Network Working Group                                         N. Bahadur
Internet-Draft                                               R. Aggarwal
Intended status: Standards Track                  Juniper Networks, Inc.
Expires: January 27, 2011                                     S. Boutros
                                                     Cisco Systems, Inc.
                                                                 E. Gray
                                                                Ericsson
                                                           July 26, 2010


 MPLS on-demand Connectivity Verification, Route Tracing and Adjacency
                              Verification
                   draft-ietf-mpls-tp-on-demand-cv-00

Abstract

   LSP-Ping is an existing and widely deployed OAM mechanism for MPLS
   LSPs.  This document describes extensions to LSP-Ping so that LSP-
   Ping can be used to perform OAM on MPLS-TP LSPs.  It also clarifies
   the procedures to be used for processing the OAM packets.  Further,
   it describes how LSP-Ping can be used to perform Connectivity
   Verification, Route Tracing and Adjacency functions in MPLS-TP
   networks.

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on January 27, 2011.

Copyright Notice



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   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the BSD License.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1.  Conventions used in this document  . . . . . . . . . . . .  4
     1.2.  LSP-Ping for MPLS-TP LSPs using IP encapsulation . . . . .  4
     1.3.  LSP-Ping for MPLS-TP LSPs using non-IP encapsulation . . .  4
   2.  LSP-Ping extensions  . . . . . . . . . . . . . . . . . . . . .  5
     2.1.  New address type for Downstream Mapping TLV  . . . . . . .  5
     2.2.  Source Address TLV . . . . . . . . . . . . . . . . . . . .  5
     2.3.  MEP and MIP Identifier . . . . . . . . . . . . . . . . . .  5
     2.4.  Identifying Statically provisioned LSPs and PWs  . . . . .  6
       2.4.1.  Static LSP Sub-TLV . . . . . . . . . . . . . . . . . .  6
       2.4.2.  Static Pseudowire Sub-TLV  . . . . . . . . . . . . . .  7
   3.  Performing LSP-Ping over MPLS-TP LSPs  . . . . . . . . . . . .  7
     3.1.  LSP-Ping with IP encapsulation . . . . . . . . . . . . . .  7
     3.2.  LSP-Ping with IP encapsulation, over ACH . . . . . . . . .  8
     3.3.  Non-IP based LSP-Ping  . . . . . . . . . . . . . . . . . .  8
     3.4.  Reverse path Connectivity verification . . . . . . . . . .  9
     3.5.  P2MP Considerations  . . . . . . . . . . . . . . . . . . .  9
   4.  Performing LSP Traceroute over MPLS-TP LSPs  . . . . . . . . .  9
     4.1.  LSP Traceroute with IP encapsulation . . . . . . . . . . . 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  . . . . . . . . . . . . . . . . . . . 10
     4.4.  ECMP Considerations  . . . . . . . . . . . . . . . . . . . 11
   5.  Applicability  . . . . . . . . . . . . . . . . . . . . . . . . 11
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 11
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 11
   8.  Contributing Authors . . . . . . . . . . . . . . . . . . . . . 11
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 12



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     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 12
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 12
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13
















































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1.  Introduction

   LSP-Ping [RFC4379] is an OAM mechanism for MPLS LSPs.  This document
   describes extensions to LSP-Ping so that LSP-Ping can be used for on-
   demand monitoring of MPLS-TP LSPs.  It also clarifies the procedures
   to be used for processing the OAM packets.  This document describes
   how LSP-Ping can be used to perform on-demand Connectivity
   Verification, Route Tracing and Adjacency functions required in
   [RFC5860] and specified in [I-D.ietf-mpls-tp-oam-framework].

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.  LSP-Ping for MPLS-TP LSPs using IP encapsulation

   LSP-Ping requires IP addressing on the egress and transit LSRs for
   performing OAM on MPLS signaled LSPs and pseudowires.  In particular,
   in these cases the LSP-Ping 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] , [RFC5884]).  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
   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".

1.3.  LSP-Ping for MPLS-TP LSPs using non-IP encapsulation

   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.  In such scenarios, LSP-Ping SHOULD be run
   without IP addressing, using the ACH channel type specified in
   [I-D.ietf-mpls-tp-lsp-ping-bfd-procedures].

   Section 3.3 and Section 4.2 describe the theory of operation for
   performing LSP-Ping over MPLS-TP LSPs with a non-IP encapsulation.







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2.  LSP-Ping extensions

2.1.  New address type for Downstream Mapping TLV

   [RFC4379] defines the Downstream Mapping TLV.  This document defines
   the following new Address type which is added to the Downstream
   Mapping TLV:

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


             Figure 1: Downstream Mapping TLV new address type

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

   When this address type is used, on receipt of a LSP-Ping echo
   request, interface verification MUST be bypassed.  Thus the receiving
   node SHOULD only perform mpls label control-plane/data-plane
   consistency checks.

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

2.2.  Source Address TLV

   When sending LSP-Ping packets using ACH, without IP encapsulation,
   there MAY be a need to identify the source address of the packet.
   This source address will be specified via the Source Address TLV,
   being defined in [I-D.ietf-mpls-tp-ach-tlv].  A LSP-Ping packet MUST
   NOT include more than 1 source address TLV.  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 1
   (Malformed echo request received), [ Section 3.1 [RFC4379] ], MUST be
   returned, if it is possible to unambiguously identify the source of
   the packet.

2.3.  MEP and MIP Identifier

   When sending LSP-Ping packets using ACH, there MAY be a need to
   identify the maintenance end point (MEP) and/or the maintenance
   intermediate point (MIP) being monitored
   [I-D.ietf-mpls-tp-rosetta-stone].  The MEP/MIP identifiers defined in
   [I-D.ietf-mpls-tp-identifiers] MAY be carried in the ACH TLVs
   [I-D.ietf-mpls-tp-ach-tlv] for identification.  Only one identifier



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   (MEP or MIP) MUST be present in a packet.  The MEP/MIP identifiers
   associated with the packet MUST be checked for the MPLS-TP LSP path/
   section that is being monitored.  If the identifier does not match
   the LSP path/section, then the packet MUST be dropped.

2.4.  Identifying Statically provisioned LSPs and PWs

   [RFC4379] specifies how an MPLS LSP under test may be identified in
   an echo request.  A Target FEC Stack TLV is used to identify the LSP.
   In order to identify a statically provisioned LSP and PW, new target
   FEC stack sub-TLVs are being defined.  The new sub-TLVs are assigned
   sub-type identifiers as follows, and are described in the following
   sections.

        Sub-Type #       Length              Value Field
         ----------       ------              -----------
                TBD         24                Static LSP
                TBD         24                Static Pseudowire

                    Figure 2: New target FEC sub-types

2.4.1.  Static LSP Sub-TLV

   The format of the Static LSP sub-TLV value field is specified in the
   following figure.  The value fields are taken from the definitions in
   [I-D.ietf-mpls-tp-identifiers].

        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 Global ID                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Source Node ID                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |     Source Tunnel Number      |        LSP Number             |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Destination Global ID                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Destination Node ID                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |   Destination Tunnel Number   |        Must be Zero           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                     Figure 3: Static LSP FEC Sub-TLV

   The Source global ID and Destination Global ID MAY be set to 0.  When
   set to zero, the field is not applicable.



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2.4.2.  Static Pseudowire Sub-TLV

   The format of the Static PW sub-TLV value field is specified in the
   following figure.

        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 Global ID                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Source Node ID                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Source AC-ID                          |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Destination Global ID                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Destination Node ID                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Destination AC-ID                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                      Figure 4: Static PW FEC Sub-TLV

   The Source global ID and Destination Global ID MAY be set to 0.  When
   set to zero, the field is not applicable.  The Global ID and Node ID
   fields are taken from the definitions in
   [I-D.ietf-mpls-tp-identifiers].  The AC-ID definitions are taken from
   [RFC5003].


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 [RFC5860].  This function
   SHOULD be performed on-demand.  This function SHOULD be performed
   between End Points (MEPs) and Intermediate Points (MIPs) of PWs and
   LSPs, and between End Points of PWs, LSPs and Sections.  In order for
   the LSP-Ping packet to be processed at the desired MIP, the TTL of
   the MPLS label should be set such that it expires at the MIP to be
   probed.

3.1.  LSP-Ping with IP encapsulation

   LSP-Ping packets, as specified in [RFC4379], are sent over the MPLS
   LSP for which OAM is being performed and contain an IP/UDP packet
   within them.  The IP header is not used for forwarding (since LSP



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   forwarding is done 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 LSP-Ping echo response 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 echo request message.  The source
   address in the IP address MUST be set to a valid address of the
   replying node.

3.2.  LSP-Ping with IP encapsulation, over ACH

   IP encapsulated LSP-Ping packets MAY be sent over the MPLS LSP using
   control channel (ACH).  IP ACH type specified in [RFC4385] MUST be
   used in such a case.  The IP header is used mainly for addressing and
   can be used in the context of MPLS-TP LSPs.

   The LSP-Ping echo response message SHOULD be sent on the reverse path
   of the LSP using ACH and SHOULD be IP encapsulated.  The destination
   address in the IP header MUST be set to that of the sender of the
   echo request message.  The source address in the IP address MUST be
   set to a valid address of the replying node.

3.3.  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 addressing and routing.

   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 2.2) 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 any ACH TLVs) and no IP and/or UDP headers MUST be
   attached.  The responding node MAY attach a Source Address TLV to
   identify the node sending the response.

   If a node receives an MPLS echo request packet over ACH, without IP/
   UDP headers and if that node does not have a return MPLS LSP path to



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   the echo request source, then the node MUST drop the echo request
   packet and not attempt to send a response.

3.4.  Reverse path Connectivity verification

   For bi-directional LSPs, when the egress sends the echo response, the
   egress MAY attach the target FEC stack TLV [RFC4379] in the echo
   response.  The ingress (on receipt of the echo response) can use the
   FEC stack TLV to perform reverse path connectivity verification.  For
   co-routed bi-directional LSPs, the target FEC stack used for LSP-Ping
   will be the same in both the forward and reverse path of the LSP.
   For associated bi-directional LSPs, the target FEC stack will be
   different for the reverse path.

   On receipt of the echo response, the ingress MUST perform the
   following checks:

   1.  Perform interface and label-stack validation to ensure that the
       packet is received on the reverse path of the bi-directional LSP
   2.  If the target FEC stack is present in the echo response, then
       perform FEC validation.
   If any of the validations fail, then the ingress MUST drop the echo
   response and report an error.

3.5.  P2MP Considerations

   [I-D.ietf-mpls-p2mp-lsp-ping] describes how LSP-Ping can be used for
   OAM on P2MP LSPs with IP encapsulation.  This MUST be supported for
   MPLS-TP P2MP LSPs when IP addressing is used.  When IP addressing is
   not used, then the procedures described in Section 3.3 can be applied
   to P2MP MPLS-TP LSPs as well.


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
   Adjacency and Route Tracing requirement specified in [RFC5860].  This
   function SHOULD be performed on-demand.  This function SHOULD be
   performed between End Points and Intermediate Points of PWs and LSPs,
   and between End Points of PWs, LSPs and Sections.

   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 2.1).



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   The Downstream Mapping TLV address type field can be extended to
   include other address types as need be.

4.1.  LSP Traceroute with IP encapsulation

   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 follow procedures described in [RFC4379].  This form of LSP-Ping
   OAM MUST be supported for MPLS-TP LSPs, when IP addressing is used.

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 3.3 with regards to
   Source Address TLV, MEP/MIP identifiers 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 3.3.  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, the label stack and the
   MEP/MIP identifier should be sufficient to identify the LSP
   associated with the echo request packet.  If there is an error and
   the node is unable to identify the LSP on which the echo response
   would 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 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.  This MUST be supported for MPLS-TP P2MP LSPs when
   IP addressing is used.  When IP addressing is not used, then the



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   procedures described in Section 4.2 can be applied to P2MP MPLS-TP
   LSPs as well.

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 monitoring of path taken by data traffic.


5.  Applicability

   The non-IP addressing based procedures specified in this document
   apply only to MPLS-TP LSPs.  They also apply to PWs when IP
   encapsulation is not desired.  However, when IP addressing is used,
   as in non MPLS-TP LSPs, procedures specified in [RFC4379] MUST be
   used.


6.  Security Considerations

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


7.  IANA Considerations

   Section 2.4 defines 2 new sub-TLV types for inclusion within the LSP
   Ping [RFC4379] Target FEC Stack TLV.

   IANA is requested to assign sub-type values to the following sub-TLVs
   from the "Multiprotocol Label Switching Architecture (MPLS) Label
   Switched Paths (LSPs) Parameters - TLVs" registry, "TLVs and sub-
   TLVs" sub-registry.

   - Static LSP
   - Static Pseudowire



8.  Contributing Authors

   The following individuals also contributed to this document:
   o  Thomas D. Nadeau, BT
   o  Nurit Sprecher, Nokia Siemens Networks





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   o  Yaacov Weingarten, Nokia Siemens Networks


9.  References

9.1.  Normative References

   [I-D.ietf-mpls-tp-lsp-ping-bfd-procedures]
              Bahadur, N., Aggarwal, R., Ward, D., Nadeau, T., Sprecher,
              N., and Y. Weingarten, "LSP-Ping and BFD encapsulation
              over ACH", draft-ietf-mpls-tp-lsp-ping-bfd-procedures-00
              (work in progress), March 2010.

   [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-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-05 (work in
              progress), May 2010.

   [I-D.ietf-mpls-p2mp-lsp-ping]
              Yasukawa, S., Farrel, A., Ali, Z., Swallow, G., Nadeau,
              T., and S. Saxena, "Detecting Data Plane Failures in
              Point-to-Multipoint Multiprotocol Label Switching (MPLS) -
              Extensions to LSP Ping", draft-ietf-mpls-p2mp-lsp-ping-10
              (work in progress), March 2010.

   [I-D.ietf-mpls-tp-ach-tlv]
              Boutros, S., Bryant, S., Sivabalan, S., Swallow, G., Ward,
              D., and V. Manral, "Definition of ACH TLV Structure",
              draft-ietf-mpls-tp-ach-tlv-02 (work in progress),
              March 2010.

   [I-D.ietf-mpls-tp-identifiers]
              Bocci, M. and G. Swallow, "MPLS-TP Identifiers",
              draft-ietf-mpls-tp-identifiers-02 (work in progress),



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              March 2010.

   [I-D.ietf-mpls-tp-oam-framework]
              Allan, D., Busi, I., Niven-Jenkins, B., Fulignoli, A.,
              Hernandez-Valencia, E., Levrau, L., Mohan, D., Sestito,
              V., Sprecher, N., Helvoort, H., Vigoureux, M., Weingarten,
              Y., and R. Winter, "MPLS-TP OAM Framework",
              draft-ietf-mpls-tp-oam-framework-07 (work in progress),
              April 2010.

   [I-D.ietf-mpls-tp-rosetta-stone]
              Sprecher, N., "A Thesaurus for the Terminology used in
              Multiprotocol Label Switching Transport Profile (MPLS-TP)
              drafts/RFCs and ITU-T's Transport Network
              Recommendations.", draft-ietf-mpls-tp-rosetta-stone-02
              (work in progress), May 2010.

   [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.

   [RFC5003]  Metz, C., Martini, L., Balus, F., and J. Sugimoto,
              "Attachment Individual Identifier (AII) Types for
              Aggregation", RFC 5003, September 2007.

   [RFC5860]  Vigoureux, M., Ward, D., and M. Betts, "Requirements for
              Operations, Administration, and Maintenance (OAM) in MPLS
              Transport Networks", RFC 5860, May 2010.

   [RFC5884]  Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow,
              "Bidirectional Forwarding Detection (BFD) for MPLS Label
              Switched Paths (LSPs)", RFC 5884, June 2010.


Authors' Addresses

   Nitin Bahadur
   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  MPLS on-demand Connectivity Verification       July 2010


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

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


   Sami Boutros
   Cisco Systems, Inc.
   3750 Cisco Way
   San Jose, CA  95134
   US

   Phone:
   Fax:
   Email: sboutros@cisco.com
   URI:


   Eric Gray
   Ericsson
   900 Chelmsford Street
   Lowell, MA  01851
   US

   Phone: +1 978 275 7470
   Fax:
   Email: eric.gray@ericsson.com
   URI:


















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