One document matched: draft-nitinb-mpls-tp-lsp-ping-bfd-procedures-00.txt




Network Working Group                                    N. Bahadur, Ed.
Internet-Draft                                               R. Aggarwal
Intended status: Standards Track                  Juniper Networks, Inc.
Expires: January 6, 2010                                       T. Nadeau
                                                                      BT
                                                             N. Sprecher
                                                           Y. Weingarten
                                                  Nokia Siemens Networks
                                                            July 5, 2009


                      LSP-Ping and BFD for MPLS-TP
            draft-nitinb-mpls-tp-lsp-ping-bfd-procedures-00

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Abstract

   LSP-Ping and BFD for MPLS are existing and widely deployment OAM
   mechanisms for MPLS LSPs.  This document describes how LSP-Ping and
   BFD for MPLS can be used to perform OAM on MPLS-TP LSPs.  This
   document describes extensions to LSP-Ping when IP addressing is not
   in use, in a MPLS-TP deployment scenario.  These extensions are also
   meant to be applicable when it is desirable to avoid the use of IP
   encapsulation for exchanging LSP-Ping OAM messages.  This document
   also clarifies the use of BFD for MPLS-TP LSPs when IP addressing may
   not be available and/or it may not be desirable to encapsulate BFD
   packets in IP.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1.  Conventions used in this document  . . . . . . . . . . . .  4
     1.2.  Existing LSP-Ping and BFD for MPLS LSPs Encapsulation
           Mechanism  . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.3.  Non-IP LSP-Ping and BFD for MPLS LSPs Encapsulation
           Mechanism  . . . . . . . . . . . . . . . . . . . . . . . .  5
   2.  LSP-Ping extensions  . . . . . . . . . . . . . . . . . . . . .  5
     2.1.  LSP-Ping packet over ACH . . . . . . . . . . . . . . . . .  5
     2.2.  LSP-Ping packet over PW-ACH  . . . . . . . . . . . . . . .  6
     2.3.  New address type for Downstream Mapping TLV  . . . . . . .  6
     2.4.  Source Address TLV . . . . . . . . . . . . . . . . . . . .  6
     2.5.  Destination Address TLV  . . . . . . . . . . . . . . . . .  7
   3.  Performing LSP-Ping over MPLS-TP LSPs  . . . . . . . . . . . .  7
     3.1.  Traditional LSP-Ping . . . . . . . . . . . . . . . . . . .  7
     3.2.  Non-IP based LSP-Ping  . . . . . . . . . . . . . . . . . .  8
     3.3.  P2MP Considerations  . . . . . . . . . . . . . . . . . . .  9
   4.  Performing LSP Traceroute over MPLS-TP LSPs  . . . . . . . . .  9
     4.1.  Traditional LSP Traceroute . . . . . . . . . . . . . . . . 10
     4.2.  Non-IP based LSP Traceroute  . . . . . . . . . . . . . . . 10
       4.2.1.  Ingress node procedure for sending echo request
               packets  . . . . . . . . . . . . . . . . . . . . . . . 10
       4.2.2.  Ingress node procedure for receiving echo response
               packets  . . . . . . . . . . . . . . . . . . . . . . . 10
       4.2.3.  Transit and egress node procedure  . . . . . . . . . . 10
     4.3.  P2MP Considerations  . . . . . . . . . . . . . . . . . . . 11
     4.4.  ECMP Considerations  . . . . . . . . . . . . . . . . . . . 11
   5.  Running BFD over MPLS-TP LSPs  . . . . . . . . . . . . . . . . 11
   6.  Applicability  . . . . . . . . . . . . . . . . . . . . . . . . 12
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 12
   8.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 12
     8.1.  New ACH Channel Type . . . . . . . . . . . . . . . . . . . 12
     8.2.  New LSP-Ping TLV Types . . . . . . . . . . . . . . . . . . 13



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   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 13
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 13
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14















































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1.  Introduction

   LSP-Ping [RFC4379] and [I-D.ietf-bfd-mpls] are OAM mechanisms for
   MPLS LSPs.  This document describes how LSP-Ping and BFD for MPLS can
   be used to perform OAM on MPLS-TP LSPs.  The document considers two
   cases.  The first is when IP addressing and host stack are available
   on egress and transit LSRs.  The second is when such capabilities are
   either not available or it is not desirable to use them.

   Sections Section 3.2 and Section 4.2 describes the theory of
   operation for performing LSP-Ping over MPLS-TP LSPs.  Section
   Section 2.1 describes the new TLVs and LSP-Ping extensions for
   performing LSP-Ping in the absence of IP addressing.

1.1.  Conventions used in this document

   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 [RFC2119].

1.2.  Existing LSP-Ping and BFD for MPLS LSPs Encapsulation Mechanism

   LSP-Ping requires IP addressing on the egress and transit LSRs for
   performing OAM on MPLS signaled LSPs and pseudowires.  BFD for MPLS
   LSPs also requires IP addressing.  In particular, in these cases the
   LSP-Ping and BFD packets generated by an ingress LSR are encapsulated
   in an IP/UDP header with the destination address from the 127/8 range
   and then encapsulated in the MPLS label stack ([RFC4379] ,
   [I-D.ietf-bfd-mpls]).  Egress LSRs use the presence of the 127/8
   destination address to identify the OAM packets and rely further on
   the UDP port number to determine whether the packet is a LSP-Ping or
   a BFD packet.  It is to be noted that this determination does not
   require IP forwarding capabilities.  It requires the presence of an
   IP host stack which enables egress LSRs to process packets with a
   destination address from the 127/8 range.  [RFC1122] allocates the
   127/8 range as "Internal host loopback address" and [RFC1812] states
   that "a router SHOULD NOT forward, except over a loopback interface,
   any packet that has a destination address on network 127".

   LSP-Ping and BFD for MPLS specify procedures that allow an egress LSR
   to use a MPLS LSP for forwarding LSP-Ping or BFD packets to the
   ingress LSR.  This ensures that IP forwarding capabilities are not
   required and meets the MPLS-TP requirement of not having IP
   forwarding capabilities.

   [I-D.ietf-mpls-tp-framework] specifies that IP addressing is the
   default addressing mechanism for MPLS-TP networks.  An IP host stack
   must be present when IP addressing is in use.  This implies that



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   exisiting LSP-Ping and BFD procedures can be used as is in MPLS-TP
   environments when IP addressing is in use.

1.3.  Non-IP LSP-Ping and BFD for MPLS LSPs Encapsulation Mechanism

   In certain MPLS-TP deployment scenarios IP addressing might not be
   available or it may be preferred to use non-IP encapsulation for LSP-
   Ping and BFD packets.  To enable re-use of OAM techniques provided by
   LSP-Ping and BFD in such networks, rest of this document defines
   extensions to LSP-Ping and procedures for using BFD.  The document
   defines a new code-point for using LSP-Ping with an ACH header.
   Further, it describes how LSP-Ping can be used to perform
   Connectivity Verification, Route Tracing and Adjacency functions
   specified in [I-D.ietf-mpls-tp-oam-requirements].  This document also
   clarifies the usage of BFD in the context of MPLS-TP LSPs.

   Sections Section 3.2 and Section 4.2 describe the theory of operation
   for performing LSP-Ping over MPLS-TP LSPs with a non-IP
   encapsulation.  Section 2.1 describes the new TLVs and LSP-Ping
   extensions for performing LSP-Ping in the absence of IP addressing.
   Section 5 describes procedures for using BFD with non-IP
   encapsulation."


2.  LSP-Ping extensions

2.1.  LSP-Ping packet over ACH

   [RFC5586] defines an ACH mechanism for MPLS LSPs.  This document
   defines a new ACH channel type for when IP addressing is not in use
   for LSP-Ping over associated bi-directional LSPs and co-routed bi-
   directional LSPs.

   ACH TLVs CANNOT be associated with LSP-Ping channel type.

       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 2
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |0 0 0 1|Version|   Reserved    |     LSP-Ping Channel Type     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                    Figure 1: LSP-Ping ACH Channel Type








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2.2.  LSP-Ping packet over PW-ACH

   [RFC4385] defines an PW-ACH mechanism for pseudowires.  The ACH
   channel type for LSP-Ping defined in Section 2.1 will be re-used for
   pseudowires so that IP addressing is not needed when using LSP-Ping
   OAM over pseudowires.

2.3.  New address type for Downstream Mapping TLV

   [RFC4379] defines the Downstream Mapping TLV.  A new type is being
   added to the Address Type field as follows:

         Type #        Address Type           K Octets
         ------        --------------         --------
             0         Not Applicable                8


             Figure 2: Downstream Mapping TLV new Address Type

   The new address type indicates that no address is present in the
   Downstream Mapping TLV.  Multipath type MAY be set to 0 (no mutlpath)
   when using this address type.

   When this address type is used, on receipt of a lsp-ping echo
   request, both interface verification and label stack validation MUST
   be bypassed.

   The new address type is also applicable to the Detailed Downstream
   Mapping TLV defined in [I-D.ietf-mpls-lsp-ping-enhanced-dsmap].

2.4.  Source Address TLV

   A new optional TLV is being defined for encapsulating the source
   address.  The optional TLV will be part of the TLVs defined in
   [RFC4379].  Only 1 source address TLV MUST be present in a LSP-Ping
   packet.  The source address MUST specify the address of the
   originator of the packet.  If more than 1 such TLV is present in a
   LSP-Ping request packet, then an error of "Malformed echo request
   received" SHOULD be returned.  If more than 1 source address TLV is
   present in a LSP-Ping response packet, then the packet SHOULD be
   dropped without further processing.  The source address TLV MUST NOT
   be used if IP addressing is in use.  If IP addressing is in use, then
   one should use lsp-ping with IP.

   The format of the TLV is TBD.






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2.5.  Destination Address TLV

   A new optional TLV is being defined for encapsulating the destination
   address.  The optional TLV will be part of the TLVs defined in
   [RFC4379].  One or more of this TLV MAY be included in a LSP-Ping
   request message.  If more than 1 destination address TLV is present
   in a LSP-Ping response packet, then the packet SHOULD be dropped
   without further processing.  The destination address MUST specify the
   intended receipient(s) of the packet.  If the destination address
   specified in any of the Destination Address TLVs does not match any
   address associated with the node which receives the LSP-Ping packet,
   then the LSP-Ping packet SHOULD be dropped without further
   processing.  The destination address TLV MUST NOT be used if IP
   addressing is in use.  If IP addressing is in use, then one should
   use lsp-ping with IP.

   The format of the TLV is TBD.


3.  Performing LSP-Ping over MPLS-TP LSPs

   This section specifies how LSP-Ping ping can be used in the context
   of MPLS-TP LSPs.  The LSP-Ping ping function meets the Connectivity
   Verification requirement specified in
   [I-D.ietf-mpls-tp-oam-requirements].

3.1.  Traditional LSP-Ping

   Traditional LSP-Ping packets ride over the LSP and contain an IP/UDP
   packet within them.  The IP header is not used for forwarding (since
   the LSP is forwarded using MPLS label switching).  The IP header is
   used mainly for addressing and can be used in the context of MPLS-TP
   LSPs.  This form of LSP-Ping OAM MUST be supported for MPLS-TP LSPs
   when IP addressing is in use.  The figure below shows an MPLS-TP LSP-
   Ping OAM packet.
















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       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 2
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         MPLS Label stack                      |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       IP/UDP Headers                          |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      LSP-Ping payload                         |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                         Figure 3: LSP-Ping packet

   The LSP-Ping Reply mode [RFC4379] in the LSP-Ping echo request MUST
   be set to 4 (Reply via application level control channel).

   The LSP-Ping reply message MUST be sent on the reverse path of the
   LSP.  The reply MUST contain IP/UDP headers followed by the LSP-Ping
   payload.  The destination address in the IP header MUST be set to
   that of the sender of the request message.  The source adderss in the
   IP header MUST be set to a valid address of the replying node.

3.2.  Non-IP based LSP-Ping

   The OAM procedures defined in [RFC4379] require the use of IP
   addressing and in some cases IP routing to perform OAM functions.
   When the ACH header is used, IP addressing and routing is not needed.
   This section describes procedures for performing lsp-ping without a
   dependency on IP.

   When ACH header is used, an LSP-Ping packet will look as follows:

















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       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 2
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         MPLS Label stack                      |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                          GAL                                  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |0 0 0 1|Version|   Reserved    |     LSP-Ping Channel Type     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      LSP-Ping payload                         |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                    Figure 4: LSP-Ping packet with ACH

   When using LSP-Ping over the ACH header, the LSP-Ping Reply mode
   [RFC4379] in the LSP-Ping echo request MUST be set to 4 (Reply via
   application level control channel).

   The ingress node MAY attach a Source Address TLV (Section 2.4) to
   identify the node originating the request.

   The LSP-Ping reply message MUST be sent on the reverse path of the
   LSP using ACH.  The LSP-Ping payload MUST directly follow the ACH
   header and no IP and/or UDP headers MUST be attached.  If the request
   message contained the Source Address TLV and a response is being sent
   to the originator, then a Destination Address TLV (Section 2.5)
   SHOULD be added to the reply message.  The contents of the LSP-Ping
   request Source Address TLV should be copied into the LSP-Ping
   response Destination Address TLV.  The responding node MAY attach a
   Source Address TLV to identify the node sending the response.

3.3.  P2MP Considerations

   [I-D.ietf-mpls-p2mp-lsp-ping] describes how LSP-Ping can be used for
   OAM on P2MP LSPs.  The procedures described in this draft apply as is
   irrespective of whether we use the mechanism specified in Section 3.1
   or the mechanism specified in Section 3.2.


4.  Performing LSP Traceroute over MPLS-TP LSPs

   This section specifies how LSP-Ping traceroute can be used in the
   context of MPLS-TP LSPs.  The LSP-Ping traceroute function meets the
   Adjancency and Route Tracing requirement specified in
   [I-D.ietf-mpls-tp-oam-requirements].



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   When performing lsp-ping traceroute, the ingress node inserts a
   Downstream Mapping TLV to get the downstream node information and to
   enable LSP verification along the transit nodes.  The Downstream
   mapping TLV can be used as is for performing the traceroute.  If IP
   addressing is not in use, then the Address Type field in the
   Downstream Mapping TLV can be set to "Not applicable" (Section 2.3).
   The Downstream Mapping TLV address type field can be extended to
   include other address types as need be.

4.1.  Traditional LSP Traceroute

   The mechanics of LSP-Ping traceroute are similar to those described
   for ping in Section 3.1.  Traceroute packets sent by the lsp ingress
   MUST adhere to the format described in Section 3.2.This form of LSP-
   Ping OAM MUST be supported for MPLS-TP LSPs, when IP addressing is in
   use.

4.2.  Non-IP based LSP Traceroute

   This section describes the procedures for performing lsp-traceroute
   when using the ACH header and without any dependency on IP
   addressing.  The procedures specified in Section 3.2 with regards to
   Source Address TLV and Destination Address TLV apply to LSP
   traceroute as well.

4.2.1.  Ingress node procedure for sending echo request packets

   Traceroute packets sent by the lsp ingress MUST adhere to the format
   described in Section 3.2.  MPLS-TTL expiry (as described in
   [RFC4379]) will be used to direct the packets to specific nodes along
   the LSP path.

4.2.2.  Ingress node procedure for receiving echo response packets

   The lsp-ping traceroute responses will be received on the LSP itself
   and the presence of an ACH header with channel type of LSP-Ping is an
   indicator that the packet contains LSP-ping payload.

4.2.3.  Transit and egress node procedure

   When a echo request reaches the transit or egress, the presence of
   the ACH channel type of LSP-Ping will indicate that the packet
   contains LSP-Ping data.  The LSP-Ping data and the label stack should
   be able to identify the LSP associated with the echo request packet.
   In case if there is an error and the node is unable to idenfity the
   LSP on which the echo response should to be sent, the node MUST drop
   the echo request packet and not send any response back.  All
   responses MUST always be sent on a LSP path using the ACH header and



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   ACH channel type of LSP-Ping.

4.3.  P2MP Considerations

   [I-D.ietf-mpls-p2mp-lsp-ping] describes how LSP-Ping can be used for
   OAM on P2MP LSPs.  The procedures described in this draft apply as is
   irrespective of whether we use the mechanism specified in Section 4.1
   or the mechanism specified in Section 4.2.

4.4.  ECMP Considerations

   LSP-Ping using ACH SHOULD NOT be used when there is ECMP (equal cost
   multiple paths) for a given LSP.  The addition of the additional ACH
   header may modify the hashing behavior for OAM packets which may
   result in incorrect modeling of path taken by data traffic.


5.  Running BFD over MPLS-TP LSPs

   [I-D.ietf-bfd-mpls] describes how BFD can be used for Continuity
   Check for MPLS LSPs.  When IP addressing is in use, the procedures
   described in [I-D.ietf-bfd-mpls] apply as is.  This section clarifies
   the usage of BFD in the context of MPLS-TP LSPs when it is not
   desirable to use IP encapsulation.  When using BFD over MPLS-TP LSPs,
   the BFD descriminator MAY either be signaled via LSP-Ping or be
   statically configured.  The BFD packets MUST be sent over ACH when IP
   encapsulation is not used.  BFD packets, for both directions, MUST be
   sent over the MPLS-TP LSP and IP forwarding SHOULD NOT be used for
   the reverse path.  The format of a BFD packet when using it as an OAM
   tool for MPLS-TP LSPs SHOULD be as follows:

       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 2
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         MPLS Label stack                      |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                          GAL                                  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |0 0 0 1|Version|   Reserved    |        Channel Type           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            Payload depending on channel type                  |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                  Figure 5: BFD packet over MPLS-TP LSPs




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   [I-D.ietf-pwe3-vccv-bfd] specifies how BFD can be used over MPLS PWs.
   Of specific interest are 2 modes:

   1.  Channel type is IP and payload contains BFD packet with IP/UDP
       headers.
   2.  Channel type is BFD and payload contains BFD packet without IP/
       UDP headers.
   The first mode MUST be supported for BFD over MPLS-TP LSPs.  The
   second mode MAY be supported in addition.

   Thus, no changes in BFD and no new code-points are needed to run BFD
   over MPLS-TP LSPs.  BFD supports continuous fault monitoring and thus
   meets the Continuity Check requirement specified in
   [I-D.ietf-mpls-tp-oam-requirements].  For point to multipoint
   Continuity Check, there is work in progress on using BFD for P2MP
   MPLS LSPs ( [I-D.katz-ward-bfd-multipoint]) and this can be leveraged
   for MPLS-TP LSPs as well.


6.  Applicability

   The procedures described in this document apply to MPLS LSPs and as
   well as to LSPs based on the MPLS-TP profile.  The LSP-Ping
   procedures can be used for performing OAM on both LSPs and
   Pseudowires.


7.  Security Considerations

   The draft does not introduce any new security considerations.  Those
   discussed in [RFC4379] are also applicable to this document.


8.  IANA Considerations

8.1.  New ACH Channel Type

   A new Channel type is defined in Section 2.1.  IANA is requested to
   assign a new value from the "PW Associated Channel Type" registry, as
   per IETF consensus policy.

       Value    Meaning
       -----    -------
        TBD     Associated Channel carries LSP-Ping packet







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8.2.  New LSP-Ping TLV Types

   New TLV types are defined in Section 2.4 and Section 2.5.  IANA is
   requested to assign values from the "Multi-Protocol Label Switching
   (MPLS) Label Switched Paths (LSPs) Parameters" registry, "TLVs and
   sub-TLVs" sub- registry from the range of 32768-64511.

       Value    Meaning
       -----    -------
        TBD     Source Address
        TBD     Destination Address



9.  References

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4379]  Kompella, K. and G. Swallow, "Detecting Multi-Protocol
              Label Switched (MPLS) Data Plane Failures", RFC 4379,
              February 2006.

   [RFC4385]  Bryant, S., Swallow, G., Martini, L., and D. McPherson,
              "Pseudowire Emulation Edge-to-Edge (PWE3) Control Word for
              Use over an MPLS PSN", RFC 4385, February 2006.

9.2.  Informative References

   [I-D.ietf-bfd-mpls]
              Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow,
              "BFD For MPLS LSPs", draft-ietf-bfd-mpls-07 (work in
              progress), June 2008.

   [I-D.ietf-mpls-lsp-ping-enhanced-dsmap]
              Bahadur, N., Kompella, K., and G. Swallow, "Mechanism for
              performing LSP-Ping over MPLS tunnels",
              draft-ietf-mpls-lsp-ping-enhanced-dsmap-02 (work in
              progress), February 2009.

   [I-D.ietf-mpls-p2mp-lsp-ping]
              Yasukawa, S., Farrel, A., Ali, Z., Fenner, B., Swallow,
              G., and T. Nadeau, "Detecting Data Plane Failures in
              Point-to-Multipoint Multiprotocol Label  Switching (MPLS)
              - Extensions to LSP Ping",
              draft-ietf-mpls-p2mp-lsp-ping-07 (work in progress),



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              September 2008.

   [I-D.ietf-mpls-tp-framework]
              Bocci, M., Bryant, S., and L. Levrau, "A Framework for
              MPLS in Transport Networks",
              draft-ietf-mpls-tp-framework-01 (work in progress),
              June 2009.

   [I-D.ietf-mpls-tp-oam-requirements]
              Vigoureux, M., Ward, D., and M. Betts, "Requirements for
              OAM in MPLS Transport Networks",
              draft-ietf-mpls-tp-oam-requirements-02 (work in progress),
              June 2009.

   [I-D.ietf-pwe3-vccv-bfd]
              Nadeau, T. and C. Pignataro, "Bidirectional Forwarding
              Detection (BFD) for the Pseudowire Virtual Circuit
              Connectivity Verification (VCCV)",
              draft-ietf-pwe3-vccv-bfd-05 (work in progress), June 2009.

   [I-D.katz-ward-bfd-multipoint]
              Katz, D. and D. Ward, "BFD for Multipoint Networks",
              draft-katz-ward-bfd-multipoint-02 (work in progress),
              February 2009.

   [RFC1122]  Braden, R., "Requirements for Internet Hosts -
              Communication Layers", STD 3, RFC 1122, October 1989.

   [RFC1812]  Baker, F., "Requirements for IP Version 4 Routers",
              RFC 1812, June 1995.

   [RFC5586]  Bocci, M., Vigoureux, M., and S. Bryant, "MPLS Generic
              Associated Channel", RFC 5586, June 2009.


Authors' Addresses

   Nitin Bahadur (editor)
   Juniper Networks, Inc.
   1194 N. Mathilda Avenue
   Sunnyvale, CA  94089
   US

   Phone: +1 408 745 2000
   Email: nitinb@juniper.net
   URI:   www.juniper.net





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Internet-Draft        LSP-Ping and BFD for MPLS-TP             July 2009


   Rahul Agrawal
   Juniper Networks, Inc.
   1194 N. Mathilda Avenue
   Sunnyvale, CA  94089
   US

   Phone: +1 408 745 2000
   Email: rahul@juniper.net
   URI:   www.juniper.net


   Thomas D. Nadeau
   BT
   BT Centre
   81 Newgate Street
   London  EC1A 7AJ
   United Kingdom

   Email: tom.nadeau@bt.com


   Nurit Sprecher
   Nokia Siemens Networks
   3 Hanagar St. Neve Ne'eman B
   Hod Hasharon  45241
   Israel

   Phone: +972-9-775 1229
   Email: nurit.sprecher@nsn.com


   Yaacov Weingarten
   Nokia Siemens Networks
   3 Hanagar St. Neve Ne'eman B
   Hod Hasharon  45241
   Israel

   Phone: +972-9-775 1827
   Email: yaacov.weingarten@nsn.com












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