor="table_12_1" title="5.3.5 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:11111 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ
          srflx raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 98 100 101 103</c>
          <c>bundle-only video line with port number set to zero</c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:100 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:101 1d-interleaved-parityfec/90000</c>
          <c><xref target="RFC5956"></xref></c>
          <c>a=rtpmap:103 1d-interleaved-parityfec/90000</c>
          <c><xref target="RFC5956"></xref></c>
          <c>a=fmtp:98 max-fr=30;max-fs=8040</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:100 max-fr=15;max-fs=1200</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:101 L=5; D=10; repair-window=200000</c>
          <c><xref target="RFC5956"></xref></c>
          <c>a=fmtp:103 L=5; D=10; repair-window=200000</c>
          <c><xref target="RFC5956"></xref></c>
          <c>a=simulcast: send 98;100 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"/></c>
          <c>a=depend:98 fec m1:101</c>
		  <c>TBD</c>
          <c>a=depend:100 fec m1:103</c>
          <c>TBD</c>
          <c>a=ssrc-group:FEC-FR 12345 34567 </c>
          <c><xref target="RFC5888"/> </c>
          <c>a=ssrc-group:FEC-FR 78990 90887 </c>
          <c><xref target="RFC5888"/></c>
          <c>a=ssrc:12345 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ssrc:78990 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ssrc:34567 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=ssrc:90887 cname:Q/NWs1ao1HmN4Xa5</c>
          <c><xref target="RFC5576"/></c>
          <c>a=sendonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="table_12_2" title="5.3.5 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS m0</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"/></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109 </c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref> Audio m=line part of BUNDLE group
          with a unique port number</c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=recvonly </c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ssrc:33333 cname:Y9/cZke09JAtpl98</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:
          1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 60065 typ srflx
          raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 49203 UDP/TLS/RTP/SAVPF 98 100 101 103</c>
          <c>BUNDLE accepted with Bundle Address identical to audio m=line.</c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid:ma tb </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:100 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:101 1d-interleaved-parityfec/90000</c>
          <c><xref target="RFC5956"></xref></c>
          <c>a=rtpmap:103 1d-interleaved-parityfec/90000</c>
          <c><xref target="RFC5956"></xref></c>
          <c>a=fmtp:98 max-fr=30;max-fs=8040</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:100 max-fr=15;max-fs=1200</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fmtp:101 L=5; D=10; repair-window=200000</c>
          <c><xref target="RFC5956"></xref></c>
          <c>a=fmtp:103 L=5; D=10; repair-window=200000</c>
          <c><xref target="RFC5956"></xref></c>
          <c>a=simulcast: recv 98;100 </c>
          <c><xref target="I-D.ietf-mmusic-sdp-simulcast"/></c>
          <c>a=depend:98 fec m1:101</c>
		  <c>TBD</c>
          <c>a=depend:100 fec m1:103</c>
          <c>TBD</c>
          <c>a=recvonly</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 60065 typ srflx
          raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* nack pli</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=rtcp-fb:* ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      </section>
      </section>
      <section title="Others">
        <t>
         The examples in the section provide SDP for a variety of scenarios
         related to RTP Header extension, Legacy Interop scenarios and more.
        </t>
      	<section anchor="sec.av.rtp_ext_vad"
        	title="Audio Session - Voice Activity Detection">
        	<t>This example shows Alice indicating the support of the
        	RTP header extension to include the audio-level of the audio
        	sample carried in the RTP packet.</t>
        	<figure>
          <artwork alt="Session 2 Way Audio with VAD"><![CDATA[
           2-Way Audio with VAD

 Alice                                    Bob
 |                                         |
 |                                         |
 |Alice indicates support for including    |
 |audio level in RTP header                |
 |                                         |
 |     Offer(Audio:Opus,PCMU,PCMA)         |
 |---------------------------------------->|
 |                                         |
 |                                         |
 |     Answer(Audio:Opus,PCMU,PCMA)        |
 |<----------------------------------------|
 |                                         |
 |                                         |Bob accepts and
 |                                         |indicates his
 |                                         |support as well
 |                                         |
 |     Two way Opus Audio                  |
 |.........................................|
 |                                         |
 |Per packet audio-level is included in the|
 |RTP header                               |
 |                                         |


]]></artwork>
        </figure>
        <texttable anchor="t_2way-audio-vad_1" title="5.4.1 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 0 8</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref></c>
          <c>a=rtpmap:0 PCMA/8000</c>
          <c><xref target="RFC3551"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:
          70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=ssrc:11111 cname:QCL/1HmN4Xa5CClapa</c>
          <c><xref target="RFC5576"/></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="t_2way-audio-vad_2" title="5.4.1 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109 0 98</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref> - Bob accepts
          only Opus Codec</c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref> PCMU Audio Codec</c>
          <c>a=rtpmap:0 PCMA/8000</c>
          <c><xref target="RFC3551"></xref> PCMA Audio Codec</c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Bob can send and recv audio</c>
          <c>a=setup:active</c>
		      <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> - Bob can perform RTP/RTCP Muxing on port 49203</c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:1732846380 cname:EocUG1f0fcg/yvY7</c>
          <c><xref target="RFC5576"/></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      	</section>
      	<section anchor="sec.aconf.rtp_ext_vad"
        	title="Audio Conference - Voice Activity Detection">
        	<t>This example shows SDP for RTP header extension that
        	allows RTP-level mixers in audio conferences to deliver information
        	about the audio level of individual participants.</t>
        	<figure>
          <artwork alt="Session 2 Way Audio with VAD">
<![CDATA[

     Audio Conference with VAD Support

Alice                                    Mixer
|                                         |
|Alice indicates her interest to audio    |
|levels for the contributing sources      |
|                                         |
|Offer(Audio:Opus,PCMU,PCMA)              |
|---------------------------------------->|
|                                         |
|                                         |
|Answer(Audio:Opus,PCMU,PCMA)             |
|<----------------------------------------|
|                                         |
|                                         |Mixer indicates
|                                         |it can provide
|                                         |audio-levels
|Two way Opus Audio                       |
|.........................................|
|                                         |
|Audio-levels per CSRCS is included in the|
|RTP header                               |
|                                         |


]]></artwork>
        </figure>
        <texttable anchor="t_2way-aconf-vad_1" title="5.4.2 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109 0 8</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=extmap:1/recvonly urn:ietf:params:rtp-hdrext:csrc-audio-level</c>
          <c><xref target="RFC6465"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref> PCMU Audio Codec</c>
          <c>a=rtpmap:0 PCMA/8000</c>
          <c><xref target="RFC3551"></xref> PCMA Audio Codec</c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref> - Alice can send and recv audio</c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref> </c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref>  </c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:11111 cname:QCL/1HmN4Xa5CClapa</c>
          <c><xref target="RFC5576"/></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="t_2way-aconf-vad_2" title="5.4.2 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref> - Session Origin Information</c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE audio</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref></c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109 0 98</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=mid:audio</c>
          <c><xref target="RFC5888"></xref></c>
          <c>a=msid:ma ta </c>
          <c> Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtcp:60065 IN IP4 98.248.92.77</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=extmap:1/sendonly urn:ietf:params:rtp-hdrext:csrc-audio-level</c>
          <c><xref target="RFC6465"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtpmap:0 PCMU/8000</c>
          <c><xref target="RFC3551"></xref> PCMU Audio Codec</c>
          <c>a=rtpmap:0 PCMA/8000</c>
          <c><xref target="RFC3551"></xref> PCMA Audio Codec</c>
          <c>a=rtcp-fb:* nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
		  <c><xref target="RFC4145"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:
          70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref> </c>
          <c>a=ssrc:2222 cname:HmN4Xa5CC/lapa</c>
          <c><xref target="RFC5576"/></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
      	</section>
      	<section anchor="successful-2way-webrtc-voip"
        title="Successful legacy Interop Fallback with bundle-only">
        <t>In the scenario described below, Alice is a multi-stream capable
        WebRTC endpoint while Bob is a legacy VOIP end-point. The SDP
        Offer/Answer exchange demonstrates successful session setup with
        fallback to audio only stream negotiated via bundle-only framework
        between the end-points. Specifically,
         <list style="symbols">
         	<t>Offer from Alice describes 2 cameras via 2 video m=lines with
         	 both marked as bundle-only.</t>
             <t> Since Bob doesnot recognize either the BUNDLE mechanism or
             the bundle-only attribute, he accepts only the audio stream
             from Alice.</t>
          </list>
        </t>
    <figure>
          <artwork alt="2-Way Legacy Interop">
<![CDATA[
         Successful 2-Way WebRTC <-> VOIP Interop

Alice                                                       Bob
|                                                           |
|                                                           |
|       Alice is a multistream capable WebRTC end-point     |
|          & Bob is behind a legacy VOIP system             |
|                                                           |
|Offer(Audio:Opus Video:2 VP8,2 H2.64 Streams) with         |
|          bundle-only                                      |
|---------------------------------------------------------->|
|     Alice marks both the video streams as bundle-only     |
|                                                           |
|                                                           |
|                  Answer(Audio:Opus)                       |
|<----------------------------------------------------------|
|                                                           |Bob
|                                                           |accepts
|                                                           |audio
|                                                           |stream,
|                                                           |since he
|                                                           |doesn't
|                                                           |recognize
|                                                           |bundle-only
|                                                           |
|                   Two way Opus Audio                      |
|...........................................................|
|                                                           |
|                                                           |

]]></artwork>
        </figure>
       <texttable anchor="t_legacy_interop_1_1"
				title="5.4.3 SDP Simulcast bundle-only">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=msid-semantic:WMS ma</c>
          <c><xref target="I-D.ietf-mmusic-msid"></xref></c>
          <c>a=group:BUNDLE m0 m1 m2</c>
          <c><xref target="I-D.ietf-mmusic-sdp-bundle-negotiation"></xref>
          Alice supports grouping of m=lines under BUNDLE semantics</c>
          <c>a=ice-options:trickle</c>
          <c><xref target="I-D.ietf-mmusic-trickle-ice"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m0</c>
          <c><xref target="RFC5888"></xref> Audio m=line part of BUNDLE group
          with a unique port number</c>
          <c>a=msid:ma ta </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (ta) </c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:actpass</c>
          <c><xref target="RFC4145"></xref> </c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:
          9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx
          raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx
          raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ssrc:11111 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref>E</c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 98 100</c>
          <c>bundle-only video line with port number set to zero  </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m1</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=msid:ma tb </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tb) </c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=imageattr:98 [x=1280,y=720]</c>
          <c><xref target="RFC6236"></xref></c>
          <c>a=fmtp:98 max-fr=30</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=ssrc:12345 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"></xref></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 101 103</c>
          <c>bundle-only video line with port number set to zero  </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtcp:64678 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=mid:m2</c>
          <c><xref target="RFC5888"></xref> Video m=line part of BUNDLE group</c>
          <c>a=msid:ma tc </c>
          <c>Identifies RTCMediaStream ID (ma) and RTCMediaStreamTrack ID (tc) </c>
          <c>a=rtpmap:101 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=rtpmap:103 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:101 profile-level-id=4d0028;packetization-mode=1;max-fr=30 </c>
          <c><xref target="RFC3984"></xref>Camera-2,Encoding-1 Resolution</c>
          <c>a=ssrc:67890 cname:axzo1278npDlAzM73</c>
          <c><xref target="RFC5576"/></c>
          <c>a=bundle-only</c>
          <c><xref target="UNIFIED-PLAN"/> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
        </texttable>
        <texttable anchor="t_legacy_interop_1_2" title="5.4.3 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20519 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>m=audio 49203 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtcp:60065 IN IP4 24.23.204.141</c>
          <c><xref target="RFC3605"></xref></c>
          <c>a=rtpmap:109 opus/48000/2</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level</c>
          <c><xref target="RFC6464"></xref></c>
          <c>a=ptime:20</c>
          <c><xref target="I-D.ietf-payload-rtp-opus"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref> </c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=setup:active</c>
		      <c><xref target="RFC4145"></xref></c>
          <c>a=ice-ufrag:ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:
          70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 98.248.92.77 49203 typ srflx
          raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 98.248.92.77 60065 typ srflx
          raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 98 100</c>
          <c> Bob doesn't recognize bundle-only and hence rejects
          the video stream </c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:98 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=rtpmap:100 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=imageattr:98 [x=1280,y=720]</c>
          <c><xref target="RFC6236"/></c>
          <c>a=fmtp:98 max-fr=30</c>
          <c><xref target="RFC4566"></xref></c>
          <c>m=video 0 UDP/TLS/RTP/SAVPF 98 100</c>
          <c> Bob doesn't recognize bundle-only and hence
          rejects the video stream</c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:101 H264/90000</c>
          <c><xref target="RFC3984"></xref></c>
          <c>a=fmtp:101 profile-level-id=4d0028;packetization-mode=1;max-fr=30 </c>
          <c><xref target="RFC3984"></xref>Camera-2,Encoding-1 Resolution</c>
        </texttable>
      </section>
       <section anchor="sec-2way-webrtc-voip"
        title="Legacy Interop with RTP/AVP profile">
        <t>
     	In this section, we attempt to provide session descriptions showcasing inter-operability
     	between a WebRTC end-point and a Legacy VOIP end-point. The ideas included in here
     	are not fully baked into the standards and might be controversial in nature. The hope here is
     	to demonstrate a plausible SDP composition to enchance seamless inter-operability between the
     	aforementioned communication systems.
        </t>
        <t>
          In the scenario desribed below, Alice is a legacy end-point which sends
          <xref target="RFC3264"></xref> Offer with two sets of media descriptions
          per media type.
          <list>
            <t> One set that correponds to <xref target="WebRTC"></xref> compliant
            UDP/TLS/RTP/SAVPF based audio and video descriptions.
            </t>
            <t> Another set with RTP/AVP based audio and video descriptions for the
            legacy Interop purposes. </t>
            <t>
            Also to note, Alice includes session level DTLS information and media level
            RTCP feedback information as applicable to both the sets of
            media descriptions</t>
          </list>
        </t>
        <t>
          On the other hand, Bob being a WebRTC end-point, recognizes accepts
          the media descriptions with RTP/AVP profile.
          The security and feedback requirements for the session are either handled by a
          intermediate gateway or with some combination of Alice's capabilities and
          the intermediate gateway.
        </t>
        <figure>
          <artwork alt="Successful-Session 2 Way SAVP VOIP">
<![CDATA[
           Successful 2-Way WebRTC <-> VOIP Interop

Alice                                                          Bob
|                                                               |
|                                                               |
|  Alice is a legacy VOIP End-point & Bob is a WebRTC End-Point |
|                                                               |
|                                                               |
|                                                               |
|              Offer(Audio:Opus Video:H.264)                    |
|-------------------------------------------------------------->|
|                                                               |
|                                                               |
|Alice includes 2 copies of media descriptions                  |
|1. WebRTC compliant media description (UDP/TLS/RTP/SAVPF)      |
|2. Legacy compliant media description (RTP/AVP)                |
|                                                               |
|                                                               |
|             Answer(Audio:Opus, Video:H.264)                   |
|<--------------------------------------------------------------|
|                                                               |Bob
|                                                               |accepts
|                                                               |"legacy
|                                                               |compliant"
|                                                               |m=line
|                                                               |
|                                                               |
|             Two way Opus Audio, H.264 Video                   |
|...............................................................|
|       Session also suports RTP/RTCP Mux, RTCP Feedback        |
|                                                               |

]]></artwork>
        </figure>
        <texttable anchor="t_legacy2_1" title="5.4.5 SDP Offer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=- 20518 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=ice-ufrag:074c6550</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:a28a397a4c3f31747d1ee3474af08a068</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-rsize</c>
          <c><xref target="RFC5506"></xref></c>
          <c>m=audio 54609 UDP/TLS/RTP/SAVPF 109</c>
          <c><xref target="RFC4566"></xref></c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:109 opus/48000</c>
          <c><!--<xref target="draft-spittka-payload-rtp-opus"></xref>--></c>
          <c>a=ptime:20</c>
          <c><!--<xref target="draft-spittka-payload-rtp-opus"></xref>--></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54609 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54609 typ srflx raddr 192.168.1.4 rport 54609</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref></c>
          <c>m=video  62537 UDP/TLS/RTP/SAVPF 120</c>
          <c><xref target="RFC4566"></xref> </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref></c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 62537 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1694302207 24.23.204.141 62537 typ srflx raddr 192.168.1.4 rport 62537</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 2113667326 192.168.1.4 54721 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 24.23.204.141 54721 typ srflx raddr 192.168.1.4 rport 54721</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref></c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
          <c>---------------</c>
          <c>These set of media descriptions are for Legacy Inter-op purposes</c>
          <c>m=audio 54732 RTP/AVP 109</c>
          <c><xref target="RFC4566"></xref>Alice includes RTP/AVP audio stream description</c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:7f:7d:f9:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtpmap:109 opus/48000</c>
          <c><!--<xref target="draft-spittka-payload-rtp-opus"></xref>--></c>
          <c>a=ptime:20</c>
          <c><!--<xref target="draft-spittka-payload-rtp-opus"></xref>--></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref>Alice still includes RTP/RTCP Mux support</c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 54732 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  694302207 24.23.204.141 54732 typ srflx raddr 192.168.1.4 rport 54732</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.4 64678 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP  1694302206 24.23.204.141 64678 typ srflx raddr 192.168.1.4 rport 64678</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:109 nack</c>
          <c><xref target="RFC5104"></xref>She adds her intent for NACK RTCP feedback support</c>
          <c>m=video  62445 RTP/AVP 120</c>
          <c><xref target="RFC4566"></xref>Alice includes RTP/AVP video stream description </c>
          <c>c=IN IP4 24.23.204.141</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:7d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=rtcp-mux</c>
          <c><xref target="RFC5761"></xref>Alice intends to perform RTP/RTCP Mux</c>
          <c>a=candidate:0 1 UDP  2113667327 192.168.1.4 62445 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP  1694302207 24.23.204.141 62537 typ srflx raddr 192.168.1.4 rport 62445</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 2113667326 192.168.1.4 54721 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 24.23.204.141 54721 typ srflx raddr 192.168.1.4 rport 54721</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=rtcp-fb:120 nack pli</c>
          <c><xref target="RFC5104"></xref> Alice indicates support for Picture loss Indication and NACK RTCP feedback</c>
          <c>a=rtcp-fb:120 ccm fir</c>
          <c><xref target="RFC5104"></xref></c>
        </texttable>
        <texttable anchor="t_legacy2_2" title="5.4.5 SDP Answer">
          <ttcol align='left'>SDP Contents </ttcol>
          <ttcol align='left'>RFC#/Notes</ttcol>
          <c>v=0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>o=-  16833 0 IN IP4 0.0.0.0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>s=-</c>
          <c><xref target="RFC4566"></xref></c>
          <c>t=0 0</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=ice-ufrag:c300d85b</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=ice-pwd:de4e99bd291c325921d5d47efbabd9a2</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=fingerprint:sha-1 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70:9d:1f:66:79:a8:07</c>
          <c><xref target="RFC5245"></xref></c>
          <c>m=audio 49203 RTP/AVP 109</c>
          <c><xref target="RFC4566"></xref> Bob accepts RTP/AVP based audio stream</c>
          <c>c=IN IP4 98.248.92.77</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:109 opus/48000</c>
          <c><!--<xref target="draft-spittka-payload-rtp-opus"></xref>--></c>
          <c>a=ptime:20</c>
          <c><!--<xref target="draft-spittka-payload-rtp-opus"></xref>--></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 49203 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 49203 typ srflx raddr 192.168.1.7 rport 49203</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 60065 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 98.248.92.77 60065 typ srflx raddr 192.168.1.7 rport 60065</c>
          <c><xref target="RFC5245"></xref></c>
          <c>m=video  63130 RTP/SAVP 120</c>
          <c><xref target="RFC4566"></xref> Bob accepts RTP/AVP based video stram </c>
          <c>c=IN IP4 98.248.92.771</c>
          <c><xref target="RFC4566"></xref></c>
          <c>a=rtpmap:120 VP8/90000</c>
          <c><xref target="I-D.ietf-payload-vp8"></xref></c>
          <c>a=sendrecv</c>
          <c><xref target="RFC3264"></xref></c>
          <c>a=candidate:0 1 UDP 2113667327 192.168.1.7 63130 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 1 UDP 1694302207 98.248.92.77 63130 typ srflx raddr 192.168.1.7 rport 63130</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:0 2 UDP 2113667326 192.168.1.7 56607 typ host</c>
          <c><xref target="RFC5245"></xref></c>
          <c>a=candidate:1 2 UDP 1694302206 98.248.92.77 56607 typ srflx raddr 192.168.1.7 rport 56607</c>
          <c><xref target="RFC5245"></xref></c>
        </texttable>
      </section>
      </section>
    </section>
    <section title="IANA Considerations">
      <t>This document requires no actions from IANA.</t>
    </section>
    <section title="Acknowledgments">
      <t>
        We would like to thank Justin Uberti, Chris Flo for their detailed
				review and inputs.
      </t>
    </section>
    <section title="Change Log">
      <t>[RFC EDITOR NOTE: Please remove this section when publishing]</t>
      <t>Changes from draft-nandakumar-rtcweb-sdp-08
          <list style="symbols">
              <t> Fixed typos </t>
              <t> Moved to a WG version </t>
         </list>
      </t>
      <t>Changes from draft-nandakumar-rtcweb-sdp-06 and draft-nandakumar-rtcweb-sdp-07
          <list style="symbols">
              <t> Added clarification on Call-Flow diagram usage</t>
              <t> More cleanups </t>
         </list>
      </t>
      <t>Changes from draft-nandakumar-rtcweb-sdp-05
          <list style="symbols">
              <t> Added Ascii chart for all the SDP Eaxamples </t>
              <t> Improved text and updated SDP Examples for Simulcast and
							 FEC</t>
              <t> Fixed MediaStream ID Semantics SDP Errors </t>
         </list>
      </t>
      <t>Changes from draft-nandakumar-rtcweb-sdp-04
          <list style="symbols">
              <t> Interim version of the draft to avert expiry </t>
              <t> Corrected placement of c= line as per RFC4566 </t>
              <t> Updated simulcast SDP to reflect
								draft-westerlund-avtcore-rtp-simulcast-04</t>
          </list>
      </t>
      <t>Changes from draft-nandakumar-rtcweb-sdp-03
        <list style="symbols">
          <t> Aligned more closely with JSEP version -05 </t>
          <t> Added Conventions to help readability </t>
          <t> Add more examples to clarify BUNDLE use-cases </t>
        </list>
      </t>
      <t>Changes from draft-nandakumar-rtcweb-sdp-02
        <list style="symbols">
          <t> Major refactoring was done to group the examples in to
						categories </t>
          <t> SDP was updated through out to reflect JSEP-04 style of defining
              attributes per m=line than at the session level. </t>
          <t> Added 8 new examples. </t>
          <t> Updated references for Trickle, Unified Plan </t>
          <t> Add section to explain the syntax conventions followed in the
              examples. </t>
        </list>
      </t>
      <t>Changes from draft-nandakumar-rtcweb-sdp-01
        <list style="symbols">
          <t>Updated references to OPUS RTP Payload Specification.</t>
          <t>Updated BUNDLE examples based on the latest
             draft-ietf-mmusic-sdp-bundle-negotiation.</t>
          <t>Added examples for multiple audio and video flows based on
             Unified Plan.</t>
          <t>Added new examples for RTX and FEC streams </t>
          <t>Updated Simulcast and SVC examples</t>
        </list>
      </t>
      <t>Changes from draft-nandakumar-rtcweb-sdp-00
        <list style="symbols">
          <t>Fixed editorial comments on the mailing list.</t>
          <t>Updated Data-channel SDP information based on
						draft-ietf-mmusic-sctp-sdp.</t>
          <t>Updated BUNDLE examples based on
						draft-ietf-mmusic-sdp-bundle-negotiation.</t>
          <t>Added examples for few more BUNDLE variants</t>
          <t>Added new examples for Simulcast and SVC</t>
        </list>
      </t>
    </section>
  </middle>

  <back>
    <references title="Informative References">
    	&RFC3264;
    	&RFC4145;
    	&RFC4566;
      &RFC2119;
      &RFC5245;
      &RFC5506;
      &RFC3551;
      &RFC3952;
      &RFC4796;
      &RFC5761;
      &RFC3556;
      &RFC5104;
      &RFC4588;
      &RFC5956;
      &RFC5888;
      &RFC6236;
      &RFC3984;
      &RFC5583;
      &RFC5576;
      &RFC3550;
      &RFC3261;
      &RFC2326;
      &RFC3605;
      &RFC2833;
      &RFC6464;
      &RFC6465;
      &RFC7022;
      &I-D.ietf-mmusic-sdp-bundle-negotiation;
      &I-D.ietf-mmusic-sdp-simulcast;
      &I-D.ietf-payload-rtp-opus;
      &I-D.ietf-payload-vp8;
      &I-D.ietf-rtcweb-jsep;
      &I-D.ietf-mmusic-trickle-ice;
      &I-D.ietf-mmusic-msid;
      &I-D.ietf-mmusic-sctp-sdp;
    	&I-D.ietf-rtcweb-data-channel;

      <reference anchor="WebRTC">
        <front>
          <title>
            WebRTC 1.0: Real-time Communication Between Browsers
          </title>
          <author fullname="" initials="" surname="">
            <organization>
              W3C
            </organization>
          </author>
          <date year="" month=""/>
        </front>
        <seriesInfo name="<http://dev.w3.org/2011/webrtc/editor/webrtc.html>" value=""/>
      </reference>
      <reference anchor="UNIFIED-PLAN">
        <front>
          <title> A Unified Plan for Using SDP with Large Numbers of Media Flows</title>
          <author fullname="Adam B Roach" initials="A.B." surname="Roach">
            <organization></organization>
          </author>
          <author fullname="Justin Uberti" initials="J." surname="Uberti">
            <organization></organization>
          </author>
          <author fullname="Martin Thomson" initials="M." surname="Thomson">
            <organization></organization>
          </author>
          <date month="July" year="2013" />
        </front>
        <seriesInfo name="Internet-Draft"
          value="draft-roach-mmusic-unified-plan" />
        <format target="http://tools.ietf.org/html/draft-roach-mmusic-unified-plan-00"
          type="TXT" />
      </reference>
      </references>
  </back>
</rfc>

PAFTECH AB 2003-20262026-04-23 19:32:39