One document matched: draft-bellagamba-ccamp-rsvp-te-mpls-tp-oam-ext-03.xml


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<rfc category="std" docName="draft-bellagamba-ccamp-rsvp-te-mpls-tp-oam-ext-03"
     ipr="trust200902">
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  <!-- ***** FRONT MATTER ***** -->

  <front>
    <!-- The abbreviated title is used in the page header - it is only necessary if the 
         full title is longer than 39 characters -->

    <title abbrev="RSVP-TE Ext for MPLS-TP OAM Config">RSVP-TE Extensions for
    MPLS-TP OAM Configuration</title>

    <!-- add 'role="editor"' below for the editors if appropriate -->

    <!-- Another author who claims to be an editor -->

    <author fullname="Elisa Bellagamba" initials="E.B." role="editor"
            surname="Bellagamba">
      <organization>Ericsson</organization>

      <address>
        <postal>
          <street>Farogatan 6</street>

          <!-- Reorder these if your country does things differently -->

          <city>Kista</city>

          <region></region>

          <code>164 40</code>

          <country>Sweden</country>
        </postal>

        <phone>+46 761440785</phone>

        <email>elisa.bellagamba@ericsson.com</email>

        <!-- uri and facsimile elements may also be added -->
      </address>
    </author>

    <author fullname="Loa Andersson" initials="L.A." role="editor"
            surname="Andersson">
      <organization>Ericsson</organization>

      <address>
        <postal>
          <street>Farogatan 6</street>

          <!-- Reorder these if your country does things differently -->

          <city>Kista</city>

          <region></region>

          <code>164 40</code>

          <country>Sweden</country>
        </postal>

        <phone></phone>

        <email>loa.andersson@ericsson.com</email>

        <!-- uri and facsimile elements may also be added -->
      </address>
    </author>

    <author fullname="Pontus Skoldstrom" initials="P.S." role=""
            surname="Skoldstrom">
      <organization>Acreo AB</organization>

      <address>
        <postal>
          <street>Electrum 236</street>

          <!-- Reorder these if your country does things differently -->

          <city>Kista</city>

          <region></region>

          <code>164 40</code>

          <country>Sweden</country>
        </postal>

        <phone>+46 8 6327731</phone>

        <email>pontus.skoldstrom@acreo.se</email>

        <!-- uri and facsimile elements may also be added -->
      </address>
    </author>


    <!-- If the month and year are both specified and are the current ones, xml2rfc will fill 
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    <!-- Meta-data Declarations -->

    <date day="23" month="October" year="2009" />
    <area>Signaling</area>
    <workgroup>CCAMP Working Group</workgroup>
    <keyword>RSVP-TE</keyword>
    <keyword>GMPLS</keyword>
    <keyword>MPLS-TP</keyword>

    <abstract>
      <t>This document defines a method for the configuration of MPLS Transport Profile (MPLS-TP) Operations, 
	Administration and Maintenance (OAM) functionalities through 
	extensions to RSVP-TE.</t>
    </abstract>
  </front>

  <middle>
    <section title="Introduction">
  
      <t>This document defines a method for the configuration of MPLS Transport Profile (MPLS-TP) Operations, 
	Administration and Maintenance (OAM) functionalities through 
	extensions to RSVP-TE.</t>
      
      <t>The procedures included describe Bidirectional Forwarding Detection 
	(BFD) configuration for Continuity Check (CC) and Connection Verification (CV).  
	Updated versions of this document will describe the configuration of the remaining MPLS-TP OAM
	functionalities.</t>
      
      <t>The future updates of this document are meant to proceed consequently to the upcoming 
	MPLS-TP documents defining the MPLS-TP specific OAM functionalities and with [MPLS-TP-IDENTIF]
	which specifies identifiers for MPLS-TP objects.</t>
      
      <section title="Contributing Authors"> 
	<t>The editors gratefully acknowledge the precious contributions of Lou Berger,
	  Annamaria Fulignoli, Andras Kern, David Jocha, David Sinicrope, Attila Takacs and 
	  Benoit Tremblay.</t>
      </section>
   
      <section title ="Requirements Language">
	<t>
	  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
	  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
	  document are to be interpreted as described in <xref
							    target="RFC2119">RFC 2119</xref>.
	</t>
      </section>

      <section title="Background"> 
	<t>MPLS Transport Profile (MPLS-TP), describes a profile of MPLS that enables operational 
	  models typical in transport networks, while providing additional OAM, survivability and 
	  other maintenance functions not currently supported by MPLS.</t>

	<t>For the cases where a control plane is used with MPLS-TP, the GMPLS control plane, 
	  RSVP-TE [RFC3471] and/or OSPF-TE [RFC3630] ISIS-TE [5307] has been chosen to support the
	  establishment of MPLS-TP LSPs.</t>
	
	<t>[MPLS-TP-OAM-REQ] defines the requirements by which the OAM functionality of 
	  MPLS-TP should abide.</t>
	
	<t>The MPLS-TP design team provided recommendations regarding the functionalities that should 
	  be covered by the existing toolsets and which extensions or new tools will be needed in order 
	  to provide full coverage of the OAM functionalities for MPLS-TP. 
	  A detailed overview of the adopted OAM tools will be documented in 
	  [MPLS-TP OAM Analysis].</t>
	
	<t>This document provides extensions to RSVP-TE in order to accommodate
	  the MPLS-TP CC (Continuity Check) and CV (Connectivity Verification)
	  MPLS-TP OAM functionalities.  Further revisions of this document
	  will describe RSVP-TE extensions for the other MPLS-TP OAM
	  functionalities as needed.</t>
	
	<t>Bidirectional Forwarding Detection (BFD), as described in [BFD], defines a
	  protocol that provides low-overhead, short-duration detection of
	  failures in the path between two forwarding engines, including the
	  interfaces, data link(s), and to the extent possible the forwarding
	  engines themselves. BFD can be used to track the liveliness of
	  MPLS-TP point-to-point and p2mp connections and detect data plane
	  failures. This version of the draft is focused on unidirectional and
	  bidirectional p2p connection.</t>

	<t>BFD has been chosen to cover MPLS-TP CC functionality.</t>

	<t>An extended version of BFD, as described in [BFD-CV], has been chosen 
	  to accomplish both MPLS-TP CC and CV.</t>

      </section>
    </section>


    
    <section title="Overview of BFD OAM operation">
      <t>BFD is a simple hello protocol that in many respects is similar to the detection 
	components of well-known routing protocols. A pair of system transmits BFD packets 
	periodically over each path between the two systems, and if a system stops receiving 
	BFD packets for long enough, some component in that particular bidirectional path to 
	the neighboring system is assumed to have failed. Systems may also negotiate to not 
	send periodic BFD packets in order to reduce overhead.</t>

      <t>A path is only declared to be operational when two-way communication has been 
	established between systems, though this does not preclude the use of unidirectional links.</t>

      <t>[BFD] sect. 3 states that a separate BFD session is created for each 
	communications path and data protocol in use between two systems.</t>

      <t>Each system estimates how quickly it can send and receive BFD packets 
	in order to come to an agreement with its neighbor about how rapidly detection 
	of failure will take place.  These estimates can be modified in real time in order 
	to adapt to unusual situations. This design also allows for fast systems on a shared 
	medium with a slow system to be able to more rapidly detect failures between the fast 
	systems while allowing the slow system to participate to the best of its ability.</t>

      <t>The ability of each system to control the BFD packet transmission rate 
	in both directions provides a mechanism for congestion control, particularly 
	when BFD is used across multiple network hops.</t>

      <t>As recommended in [BFD-CV], the BFD tool needs to be extended for the CV functionality 
	by the addition of a unique identifier in order to meet the requirements. 
	The document in [BFD-CV] specifies the BFD extension and behavior to meet the requirements 
	for MPLS-TP proactive Continuity Check and Connectivity Verification functionality and 
	the RDI functionality as defined in [MPLS-TP-OAM-REQ].</t>


    </section>

    <section title="RSVP-TE Extensions">
      <section title="Operation overview">

	<t>Below, extension to RSVP-TE for setting up BFD or BFD extended version are defined 
	  in order to configure MPLS-TP CC and CV OAM functionalities during the LSP setup.</t>

	<t>The terms "ingress LER" and "egress LER" will not refer in this document to any 
	  direction in the forwarding plane, but only to the LER triggering the LSP setup 
	  (ingress LER) and the one triggering the response to it (egress LER).</t>

	<t>During the LSP signaling, the Control Plane instance in the ingress and the egress LER 
	  announces the BFD OAM Configuration TLV (inside the LSP_ATTRIBUTES object carried by the 
	  Path and Resv message respectively), which includes the "Local Discriminator" sub-TLV.
	  During the BFD session the ingress LER will use as "MyDiscriminator" the value announced in the 
	  "Local Discriminator"(Path message) and as "YourDiscriminator" the value received in the 
	  "Local Discriminator" (Resv message).</t>

	<t>The system initiating the signaling MUST advertise the interval value at which it 
	  requires BFD control packets both in transmission and reception. If the receiving system 
	  can not support this value, a new value can be signaled back in the Resv message, with 
	  the constraint that the new value MUST be comprised between the Maximum and Minimum values 
	  indicated by the ingress. If the egress system can not support any value in the indicated 
	  range, it will reply with an error.</t>

	<t>In the case BFD extended version should be configured, the unique MEP ID parameter 
	  MUST be included along with the Discriminator and timing values as described in the 
	  following sections.</t>

      </section>

      <section title="OAM Configuration TLV">
        <t>Below is reported the "OAM Configuration TLV", defined in [OAM-CONF-FWK]. 
	  It specifies which OAM technology/method should be used for the LSP. The OAM 
	  Configuration TLV is carried in the LSP_ATTRIBUTES object in Path messages.</t>

	<t>
          <figure>
            <artwork><![CDATA[ 

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |           Type (2) (IANA)     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    OAM Type   |   Reserved    |         OAM Function          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                           sub-TLVs                            ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                
			  
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>

	<t>Type: indicates the OAM Configuration TLV (2) (IANA to assign).</t>

	<t>OAM Type: one octect that specifies the technology specific OAM Type. If the
	  requested OAM Type is not supported an error must be generated:
	  "OAM Problem/Unsupported OAM Type".</t>

	<t>In this document a new OAM Type - OAM Type 2 - is defined: MPLS-TP OAM.</t>

        <texttable align="center" anchor="table_example" suppress-title="true"
                   title="">
          <ttcol align="left">OAM Type</ttcol>

          <ttcol align="left">Description</ttcol>

          <c>0</c>

          <c>Reserved</c>

          <c>1</c>

          <c>Ethernet OAM</c>

          <c>2 </c>

          <c>MPLS-TP OAM</c>

          <c>3-256</c>

          <c>Reserved</c>

          <postamble>The receiving node when the BFD OAM Type is requested
          should look for the corresponding technology specific BFD OAM
          configuration TLV.</postamble>
        </texttable>

	<t>OAM Function Flags: a two octect field that specifies pro-active OAM 
	  functions that should be established and configured. If the selected 
	  OAM Function(s) is(are) not supported an error must be generated: 
	  "OAM Problem/Unsupported OAM Function". </t>

	<t>The Flag 0 was already in use for "Connectivity Monitoring" 
	  and it will be used in this document to establish MPLS-TP Continuity 
	  Check (CC) functionality. A new Flag 3 is defined here and will be used 
	  to establish MPLS-TP Continuity Check and Connectivity Verification (CC & CV) 
	  functionality. Control Plane control of on Demand functions are for further studies.</t>

	<t>The following table summarizes the Flags usage.</t>

        <texttable align="center" anchor="table_flags" suppress-title="true"
                   title="">
          <ttcol align="left">OAM Type</ttcol>

          <ttcol align="left">Description</ttcol>

          <c>0</c>

          <c>Continuity Check (CC)</c>

          <c>1</c>

          <c>Reserved</c>

          <c>2 </c>

          <c>Reserved</c>

          <c>3</c>

          <c>Continuity Check and Connectivity Verification (CC&CV)</c>

          <c>4-16</c>

          <c>Reserved</c>

          <postamble></postamble>
        </texttable>
	
	<t>The receiving LER when the MPLS-TP OAM Type is requested 
	  should check which Flags are set and look for
	  the corresponding technology specific configuration TLV.</t>

	<t><list>
	    <t>- "BFD CC OAM Configuration TLV" which MUST be used if Flag = 0 for
	      configuring BFD for setting up the proactive MPLS-TP CC OAM tool
	      (TLV type = 4, IANA to define);</t>
	    <t>- "BFD CC&CV OAM Configuration TLV" which MUST be used if Flag = 3 for
	      configuring BFD for setting up the proactive MPLS-TP CC&CV OAM
	      tool (TLV type = 5, IANA to define).</t>
	</list></t>

	<t>In case the receiving LER does not support the CC&CV functionality, 
	  an error "OAM Problem/Unsupported BFD functionality" must be generated when receiving 
	  the BFD CC&CV OAM Configuration TLV.</t>

      </section>

      <section title="BFD CC OAM Configuration TLV">
	<t>The BFD CC OAM Configuration TLV (depicted below) is defined for BFD OAM
	  specific configuration parameters. The BFD CC OAM Configuration TLV is
	  carried as a sub-TLV of the "OAM Configuration TLV" in the LSP_ATTRIBUTES object both in Path 
	  and Resv messages.</t>

	<t>This new TLV accommodates generic BFD OAM information and carries
	  sub-TLVs.</t>

	<t>
          <figure>
            <artwork><![CDATA[ 
    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |           Type (4) (IANA)     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Vers.|R|         Reserved (set to all 0s)                      |      
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                           sub TLVs                            ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                  
			  
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>



	<t>Type: indicates a new type, the "BFD CC OAM 
	  Configuration TLV" (4) (IANA to define).</t>

	<t>Length: indicates the total length including sub-TLVs.</t>

	<t>Version: identifies the BFD protocol version. If a node does not 
	  support a specific BFD version an error must be generated: 
	   “OAM Problem/Unsupported OAM Version ”</t>

	<t>R Flag: Role Flag. If set, the receiving node is required to 
	  act with an Active Role as described in [BFD] sect. 6.1. 
	  When the BFD OAM Configuration TLV is carried in the Resv message, 
	  the flag is not taken into consideration by the receiving node.</t>   

	<t>The BFD CC OAM Configuration TLV MUST include the following sub-TLVs
	  in the Path message:</t>

	<t><list>
	    <t>- "Local Discriminator" sub-TLV;</t>
	    <t>- "Suggested TX interval" sub-TLV.</t>
	</list></t>

	<t>The BFD CC OAM Configuration TLV MUST include the following 
	  sub-TLVs in the Resv message:</t>

	<t><list>
	    <t>- "Local Discriminator" sub-TLV;</t>
	    <t>- "Suggested TX interval" sub-TLV if a different timing 
	      value needs to be used.</t>
	</list></t>

      <section title="Local Discriminator sub-TLV">

	<t>The Local Discriminator sub-TLV is depicted below.</t>

	<t>
          <figure>
            <artwork><![CDATA[ 
    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |           Type (1) (IANA)     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    		  Local Discriminator                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>

	<t>Type: indicates a new type, the Local Discriminator sub TLV (1) 
	  (IANA to define).</t>

	<t>Length: indicates the total length of the TLV including padding as defined in [BFD].</t>

	<t>Local Discriminator: A unique, nonzero discriminator value 
	  generated by the transmitting system and referring to itself, 
	  used to demultiplex multiple BFD sessions between the same pair of systems. 
	  This Discriminator will be signaled both by the ingress LSR and the egress 
	  LSR in the Path and Resv message respectively.</t>
          
      </section>

      <section title="Suggested TX interval">
	<t>The Suggested TX interval sub-TLV is depicted below.</t>

	<t>
          <figure>
            <artwork><![CDATA[ 
       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Req. TX int. Type (2) (IANA) |          Length = 24          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   	Acceptable Min. Asynchronous TX interval              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Suggested Asynchronous TX interval               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |		Acceptable Max. Asynchronous TX interval	      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |               Required Echo TX Interval                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Detect. Mult |           Reserved                            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>

    <t>Type: indicates a new type, the Suggested TX interval sub TLV (3) 
      (IANA to define).</t>

    <t>Length: indicates the total length of the TLV including padding, it is set to 24 (octects).</t>

    <t>Suggested Asynchronous TX interval: the interval, in microseconds, that the system initiating 
      the signaling want to have when both transmitting and receiving BFD Control packets, less any 
      jitter applied. The value zero is reserved. If the receiving system can not support this value, 
      a new value can be signaled back in the Resv message, with the constraint that the new value will 
      be not higher than "Acceptable Max. Asynchronous TX interval" and not lower than "Acceptable 
      Min. Asynchronous TX interval".</t>

    <t>Acceptable Min. Asynchronous TX interval: the maximum TX interval, in microseconds, 
      that the system initiating the signaling can support. In case the receiving system 
      sends back this TLV for proposing a different "Suggested Asynchronous TX interval", the 
      "Acceptable Min. Asynchronous TX interval" will not be taken into consideration by the system 
      which initiated the signaling.</t>

    <t>Acceptable Max. Asynchronous TX interval: the minimum TX interval, in microseconds, 
      that the system initiating the signaling can support. In case the receiving system 
      sends back this TLV for proposing a different "Suggested Asynchronous TX interval", 
      the "Acceptable Max. Asynchronous TX interval" will not be taken into consideration 
      by the system which initiated the signaling.</t>

    <t>Required Echo TX Interval: the minimum interval, in microseconds,
      between received BFD Echo packets that this system is capable of
      supporting, less any jitter applied by the sender as described in
      [BFD] sect. 6.8.9.  This value is also an indication for the
      receiving system of the minimum interval between transmitted BFD Echo
      packets.  If this value is zero, the transmitting system does not
      support the receipt of BFD Echo packets.  If the receiving system can
      not support this value an error MUST be generated "Unsupported BFD TX rate interval"</t>
      </section>
    </section>


    <section title="BFD CC&CV OAM Configuration TLV">
    <t>The BFD CC&CV OAM Configuration TLV (depicted below) is defined for BFD OAM
      specific configuration parameters. The BFD CC&CV OAM Configuration TLV is
      carried as a sub-TLV of the "OAM Configuration TLV" in the LSP_ATTRIBUTES 
      object both in Path and Resv messages.</t>

    <t>This new TLV accommodates generic BFD OAM information and carries
      sub-TLVs.</t>

	<t>
          <figure>
            <artwork><![CDATA[ 
       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   BFD CC&CV  Type (5) (IANA)  |           Length              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |Vers.|R|         Reserved (set to all 0s)                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      ~                           sub TLVs                            ~
      |                                                               | 
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>

	<t>Type: indicates a new type, the BFD CC&CV OAM Configuration TLV (5) (IANA
	  to define).</t>

	<t>Length: indicates the TLV total length (in octects) including sub-TLVs.</t>

	<t>Version: identifies the BFD protocol version. If a node does not support a specific 
	  BFD version an error must be generated: "OAM Problem/Unsupported OAM Version"</t>

	<t>R Flag: Role Flag.  If set, the receiving node is required to act
	  with an Active Role as described in [BFD] sect. 6.1.  When the BFD
	  OAM Configuration TLV is carried in the Resv message, the flag it not
	  taken into consideration by the receiving node.</t>

	<t>The BFD CC&CV OAM Configuration TLV MUST include the following 
	  sub-TLVs in the Path message:</t>

	<t><list>
	    <t>- "Local Discriminator" sub-TLV;</t>
	    <t>- "Suggested TX interval" sub-TLV;</t>
	    <t>- "Source unique MEP-ID" sub-TLV.</t>
	</list></t>

	<t>The BFD CC&CV OAM Configuration TLV MUST include the following sub-TLVs 
	  in the Resv message:</t>

	<t><list>
	    <t>- "Local Discriminator" sub-TLV;</t>
	    <t>- "Suggested TX interval" sub-TLV if a different timing value 
	      needs to be used;</t>
	    <t>- "Source unique MEP-ID" sub-TLV.</t>
	</list></t>	

	<section title="Source unique MEP-ID sub-TLV">
	  <t>The MPLS Generic Associated Channel specification (see[RFC5586] sect. 3) 
	    describes the ACH TLV structure that can be used to provide additional 
	    context information to the G-ACh packet.</t>

	  <t>In this section it is showed how the "Source unique MEP-ID" sub-TLV in the BFD CC&CV OAM Configuration 
	    TLV can be used to configure the TLV Objects in the ACH TLV for providing the MEP 
	    Identifier information and the ME Identifier information as required by[MPLS-TP-OAM-FWK].</t>

	<t>
          <figure>
            <artwork><![CDATA[ 
    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Source unique MEP-ID Type (3)(IANA)|         Length            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                  Source unique MEP-ID                         ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>

	  <t>Length: indicates the TLV total length (in octects) including sub-TLVs.</t>

	  <t>Source unique MEP-ID: the unique MEP Identifier of the source of the BFD 
	    packet. Please refer to [MPLS-TP-IDENTIF] for a detailed explanation of the field 
	    composition and to possible changes of the field definition. As the 
	    writing time, the "Source unique MEP-ID" is defined 
	    to be the Network_IF_ID. The Network_IF_ID is also defined in [MPLS-TP-IDENTIF], 
	    section 4.</t>

	</section>

    </section>
    </section>

    <!-- Possibly a 'Contributors' section ... -->

    <section anchor="IANA" title="IANA Considerations">
      <t>This document specifies the following new TLV types.</t>

      <t> sub-TLVs types to be carried in the OAM Configuration TLV in LSP_ATTRIBUTES:</t>

      <t><list>
	  <t>- "BFD CC OAM Configuration" sub-TLV type: 4</t>
	  
	  <t>- "BFD CC&CV OAM Configuration" sub-TLV type (to be carried 
	    in the OAM Configuration TLV in LSP_ATTRIBUTES): 5</t>
	</list> 
      </t>
      
      <t> sub-TLV types to be carried in the BFD OAM Configuration sub-TLV:</t>
	<t><list>
	  <t>- "Local Discriminator" sub-TLV type: 1</t>
	  <t>- "Suggested TX interval" sub-TLV type: 2</t>
	  <t>- "Source unique MEP-ID" sub-TLV type: 3 </t>
      </list> </t>
    
    </section>

    <section title="BFD OAM configuration errors">
      <t>In addition to error values specified in [OAM-CONF-FWK] and [ETH-OAM] 
	this document defines the following values for the "OAM Problem" Error Code:</t>

      <t><list>
	  <t>- "OAM Problem/Unsupported BFD functionality"</t>
	  <t>- "OAM Problem/Unsupported BFD TX rate interval"</t>
	  <t>- "OAM Problem/Unsupported MEP ID Format" </t>
	</list>
      </t>

    </section>

    <section anchor="Security" title="Security Considerations">
      <t>The signaling of OAM related parameters and the automatic establishment of OAM 
	entities introduces additional security
	considerations to those discussed in [RFC3473].  In particular, a
	network element could be overloaded, if an attacker would request
	liveliness monitoring, with frequent periodic messages, for a high
	number of LSPs, targeting a single network element.</t>

      <t>Security aspects will be covered in more detailed in subsequent
	versions of this document.</t>
    </section>
  </middle>

  <!--  *****BACK MATTER ***** -->

  <back>
    <!-- References split into informative and normative -->

    <!-- There are 2 ways to insert reference entries from the citation libraries:
     1. define an ENTITY at the top, and use "ampersand character"RFC2629; here (as shown)
     2. simply use a PI "less than character"?rfc include="reference.RFC.2119.xml"?> here
        (for I-Ds: include="reference.I-D.narten-iana-considerations-rfc2434bis.xml")

     Both are cited textually in the same manner: by using xref elements.
     If you use the PI option, xml2rfc will, by default, try to find included files in the same
     directory as the including file. You can also define the XML_LIBRARY environment variable
     with a value containing a set of directories to search.  These can be either in the local
     filing system or remote ones accessed by http (http://domain/dir/... ).-->

    <references title="Normative References">
      <!--?rfc include="http://xml.resource.org/public/rfc/bibxml/reference.RFC.2119.xml"?-->

      <?rfc include="reference.RFC.3471"?>
      <?rfc include="reference.RFC.2119"?>
      <?rfc include="reference.RFC.5586"?>
      <?rfc include="reference.RFC.4447"?>


      <reference anchor="MPLS-TP-OAM-REQ"
		 target="draft-ietf-mpls-tp-oam-requirements">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>Requirements for OAM in MPLS Transport Networks</title>

          <author initials="M" surname="Vigoureux">
            <organization></organization>
          </author>

          <author initials="D" surname="Ward">
            <organization></organization>
          </author>

          <author initials="M" surname="Betts">
            <organization></organization>
          </author>

          <date year="2009" />
        </front>
      </reference>

      <reference anchor="BFD"
		 target="draft-ietf-bfd-base">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>Bidirectional Forwarding Detection</title>

          <author initials="D" surname="Katz">
            <organization></organization>
          </author>

          <author initials="D" surname="Ward">
            <organization></organization>
          </author>

          <date year="2009" />
        </front>
      </reference>

      <reference anchor="OAM-CONF-FWK"
		 target="draft-ietf-ccamp-oam-configuration-fwk">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>OAM Configuration Framework for GMPLS RSVP-TE</title>

          <author initials="A" surname="Takacs">
            <organization></organization>
          </author>

          <author initials="D" surname="Fedyk">
            <organization></organization>
          </author>

          <author initials="J" surname="van He">
            <organization></organization>
          </author>

          <date year="2009" />
        </front>
      </reference>

      <reference anchor="BFD-CV"
		 target="draft-asm-mpls-tp-bfd-cc-cv">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>MPLS-TP BFD for Proactive CC-CV and RDI</title>

          <author initials="A" surname="Fulignoli">
            <organization></organization>
          </author>

          <author initials="S" surname="Boutros">
            <organization></organization>
          </author>

          <author initials="M" surname="Vigoreux">
            <organization></organization>
          </author>

          <date year="2009" />
        </front>
      </reference>

      <reference anchor="MPLS-TP-OAM-FWK"
		 target="draft-ietf-mpls-tp-oam-framework">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>MPLS-TP OAM Framework and Overview</title>

          <author initials="I" surname="Busi">
            <organization></organization>
          </author>

          <author initials="B" surname="Niven-Jenkins">
            <organization></organization>
          </author>

          <date year="2009" />
        </front>
      </reference>

      <reference anchor="MPLS-TP-IDENTIF"
		 target="draft-swallow-mpls-tp-identifiers">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>MPLS-TP Identifiers</title>

          <author initials="M" surname="Bocci">
            <organization></organization>
          </author>

          <author initials="G" surname="Swallow">
            <organization></organization>
          </author>

          <date year="2009" />
        </front>
      </reference>

    </references>

    <references title="Informative References">

      <reference anchor="ETH-OAM"
		 target="draft-ietf-ccamp-rsvp-te-eth-oam-ext">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>GMPLS RSVP-TE Extensions for Ethernet OAM</title>

          <author initials="A" surname="Takacs">
            <organization></organization>
          </author>

          <author initials="B" surname="Gero">
            <organization></organization>
          </author>

          <author initials="D" surname="Fedyk">
            <organization></organization>
          </author>

          <author initials="D" surname="Mohan">
            <organization></organization>
          </author>

          <author initials="D" surname="Long">
            <organization></organization>
          </author>

          <date year="2009" />
        </front>
      </reference>

        <reference anchor="MPLS-TP OAM Analysis"
		 target="draft-sprecher-mpls-tp-oam-analysis">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>MPLS-TP OAM Analysis</title>

          <author initials="N" surname="Sprecher">
            <organization></organization>
          </author>

          <author initials="T" surname="Nadeau">
            <organization></organization>
          </author>

          <author initials="H" surname="van Helvoort">
            <organization></organization>
          </author>

          <author initials="" surname="Weingarten">
            <organization></organization>
          </author>

          <date year="2006" />
        </front>
      </reference>

      <reference anchor="LSP Ping"
		 target="RFC 3479">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>Detecting Multi-Protocol Label Switched (MPLS) Data Plane Failures</title>

          <author initials="K" surname="Kompella">
            <organization></organization>
          </author>

          <author initials="G" surname="Swallow">
            <organization></organization>
          </author>

          <date year="2006" />
        </front>
      </reference>


    </references>

    <section anchor="app-additional" title="Additional Stuff">
      <t>This becomes an Appendix.</t>
    </section>

  </back>
</rfc>

PAFTECH AB 2003-20262026-04-23 09:49:29