One document matched: draft-ietf-ccamp-rsvp-te-mpls-tp-oam-ext-05.xml


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<rfc category="std" docName="draft-ietf-ccamp-rsvp-te-mpls-tp-oam-ext-05"
     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="Extensions for MPLS-TP OAM Conf">Configuration of pro-active MPLS-TP Operations, Administration, and Maintenance (OAM) Functions Using RSVP-TE</title>

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

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

    <author fullname="Elisa Bellagamba" initials="E." 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." 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>
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    <author fullname="Pontus Skoldstrom" initials="P." role="editor"
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      <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>
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      </address>
    </author>

    <author fullname="Dave Ward" initials="D." role=""
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      <organization>Juniper</organization>
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          <street></street>
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        <email>dward@juniper.net</email>
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      </address>
    </author>


    <author fullname="Attila Takacs" initials="A." role=""
            surname="Takacs">
      <organization>Ericsson</organization>

      <address>
        <postal>
          <street>1. Laborc u.
          </street>

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

          <city>Budapest</city>

          <region></region>
          <code></code>

          <country>HUNGARY</country>
        </postal>
        <phone></phone>

        <email>attila.takacs@ericsson.com</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="10" month="March" year="2011" />
    <area>Signaling</area>
    <workgroup>CCAMP Working Group</workgroup>
    <keyword>RSVP-TE</keyword>
    <keyword>GMPLS</keyword>
    <keyword>MPLS</keyword>
    <keyword>MPLS-TP</keyword>

    <abstract>
      <t>This specification describes the configuration of pro-active MPLS-TP
      Operations, Administration, and Maintenance (OAM) Functions for a given
      LSP using a set of TLVs that can be carried in the RSVP-TE protocol.</t>
    </abstract>
  </front>

  <middle>
    <section title="Introduction">
      
      <t>This document describes the configuration of pro-active MPLS-TP
      Operations, Administration, and Maintenance (OAM) Functions for a given
      LSP using a common set of TLVs carried on RSVP-TE [RFC3209].  In
      particular it specifies the mechanisms necessary to establish MPLS-TP OAM
      entities monitoring an LSP and defines information elements and procedures
      to configure pro-active MPLS OAM functions.  Initialization and control of
      on-demand MPLS OAM functions are expected to be carried out by directly
      accessing network nodes via a management interface; hence configuration
      and control of on-demand OAM functions are out-of-scope for this
      document.</t>

      <t>Pro-active MPLS OAM is based on the Bidirectional Forwarding Detection
      (BFD) protocol [RFC5880].  Bidirectional Forwarding Detection (BFD), as
      described in [RFC5880], 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 and detect data plane failures of MPLS-TP point-to-point and
      might also be extended to p2mp connections.</t>

      <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.  [RFC5860] defines the requirements for the
      OAM functionality of MPLS-TP.</t>

      <t>BFD has been chosen to be the basis of pro-active MPLS-TP OAM
      functions.  MPLS-TP OAM extensions for transport applications, for which
      this document specifies the configuration, are specified in [BFD-CCCV],
      [MPLS-PM], and [MPLS-FMS].</t>
      
      <section title="Contributing Authors"> 
	<t>This document is the result of a large team of authors and
	contributors.  The following is a list of the co-authors:</t>

	<t>
	  <list>
	    <t>John Drake</t>
	    <t>Benoit Tremblay</t>
	  </list>
	</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="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
	systems 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 to support bidirectional paths (co-routed or
	bidirectional or associated bidirectional).</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. However, in
	some cases one may want to configure these timers manually, in those
	cases the TLVs defined in this document can be used. </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-CCCV], the BFD tool needs to be extended for
	the proactive CV functionality by the addition of an unique identifier
	in order to meet the requirements.  The document in [BFD-CCCV] 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 [RFC5860].</t>
      </section>
    </section>


    
    <section title="Overview of MPLS OAM for Transport Applications">
      <t>[MPLS-TP-OAM-FWK] describes how MPLS OAM mechanisms are operated to
      meet transport requirements outlined in [RFC5860].</t>
      
      <t>[BFD-CCCV] specifies two BFD operation modes: 1) "CC mode", which uses
      periodic BFD message exchanges with symmetric timer settings, supporting
      Continuity Check, 2) "CV/CC mode" which sends unique maintenance entity
      identifiers in the periodic BFD messages supporting Connectivity
      Verification as well as Continuity Check.</t>
      
      <t>[MPLS-PM] specifies mechanisms for performance monitoring of LSPs, in
      particular it specifies loss and delay measurement OAM functions.</t>
      
      <t>[MPLS-FMS] specifies fault management signals with which a server LSP
      can notify client LSPs about various fault conditions to suppress alarms
      or to be used as triggers for actions in the client LSPs.  The following
      signals are defined: Alarm Indication Signal (AIS), Link Down Indication
      (LDI) and Locked Report (LKR). To indicate client faults associated with
      the attachment circuits Client Signal Failure Indication (CSF) can be
      used. CSF is described in [MPLS-TP-OAM-FWK] and in the context of this
      document is for further study.</t>

      <t>[MPLS-TP-OAM-FWK] describes the mapping of fault conditions to
      consequent actions. Some of these mappings may be configured by the
      operator, depending on the application of the LSP. The following defects
      are identified: Loss Of Continuity (LOC), Misconnectivity, MEP
      Misconfiguration and Period Misconfiguration. Out of these defect
      conditions, the following consequent actions may be configurable: 1)
      whether or not the LOC defect should result in blocking the outgoing data
      traffic; 2) whether or not the "Period Misconfiguration defect" should
      result a signal fail condition.</t>
    </section>

    <section title="Theory of Operations">
      <section title="MPLS OAM Configuration Operation Overview">

	<t>RSVP-TE, or in alternative LSP Ping [LSP-PING CONF], can be used to
	simply establish (i.e., bootstrap) a BFD session or it can selectively
	enable and configure all pro-active MPLS OAM functions.  For this
	specification, BFD MUST be run in asynchronous mode and both sides
	should be in active mode.</t>

	<t>In the simplest scenario RSVP-TE, or in alternative LSP Ping
	[LSP-PING CONF], is used only to bootstrap the BFD session.  In this
	case the initiating node includes an "OAM Configuration TLV" in the
	message it sends to the receiving node at the other end of the LSP. The
	OAM Type in the "OAM Configuration TLV" is set to "MPLS OAM", the CC OAM
	Function flag is set, and a "BFD Configuration sub-TLV" is included.
	The sub-TLV carries a "Local Discriminator sub-TLV" with the
	discriminator value selected by the initiating node for the BFD session
	associated with the LSP. The N flag in the "BFD Configuration sub-TLV"
	MUST be set to enable timer negotiation/re-negotiation via BFD Control
	Messages.</t>

	<t>The receiving node MUST use the Local Discriminator value it receives
	to identify the remote end of the BFD session.  The receiving node must
	send a message to the initiating node that includes an "OAM
	Configuration TLV" containing the same values as it received, except for
	the "Local Discriminator sub-TLV", which contains the local
	discriminator value selected by the receiving node for the BFD
	session.</t>

	<t>Timer negotiation is performed in subsequent BFD control messages.
	This operation is similar to LSP Ping based bootstrapping described in
	[RFC5884].</t>

	<t>If timer negotiation is to be done using the TLVs defined in this
	document rather than with BFD Control packets, the N flag MUST be
	cleared and a "Timer Negotiation Parameters sub-TLV" MUST be present in
	the "BFD Configuration sub-TLV".  In this case, there are two
	configuration options, symmetric and asymmetric.  If symmetric
	configuration is used, the S flag in "BFD Configuration sub-TLV" MUST be
	set.  If the flag is cleared, the configuration is completed
	asymmetrically in the two directions.  Section 3.3.2 includes a detailed
	explanation of such configuration.</t>

	<t>In the case of the "CV/CC mode" OAM [BFD-CCCV], the "CV" flag MUST be
	set in addition to the CC flag in the "OAM Configuration TLV".  The
	information required to support this functionality is defined in
	[MPLS-TP-IDENTIF]. If RSVP-TE is used, this information is found
	respectively in the SESSION and SENDER_TEMPLATE object with no need of
	additional sub-TLVs as described in section 3.2.
	</t>

	<t>When BFD Control packets are transported in the G-ACh they are not
	protected by any end-to-end checksum, only lower-layers are
	providing error detection/correction. A single bit error, e.g. a flipped
	bit in the BFD State field could cause the receiving end to wrongly
	conclude that the link is down and thus trigger protection switching. To
	prevent this from happening the "BFD Configuration sub-TLV" has an
	Integrity flag that when set enables BFD Authentication using Keyed SHA1
	with an empty key (all 0s) [RFC5880]. This would make every BFD Control
	packet carry an SHA1 hash of itself that can be used to detect errors.</t>

	<t>If BFD Authentication using a shared key / password is desired
	(i.e. actual authentication not only error detection) the "BFD
	Authentication sub-TLV" MUST be included in the "BFD Configuration
	sub-TLV". The "BFD Authentication sub-TLV" is used to specify which
	authentication method that should be used and which shared key /
	password that should be used for this particular session. How the key
	exchange is performed is out of scope of this document.</t>

	<t>Additional OAM functions may be configured by setting the appropriate
	flags in the "OAM Functions TLV", these include Performance Measurements
	(packet loss and packet delay) and Fault Management Signal handling.</t>

	<t>By setting the PM Loss flag in the "OAM Functions TLV" and including
	the "MPLS OAM PM Loss sub-TLV" one can configure the measurement
	interval and loss threshold values for triggering protection.</t>

	<t>Delay measurements are configured by setting PM Delay flag in the
	"OAM Functions TLV" and including the "MPLS OAM PM Loss sub-TLV" one can
	configure the measurement interval and the delay threshold values for
	triggering protection.</t>
	<t>To configure Fault Monitoring Signals and their refresh time the FMS
	flag in the "OAM Functions TLV" MUST be set and the "MPLS OAM FMS
	sub-TLV" included. </t>
	<!-- Add more description about the loss delay and especially FMS things -->
      </section>

      <section title="OAM Configuration TLV">
        <t>The "OAM Configuration TLV" is depicted in the following figure.  It
        specifies the OAM functions that are to be used for the subject LSP and
        it is defined in [OAM-CONF-FWK]. The "OAM Configuration
        TLV" is carried in the LSP_ATTRIBUTES object in Path and Resv
        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                       |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
~                           sub-TLVs                            ~
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                
]]>
	    </artwork>                                             
	  </figure>                                                                                                  
	</t>
	
	<t>Type: indicates the "OAM Configuration TLV" (2) (IANA to assign).</t>
	
	<t>OAM Type: one octet 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>This document defines a new OAM Type: "MPLS OAM" (suggested value 2,
	IANA to assign) from the "RSVP-TE OAM Configuration Registry".  The
	"MPLS OAM" type is set to request the establishment of OAM functions for
	MPLS-TP LSPs.  The specific OAM functions are specified in the "Function
	Flags" sub-TLV as depicted in [OAM-CONF-FWK].</t>

	<t>The receiving edge LSR when the MPLS-TP OAM Type is requested should
	check which OAM Function Flags are set in the "Function Flags TLV" and
	look for the corresponding technology specific configuration TLV.</t>

	<t>Additional corresponding sub-TLVs are as follows:</t>

	<t><list>
	    <t>- "BFD Configuration sub-TLV", which MUST be included if the CC
	    OAM Function flag is set. This sub-TLV MUST carry a "BFD Local
	    Discriminator sub-TLV" and a "Timer Negotiation Parameters sub-TLV"
	    if the N flag is cleared. It MAY carry a "BFD Authentication
	    sub-TLV" if the I flag is set. If the I flag is set but no "BFD
	    Authentication sub-TLV" is included Keyed SHA1 with an empty key is
	    used.</t>

	    <t>- "MPLS OAM PM Loss sub-TLV", which MAY be included if the
	    PM/Loss OAM Function flag is set. If the "MPLS OAM PM Loss sub-TLV"
	    is not included, default configuration values are used.</t>

	    <t>- "MPLS OAM PM Delay sub-TLV", which MAY be included if the
	    PM/Delay OAM Function flag is set. If the "MPLS OAM PM Delay
	    sub-TLV" is not included, default configuration values are used.</t>

	    <t>- "MPLS OAM FMS sub-TLV", which MAY be included if the FMS OAM
	    Function flag is set. If the "MPLS OAM FMS sub-TLV" is not included,
	    default configuration values are used.</t>

	    
	    <!-- Commented since we're trying to divorce the two documents -->
	    <!-- <t>- Moreover, "Unique MEP-ID of Source", MUST be included in
	    case the configuration is done with LSP Ping -->
	    <!-- and CV flag is set as defined in [LSP-PING CONF]. But this is outside the scope of this document.</t> -->

	</list></t>

	<t>Moreover, if the CV flag is set, the CC flag MUST be set at the same
	time. The format of an MPLS-TP CV/CC message is shown in [BFD-CCCV] and
	it requires, together with the BFD control packet information, the
	"Unique MEP-ID of source of BFD packet".  [MPLS-TP-IDENTIF] defines the
	composition of such identifier as:</t>

	<t><"Unique MEP-ID of source of BFD packet"> ::=
	<src_node_id><src_tunnel_num><lsp_num></t>

	<!-- 
	   <t>
             <figure>
               <artwork><![CDATA[
  
                 <"Unique MEP-ID of source of BFD packet"> ::= <src_node_id><src_tunnel_num><lsp_num>
			  
             ]]></artwork>                                             
	     </figure>                                                                                                  
	   </t>
	   -->
	
	<t>GMPLS signaling [RFC3473] uses a 5-tuple to uniquely identify an LSP
	within an operator's network.  This tuple is composed of a Tunnel
	Endpoint Address, Tunnel_ID, Extended Tunnel ID, and Tunnel Sender
	Address and (GMPLS) LSP_ID.</t>

	<t>Hence, the following mapping is used without the need of redefining a
	new TLV for MPLS-TP proactive CV purpose.</t>

	<t>
	  <list>
	    <t>- Tunnel ID = src_tunnel_num</t>
	    <t>- Tunnel Sender Address = src_node_id</t>
	    <t>- LSP ID = LSP_Num</t>
	  </list>
	</t>

	<t>"Tunnel ID" and "Tunnel Sender Address" are included in the "SESSION"
	object [RFC3209], which is mandatory in both Path and Resv messages.</t>

	<t>"LSP ID" will be the same on both directions and it is included in
	the "SENDER_TEMPLATE" object [RFC3209] which is mandatory in Path
	messages.</t>

	<!-- Commented since we're trying to divorce the two documents -->
	<!-- <t>In case the configuration is done via LSP Ping [LSP-PING CONF]
	the "Unique MEP-ID of Source" is needed to -->
	<!-- supply this information but this is defined in [LSP-PING CONF] and it is outside the scope of this document.</t> -->

	<t>[Author's note: the same "Unique MEP-ID of source" will be likely
	required for Performance monitoring purposes.  However for the moment in
	[MPLS-PM] it is stated: "The question of ACH TLV usage and the manner of
	supporting metadata such as authentication keys and node identifiers is
	deliberately omitted.  These issues will be addressed in a future
	version of the document."]</t>

      </section>

      <section title="BFD Configuration sub-TLV">
	<t>The "BFD Configuration sub-TLV" (depicted below) is defined for BFD OAM
	specific configuration parameters.  The "BFD Configuration sub-TLV" is
	carried as a sub-TLV of the "OAM Configuration TLV".</t>

	<t>This 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 (3) (IANA)     |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Vers.| PHB |N|S|I|    Reserved (set to all 0s)                 |      
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                           sub-TLVs                            ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                  			  
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>

	<t>Type: indicates a new type, the "BFD Configuration sub-TLV" (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>PHB: Identifies the Per-Hop Behavior (PHB) to be used for periodic
	continuity monitoring messages.</t>

	<t>BFD Negotiation (N): If set timer negotiation/re-negotiation via BFD
	Control Messages is enabled, when cleared it is disabled.</t>

	<t>Symmetric session (S): If set the BFD session MUST use symmetric
	timing values. </t>
	<!-- added description of the (S) flag --> 
	<t>Integrity (I): If set BFD Authentication MUST be enabled. If the "BFD
	Configuration sub-TLV" does not include a "BFD Authentication sub-TLV" the
	authentication MUST use Keyed SHA1 with an empty pre-shared key (all
	0s). </t>

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

	<t><list>
	    <t>- "Local Discriminator sub-TLV";</t>

	    <t>- "Negotiation Timer Parameters sub-TLV" if N flag is
	    cleared.</t>
	</list></t>

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

	<t><list>
	    <t>- "Local Discriminator sub-TLV;"</t>

	    <t>- "Negotiation Timer Parameters sub-TLV" if:
	      <list>
		<t>- N flag and S are cleared </t>
		<t>- N flag is cleared and S flag is set and a timing value
		higher than the one received needs to be used</t>
	      </list>
	    </t>
	</list></t>
	
	<t>Reserved: Reserved for future specification and set to 0.</t>
	
	<section title="Local Discriminator sub-TLV">

	  <t>The "Local Discriminator sub-TLV" is carried as a sub-TLV of the
	  "BFD Configuration sub-TLV" and 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 = 8            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    		  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 TLV total length in octets.</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.</t>
          
	</section>

	<section title="Negotiation Timer Parameters sub-TLV">
	  <t>The "Negotiation Timer Parameters sub-TLV" is carried as a sub-TLV
	  of the "BFD Configuration sub-TLV" and 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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |  Timer Neg. Type (2) (IANA)   |          Length = 20          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Acceptable Min. Asynchronous TX interval              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Acceptable Min. Asynchronous RX interval              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |               Required Echo TX Interval                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |  Detect. Mult.|           Reserved  (set to all 0s)           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             ]]></artwork>                                             
	    </figure>
	  </t>

	  <t>Type: indicates a new type, the "Negotiation Timer Parameters
	    sub-TLV" (IANA to define).</t>

	  <t>Length: indicates the TLV total length in octets. (20)</t>

	  <t>Acceptable Min. Asynchronous TX interval: in case of S (symmetric)
	  flag set in the "BFD Configuration sub-TLV", it expresses the desired time
	  interval (in microseconds) at which the LER initiating the signaling
	  intends to both transmit and receive BFD periodic control packets. If
	  the receiving edge LSR can not support such value, it is allowed to
	  reply back with an interval greater than the one proposed.</t>

	  <t>In case of S (symmetric) flag cleared in the "BFD Configuration
	  sub-TLV", this field expresses the desired time interval (in
	  microseconds) at which a edge LSR intends to transmit BFD periodic
	  control packets in its transmitting direction.</t>

	  <t>Acceptable Min. Asynchronous RX interval: in case of S (symmetric)
	  flag set in the "BFD Configuration sub-TLV", this field MUST be equal to
	  "Acceptable Min. Asynchronous TX interval" and has no additional
	  meaning respect to the one described for "Acceptable Min. Asynchronous
	  TX interval".</t>

	  <t>In case of S (symmetric) flag cleared in the "BFD Configuration
	  sub-TLV", it expresses the minimum time interval (in microseconds) at
	  which edge LSRs can receive BFD periodic control packets. In case this
	  value is greater than the "Acceptable Min. Asynchronous TX interval"
	  received from the other edge LSR, such edge LSR MUST adopt the
	  interval expressed in this "Acceptable Min. Asynchronous RX
	  interval".</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
	  [RFC5880] 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>

	  <t>Detection time multiplier: The negotiated transmit interval,
	  multiplied by this value, provides the Detection Time for the
	  receiving system in Asynchronous mode.</t>
	  <t>Reserved: Reserved for future specification and set to 0.</t>
	</section>

	<section title="BFD Authentication sub-TLV">
	  <t>The "BFD Authentication sub-TLV" is carried as a sub-TLV of the
	  "BFD Configuration sub-TLV" and 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|    BFD Auth. Type (3) (IANA)  |          Length = 8           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|   Auth Type   |  Auth Key ID  |         Reserved (0s)         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             ]]></artwork>                                             
	    </figure>
	  </t>
	  <t>Type: indicates a new type, the "BFD Authentication sub-TLV" (IANA to define).</t>
	  <t>Length: indicates the TLV total length in octets. (8)</t>
	  <t>Auth Type: indicates which type of authentication to use. The
	    same values as are defined in section 4.1 of [RFC5880] are
	    used. </t>
	  <t>Auth Key ID: indicates which authentication key or password
	    (depending on Auth Type) should be used. How the key exchange is
	    performed is out of scope of this document.</t>
	  <t>Reserved: Reserved for future specification and set to 0. </t>
	</section>
      </section>
     
      <section title="MPLS OAM PM Loss sub-TLV">
	<t>The "MPLS OAM PM Loss sub-TLV" depicted below is carried as a sub-TLV of
	the "OAM Configuration sub-TLV".</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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |  PM Loss Type (3) (IANA)      |          Length = 16          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |Vers.|E|C|     |           Reserved (set to all 0s)      | PHB |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Measurement Interval                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Loss Threshold                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
]]></artwork>                                             
	  </figure>                                                                                                  
	</t>
	
	<t>Type: indicates a new type, the "MPLS OAM PM Loss" (IANA to define).</t>
	
	<t>Length: indicates the TLV total length in octets.</t>
	
	<t>Version: indicates the Loss measurement protocol version.</t>
	
	<t>Configuration Flags:
	  <list>
	    <t>- E: exclude from the Loss Measurement all G-ACh messages</t>
	    <t>- C: require the use of a counter in the "Querier Context" field
	    described in [MPLS-PM]</t>
	    <t>- Remaining bits: Reserved for future specification and set to
	    0.</t>
	  </list>
	</t>

	<t>PHB: identifies the per-hop behavior of packets with loss
	information.</t>

	<t>Measurement Interval: the time interval (in microseconds) at which
	Loss Measurement query messages MUST be sent on both directions. If the
	edge LSR receiving the Path message can not support such value, it can
	reply back with a higher interval.</t>

	<t>Loss Threshold: the threshold value of lost packets over which
	protections MUST be triggered.</t>
      </section>	

      <section title="MPLS OAM PM Delay sub-TLV">
	<t>The "MPLS OAM PM Delay sub-TLV" depicted below is carried as a sub-TLV of
	the "OAM Configuration sub-TLV".</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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |  PM Delay Type (4) (IANA)     |          Length = 16          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |Vers.| Flags   |           Reserved  (set to all 0s)     | PHB |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Measurement Interval                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Delay Threshold                          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>

	<t>Type: indicates a new type, the "MPLS OAM PM Delay" (IANA to define).</t>

	<t>Length: indicates the TLV total length in octets.</t>

	<t>Version: indicates the Delay measurement protocol version.</t>

	<t>Configuration Flags:
	  <list>
	    <t>- E: exclude from the Loss Measurement all G-ACh messages</t>
	    <t>- C: require the use of a counter in the "Querier Context" field
	    described in [MPLS-PM]</t>
	    <t>- Remaining bits: Reserved for future specification and set to
	    0.</t>
	  </list>
	</t>

	<t>PHB: - identifies the per-hop behavior of packets with delay
	information.</t>

	<t>Measurement Interval: the time interval (in microseconds) at which
	Delay Measurement query messages MUST be sent on both directions. If the
	edge LSR receiving the Path message can not support such value, it can
	reply back with a higher interval.</t>

	<t>Delay Threshold: the threshold value of measured delay (in
	microseconds) over which protections MUST be triggered.</t>

	<t>[Author's note: TBD if we want to include the timestamp format
	negotiation as in [MPLS-PM] 4.2.5.]</t>

      </section>

      <section title="MPLS OAM FMS sub-TLV">
	<t>The "MPLS OAM FMS sub-TLV" depicted below is carried as a sub-TLV of the
	  "OAM Configuration sub-TLV".</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 (5)  (IANA)    |        Length = 12            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |A|D|L|C|             Reserved   (set all to 0s)        |E| PHB |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      Refresh Timer                            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             ]]></artwork>                                             
	  </figure>                                                                                                  
	</t>

	<t>Type: indicates a new type, the "MPLS OAM FMS" (IANA to define).</t>

	<t>Length: indicates the TLV total length in octets.</t>

	<t>Signal Flags: are used to enable the following signals:
	  <list>
	    <t>- A: Alarm Indication Signal (AIS) as described in [MPLS-FMS]</t>
	    <t>- D: Link Down Indication (LDI) as described in [MPLS-FMS]</t>
	    <t>- L: Locked Report (LKR) as described in [MPLS-FMS]</t>
	    <t>- C: Client Signal Failure (CSF) as described in [MPLS-CSF]</t>
	    <t>- Remaining bits: Reserved for future specification and set to
	    0.</t>
	  </list>
	</t>

	<t>Configuration Flags:
	  <list>
	    <t>- E: used to enable/disable explicitly clearing faults</t>
	    <t>- PHB: identifies the per-hop behavior of packets with fault
	    management information</t>
	  </list>
	</t>
	<t>Refresh Timer: indicates the refresh timer (in microseconds) of fault
	indication messages. If the edge LSR receiving the Path message can not
	support such value, it can reply back with a higher interval.</t>

      </section>
    </section>

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

    <section anchor="IANA" title="IANA Considerations">
      
      <t>This document specifies the following new TLV types:</t>
      <t>
	<list>
	  <t>- "BFD Configuration" type: 2;</t>
	  <t>- "MPLS OAM PM Loss" type: 3;</t>
	  <t>- "MPLS OAM PM Delay" type: 4;</t>
	  <t>- "MPLS OAM FMS" type: 5.</t>
	</list> 
      </t>
      
      <t>sub-TLV types to be carried in the "BFD Configuration sub-TLV":
	<list>
	  <t>- "Local Discriminator" sub-TLV type: 1;</t>
	  <t>- "Negotiation Timer Parameters" sub-TLV type: 2.</t>
	  <t>- "BFD Authentication" 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>- "MPLS OAM Unsupported Functionality";</t>
	  <t>- "OAM Problem/Unsupported TX rate interval".</t>
	</list>
      </t>

    </section>

    <section title="Acknowledgements">
      <t>The authors would like to thank David Allan, Lou Berger, Annamaria
      Fulignoli, Eric Gray, Andras Kern, David Jocha and David Sinicrope for
      their useful comments.</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.5654"?>
      <?rfc include="reference.RFC.5880"?>
      <?rfc include="reference.RFC.3209"?>
      <?rfc include="reference.RFC.3473"?>
      <?rfc include="reference.RFC.5884"?>
      <?rfc include="reference.RFC.5860"?>

      <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="MPLS-TP-IDENTIF"
		 target="draft-ietf-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>
	  
	  <author initials="E" surname="Gray">
            <organization></organization>
          </author>

          <date year="2010" />
        </front>
      </reference>

      <reference anchor="MPLS-PM"
		 target="draft-ietf-mpls-tp-loss-delay">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>Packet Loss and Delay Measurement for the MPLS Transport Profile</title>

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

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

          <date year="2010" />
        </front>
      </reference>
      
      <reference anchor="MPLS-PM-Profile"
		 target="draft-ietf-mpls-tp-loss-delay-profile">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>A Packet Loss and Delay Measurement Profile for MPLS-based Transport Networks</title>
          <author initials="S" surname="Bryant">
            <organization></organization>
          </author>
          <author initials="D" surname="Frost">
            <organization></organization>
          </author>
          <date year="2010" />
        </front>
      </reference>

      <reference anchor="MPLS-FMS"
		 target="draft-ietf-mpls-tp-fault">
        <!-- the following is the minimum to make xml2rfc happy -->
	
        <front>
          <title>MPLS Fault Management OAM</title>
	  
          <author initials="G" surname="Swallow">
            <organization></organization>
          </author>
	  
          <author initials="A" surname="Fulignoli">
            <organization></organization>
          </author>
	  
          <author initials="M" surname="Vigoureux">
            <organization></organization>
          </author>
	  
	  <author initials="S" surname="Boutros">
            <organization></organization>
          </author>
	  
	  <author initials="D" surname="Ward">
            <organization></organization>
          </author>
	  
          <date year="2009" />
        </front>
      </reference>

      <reference anchor="MPLS-CSF"
		 target="draft-he-mpls-tp-csf">
	<!-- the following is the minimum to make xml2rfc happy -->
	
	<front>
	  <title>Indication of Client Failure in MPLS-TP</title>
	  
	  <author initials="J" surname="He">
	    <organization></organization>
	  </author>
	  
	  <author initials="H" surname="Li">
	    <organization></organization>
	  </author>
	  
	  <author initials="E" surname="Bellagamba">
	    <organization></organization>
	  </author>
	  
	  <date year="2010" />
	</front>
      </reference>
      
    </references>

    <references title="Informative References">

      <reference anchor="LSP-PING CONF"
		 target="draft-ietf-mpls-lsp-ping-mpls-tp-oam-conf">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>Configuration of pro-active MPLS-TP Operations, Administration, and Maintenance (OAM) Functions Using LSP Ping</title>

          <author initials="E" surname="Bellagamba">
            <organization>Ericsson</organization>
          </author>

          <author initials="L" surname="Andersson">
            <organization>Ericsson</organization>
          </author>

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

          <author initials="P" surname="Skoldstrom">
            <organization>Acreo</organization>
          </author>

          <date year="2010" />
        </front>
      </reference>

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

        <front>
          <title>Proactive Connectivity Verification, Continuity Check and Remote Defect indication for MPLS Transport Profile</title>

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

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

          <author initials="J" surname="Drake">
            <organization></organization>
          </author>

          <date year="2010" />
        </front>
      </reference>

      <reference anchor="BFD-Ping"
		 target="draft-ietf-mpls-tp-lsp-ping-bfd-procedures-02">
        <!-- the following is the minimum to make xml2rfc happy -->

        <front>
          <title>LSP Ping and BFD encapsulation over ACH</title>

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

          <author initials="R" surname="Aggarwal">
            <organization></organization>
          </author>

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

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

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

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

          <date year="2010" />
        </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>Operations, Administration and Maintenance Framework for MPLS-based Transport Networks</title>

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

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

          <date year="2010" />
        </front>
      </reference>

      <?rfc include="reference.RFC.4447"?>
      <?rfc include="reference.RFC.5921"?>

      <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-ietf-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="Y" surname="Weingarten">
            <organization></organization>
          </author>
	  
	  <author initials="E" surname="Bellagamba">
            <organization></organization>
          </author>

          <date year="2011" />
        </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 12:11:07