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Versions: (draft-martini-pwe3-p2mp-pw) 00 01 02 03 04

Internet Engineering Task Force                             Sami Boutros
Internet Draft                                              Luca Martini
Expiration Date: September 2011                           Siva Sivabalan
Intended status: Standards Track                                   Cisco

Maciek Konstantynowicz
Juniper

Frederic Jounay                                       Gianni Del Vecchio
Philippe Niger                                                  Swisscom
France Telecom

Thomas D. Nadeau                                             Yuji Kamite
Huawei                                                NTT Communications

Simon Delord                                                 Lizhong Jin
Telstra                                                              ZTE

Laurent Ciavaglia
Martin Vigoureux
Alcatel-Lucent
                                                           March 2, 2011


   Signaling Root-Initiated Point-to-Multipoint Pseudowires using LDP


                     draft-ietf-pwe3-p2mp-pw-02.txt

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
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   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.





Boutros, et al.                                                 [Page 1]

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

   This Internet-Draft will expire on September 2, 2010

Abstract

   This document specifies a mechanism to signal Point-to-Multipoint
   (P2MP) Pseudowires (PW) tree using LDP. Such a mechanism is suitable
   for any Layer 2 VPN service requiring P2MP connectivity over an IP or
   MPLS-enabled PSN. A P2MP PW established via the proposed mechanism is
   root initiated.



Table of Contents

    1        Specification of Requirements  ........................   3
    2        Introduction  .........................................   3
    3        Terminology  ..........................................   4
    4        Signaling the P2MP PW  ................................   5
    4.1      PW ingress to egress incompatibility issues  ..........   6
    4.2      P2MP PW FEC Element  ..................................   7
    4.3      Group ID usage  .......................................   9
    4.4      Generic Label TLV  ....................................   9
    4.5      Transport LSP TLV  ....................................  10
    5        LDP Capability Negotiation  ...........................  12
    6        P2MP PW status  .......................................  13
    7        Security Considerations  ..............................  13
    8        IANA Considerations  ..................................  13
    8.1      FEC Type Name Space  ..................................  13
    8.2      LDP TLV TYPE  .........................................  14
    8.3      mLDP Opaque Value Element TLV TYPE  ...................  14
    9        References  ...........................................  14
    9.1      Normative References  .................................  14
    9.2      Informative References  ...............................  15
   10        Author's Addresses  ...................................  16














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1. Specification of Requirements

   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].



2. Introduction

   A Point-to-Multipoint (P2MP) Pseudowire (PW) emulates the essential
   attributes of a unidirectional P2MP Telecommunications service such
   as P2MP ATM over PSN. A major difference between a Point-to-Point
   (P2P) PW outlined in [RFC3985] and a P2MP PW is that the former is
   intended for bidirectional service whereas the latter is intended for
   both unidirectional, or optionally bidirectional service.
   Requirements for P2MP PW are described in [P2MP-PW-REQ].

   P2MP PW can be constructed as either Single Segment (P2MP SS-PW) or
   Multi Segment (P2MP MS-PW) Pseudowires as mentioned in [P2MP-PW-REQ].
   P2MP MS-PW is outside the scope of this document.  A reference model
   for P2MP PW is depicted in Figure 1 below. A transport LSP associated
   with a P2MP SS-PW SHOULD be a P2MP MPLS LSP (i.e., P2MP TE tunnel
   established via RSVP-TE [RFC4875] or P2MP LSP established via mLDP
   [mLDP]) spanning from the Root-PE to the Leaf-PE(s) of the P2MP SS-PW
   tree. For example, in Figure 1, PW1 can be associated with a P2MP TE
   tunnel or P2MP LSP setup using [mLDP] originating from PE1 and
   terminating at PE2 and PE3.























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                |<--------------P2MP PW---------------->|
         Native |                                       |  Native
        Service |     |<--PSN1->|      |<--PSN2->|      |  Service
         (AC)   V     V         V      V         V      V   (AC)
           |    +-----+         +------+         +------+    |
           |    |     |         |   P1 |=========|T-PE2 |AC3 |    +---+
           |    |     |         |   .......PW1.........>|-------->|CE3|
           |    |T-PE1|=========|   .  |=========|      |    |    +---+
           |    |  .......PW1........  |         +------+    |
           |    |  .  |=========|   .  |         +------+    |
           |    |  .  |         |   .  |=========|T-PE3 |AC4 |    +---+
   +---+   |AC1 |  .  |         |   .......PW1.........>|-------->|CE4|
   |CE1|------->|...  |         |      |=========|      |    |    +---+
   +---+   |    |  .  |         +------+         +------+    |
           |    |  .  |         +------+         +------+    |
           |    |  .  |=========|   P2 |=========|T-PE4 |AC5 |    +---+
           |    |  .......PW1..............PW1.........>|-------->|CE5|
           |    |     |=========|      |=========|      |    |    +---+
           |    +-----+         +------+         +------+    |

                              Figure 1: P2MP PW


   Mechanisms for establishing P2P SS-PW using LDP are described in
   [RFC4447].  In this document, we specify a method to signal P2MP PW
   using LDP. In particular, we define new TLVs, parameters, and status
   codes to facilitate LDP to signal and maintain P2MP PWs.

   Note that even though the traffic flow from a Root-PE to Leaf-PE(s)
   is P2MP in nature, it may be desirable for any Leaf-PE to send
   unidirectional P2P traffic destined only to the Root-PE. The proposed
   mechanism takes such an option into consideration.

   The P2MP PW requires an MPLS LSP to carry the PW traffic. the PW MPLS
   packet will be encapsulated according to the methods described in
   [RFC5332].


3. Terminology

   FEC: Forwarding Equivance Class

   LDP: Label Distribution Protocol

   mLDP: Label Distribution Protocol for P2MP LSP

   LSP: Label Switching Path




Boutros, et al.                                                 [Page 4]

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   MS-PW: Multi-Segment Pseudowire

   P2P: Point to Point

   P2MP: Point to Multipoint

   PE: Provider Edge

   PSN: Packet Switched Network

   PW: Pseudowire

   SS-PW: Single-Segment Pseudowire

   S-PE: Switching Provider Edge Node of MS-PW

   TE: Traffic Engineering

   R-PE: Root-PE - ingress PE, PE initiating P2MP PW setup.

   L-PE: Leaf-PE - egress PE.


4. Signaling the P2MP PW

   In order to advertise labels as well as exchange PW related LDP
   messages, PEs must establish LDP sessions among themselves using the
   Extended Discovery Mechanisms. A PE discovers other PEs that are to
   be connected via P2MP PWs either via manual configuration or
   autodiscovery [RFC6074].

   Root-PE and each Leaf-PE MUST be configured with the same FEC as
   defined in the following section.

   P2MP PW requires that there is an active P2MP PSN LSP set up between
   Root-PE and Leaf-PE(s). Note that the procedure to set up the P2MP
   PSN LSP is different depending on the protocol used: RSVP-TE or mLDP.

   In case of mLDP a Leaf-PE can decide to join the P2MP LSP at any
   time, while in case of RSVP-TE the P2MP LSP is set up by the Root-PE,
   generally at the initial service provisioning time. It should be
   noted that local policy can override any decision to join, add or
   prune existing or new Leaf-PE(s) from the tree.

   In any case the PW setup can ignore these differences, and simply
   assume that the P2MP tunnel is available when needed.

   The P2MP PW is initiated by the root (source) Provider Edge router



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   (R-PE), by simply sending an P2MP-PW LDP label mapping message to all
   the Leaf Provider Edge routers L-PEs. This label mapping message will
   contain the following:
        -i. P2MP PW FEC element.
       -ii. an Interface Parameters TLV,  as described in [RFC4447] sec
            5.3.2.1
      -iii. a PW Grouping TLV, as described in [RFC4447] sec 5.3.2.2
       -iv. a Transport LSP TLV.
        -v. a label TLV for the upstream-assigned label R-PE to L-PE
            direction.
       -vi. MAY contain a downstream-assigned label for the L-PE to R-PE
            direction.

   The LDP liberal label retention mode is used, and per [RFC5036]
   requirement the label request message MUST also be supported.

   The Upstream-assigned label is allocated according to the rules in
   [RFC5331].

   When a Leaf-PE receives a PW Label Mapping Message, it MUST verify
   the associated P2MP transport LSP is in place.

   If the associated transport P2MP LSP is not in place, and the
   transport LSP TLV type is LDP P2MP LSP, a Leaf-PE SHOULD attempt to
   join the P2MP transport associated with the P2MP PW.

   If the associated transport P2MP LSP is not in place, and the
   transport LSP TLV type is RSVP-TE P2MP LSP, a Leaf-PE SHOULD await
   RSVP-TE P2MP LSP signaling from the Root-PE.


4.1. PW ingress to egress incompatibility issues

   If a Root-PE signals a PW with a pw type, CW mode, or interface
   parameters that a particular Leaf-PE cannot accept, then the L-PE
   must simply not enable the PW, and notify the user. In this case a PW
   status message of 0x00000001 - Pseudowire Not Forwarding MUST also be
   sent to the R-PE.

   Note that this procedure does not apply if the L-PE had not been
   provisioned with this particular P2MP PW. In this case according to
   the LDP liberal label retention rules, no action is taken.









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4.2. P2MP PW FEC Element

   [RFC4447] specifies two types of LDP FEC elements called "PWid FEC
   Element" and "Generalized PWid FEC Element" used to signal P2P PWs.
   We define a new type of FEC element called "P2MP PW FEC Element"
   whose type is 0x82 (Pending IANA Allocation) and is encoded 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |FEC Type = 0x82|C|           PW Type           | PW Info Length|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    AGI Type   |     Length    |         AGI Value             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~                       AGI Value (contd.)                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    AII Type   |     Length    |         SAII Value            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~                       SAII Value (contd.)                     ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |0|0| Transport LSP TLV (0x0971)|           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Reserved     |PMSI Tunnel Typ|       Transport LSP ID        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~                   Transport LSP ID (contd.)                   ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   |                       Optional Parameters                     |
   ~                                                               ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                   Figure 2: P2MP PW FEC Element

     * PW Type:

       15-bit representation of PW type, and the assigned values are
       assigned by IANA.

     * C bit:

       A value of 1 or 0 indicates whether control word is present or
       absent for the P2MP PW.




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     * PW Info Length:

       Sum of the lengths of AGI, SAII and Optional Parameters field in
       octets. If this value is 0, then it references all PWs using the
       specified grouping ID.  In this case, there are no other FEC
       element fields (AGI, SAII, etc.)  present, nor any interface
       parameters TLVs.

     * AGI:

       Attachment Group Identifier can be used to uniquely identify VPN
       or VPLS instance associated with the P2MP PW. This has the same
       format as that of the Generalized PWid FEC element [RFC4447].

     * SAII:

       Source Attachment Individual Identifier is used to identify the
       root of the P2MP PW. The root is represented using AII type 2
       format specified in [RFC5003].  Note that the SAII can be omitted
       by simply setting the length and type to zero.

       P2MP PW is identified by the Source Attachment Identifier (SAI).
       If the AGI is non-null, the SAI is the combination of the SAII
       and the AGI, if the AGI is null, the SAI is the SAII.

     * Transport LSP TLV:

       A P2MP PW MUST be associated with a transport LSP. The Transport
       LSP TLV contains the information required to identify the
       transport LSP. Note that the Transport LSP TLV MUST immediately
       follow the FEC , but is not part of the FEC, and SHOULD NOT be
       used in other messages where the FEC is used.

     * Optional Parameters:

       The Optional Parameter field can contain some TLVs that are not
       part of the FEC, but are necessary for the operation of the PW.
       This document defines two such parameters: Interface Parameters
       TLV, and Group ID TLV.

   The Interface Parameters TLV and Group ID TLV specified in [RFC4447]
   can also be used in conjunction with P2MP PW FEC. For Group ID TLV
   the sender and receiver of these TLVs should follow the same rules
   and procedures specified in [RFC4447]. For Interface Parameters TLV
   the procedure differs from the one specified in [RFC4447] due to
   specifics of P2MP connectivity. When the interface parameters are
   signaled by the Root-PE, the Leaf-PE must check if its configured
   value(s) is less than or equal to the threshold value provided by the



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   Root-PE (e.g. MTU size (Ethernet), max number of concatenated ATM
   cells, etc)). For other interface parameters like CEP/TDM Payload
   bytes (TDM), the value MUST match exactly the the one signaled by the
   Root-PE.

   Note that since the LDP label mapping message is only sent by the R-
   PE to all the L-PEs it is not possible to negotiate any interface
   parameters.


4.3. Group ID usage

   The Grouping TLV as defined in [RFC4447] contains a group ID capable
   of indicating an arbitrary group membership of a P2MP-PW. This group
   ID can be used in LDP "wild card" status, and withdraw label
   messages, as described in [RFC4447].


4.4. Generic Label TLV

   For a given P2MP PW, a single upstream-assigned label is allocated by
   the Root-PE, and is advertised to all Leaf-PEs using the Generic
   Label TLV in the label mapping message containing the P2MP PW FEC
   element. The Root-PE imposes the upstream-assigned label on the
   outbound packets sent over the P2MP-PW, and using this label a Leaf-
   PE identifies the inbound packets arriving over the P2MP PW. Even
   though the P2MP PW is unidirectional, it may be possible for a Root-
   PE to receive traffic from any Leaf-PE using a unidirectional P2P PW
   in the reverse direction as outlined in [P2MP-PW-REQ]. For this
   purpose, the Root-PE can also allocate a unique downstream-assigned
   label for each Leaf-PE from which it is intended to receive P2P
   traffic. In other words, Label Mapping Message for a P2MP PW from a
   Root-PE to a Leaf-PE MUST carry a upstream-assigned label and MAY
   carry an OPTIONAL downstream-assigned label.

   As in the case of P2P PW signaling, P2MP PW labels are carried within
   Generic Label TLV contained in LDP Label Mapping Message. A Generic
   Label TLV is formatted and processed as per the rules and procedures
   specified in [RFC4447]. But, as mentioned above, a Label Mapping
   Message for a P2MP PW can have up to two Generic Label TLVs; one for
   upstream-assigned label (always) and another for downstream-assigned
   label (optional). In the case of two Generic Label TLVs, the first
   TLV (from the beginning of the message) carries upstream-assigned
   label and the next generic label TLV carries the downstream-assigned
   label as shown below:






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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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |0|0| Generic Label (0x0200)    |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Upstream-assigned P2MP Label (mandatory)           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |0|0| Generic Label (0x0200)    |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Downstream-assigned P2P Label (optional)           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     Figure 3: Generic Label TLVs in P2MP PW Label Mapping Message



   Note that other type of TLVs may appear between the above generic
   label TLVs, however any other generic label TLV MUST NOT appear
   between the upstream-assigned P2MP Label TLV, and downstream-assigned
   P2P Label TLV.


4.5. Transport LSP TLV

   A P2MP PW MUST be associated with a transport LSP which can be
   established using RSVP-TE or mLDP. Thus, a Label Mapping Message MUST
   contain the identity of the transport LSP. For this purpose, this
   specification introduces a new TLV called "Transport LSP TLV" which
   has the following format:

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |0|0| Transport LSP TLV (0x0971)|           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Reserved     |PMSI Tunnel Typ|       Tunnel Identifier       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~                   Tunnel Identifier (contd.)                  ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Figure 4: Transport LSP TLV

   Note: TLV number pending IANA allocation.







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     * Reserved Flags:

       Reserved bits Must be set to 0 when transmitting the message, and
       ignored on receiving the message.

     * PMSI Tunnel Type:

       The Transport LSP Type identifies the type of technology used to
       establish a transport LSP. The PMSI tunnel type is defined in
       [L3VPN-MCAST].

       When the type is set to mLDP P2MP LSP, the Tunnel Identifier is a
       P2MP FEC Element as defined in [mLDP]. A new mLDP Opaque Value
       Element type for L2VPN-MCAST application needs to be allocated.

       Editor Comment: The content of the Opaque Value Element TLV is a
       TBD.


     * Tunnel Identifier:

       The Tunnel containing the Transport LSP is identified by the
       Tunnel Identifier which is defined in [L3VPN-MCAST].

   Transport LSP TLV MUST be present only in the Label Mapping Message.
   An Root-PE sends Label Mapping Message as soon as the transport LSP
   ID associated with the P2MP PW is known (e.g., via configuration)
   regardless of the operational state of the transport LSP. Similarly,
   a Root-PE does not withdraw the labels when the corresponding
   transport LSP goes down.  Furthermore, a Leaf-PE retains the P2MP PW
   labels regardless of the operational status of the transport LSP.

   Note that a given transport LSP can be associated with more than one
   P2MP PW and all P2MP PWs will be sharing the same Root-PE and Leaf-
   PE(s).

   In the case of LDP P2MP LSP, when a Leaf-PE receives the Label
   Mapping Message, it can initiate the process of joining the P2MP LSP
   tree associated with the P2MP PW.

   In the case of RSVP-TE P2MP LSP, only the Root-PE initiates the
   signaling of P2MP LSP.









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5. LDP Capability Negotiation

   The capability of supporting P2MP PW must be advertised to all LDP
   peers.  This is achieved by using the methods in [RFC5561] and
   advertising the P2MP PW LDP capability TLV. If an LDP peer supports
   the dynamic capability advertisement, this can be done by sending a
   new capability message with the S bit set for the P2MP PW capability
   TLV. If the peer does not support dynamic capability advertisement,
   then the P2MP PW TLV MUST be included in the LDP initialization
   procedures in the capability parameter [RFC5561].

   In line with requirements listed in [RFC5561] the following TLV is
   defined to indicate the P2MP PW capability:

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |U|F| TLV Code Point=0x703      |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |S| Reserved    |    Reserved   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Figure 5: P2MP PW LDP Capability TLV

   Note: TLV number pending IANA allocation.

     * U-bit:

       SHOULD be 1 (ignore if not understood).

     * F-bit:

       SHOULD be 0 (don't forward if not understood).

     * TLV Code Point:

       The TLV type, which identifies a specific capability. The P2MP PW
       capability code point is requested in the IANA allocation section
       below.

     * S-bit:

       The State Bit indicates whether the sender is advertising or
       withdrawing the P2MP PW capability. The State bit is used as
       follows:
             1 - The TLV is advertising the capability specified by the
                 TLV Code Point.




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             0 - The TLV is withdrawing the capability specified by the
                 TLV Code Point.


6. P2MP PW status

   In order to support the proposed mechanism, a node MUST be capable of
   handling PW status. As such, PW status negotiation procedure
   described in [RFC4447] is not applicable to P2MP PW.

   Once a Leaf-PE successfully process a Label Mapping Message for a
   P2MP PW, it MUST send appropriate PW status according to the
   procedure specified [RFC4447] to notify the PW status. If there is no
   PW status notification required, then no PW status notification is
   sent. (for example if the P2MP PW is established and operational with
   a status 0f 0x00000000 no pw status message is necessary).

   PW status message sent from any Leaf-PE to Root-PE contains P2MP PW
   FEC to identify the PW. Finally, a Root-PE also sends PW status to
   Leaf-PE(s) to reflect its view of a P2MP PW state.

   Connectivity status of the underlying P2MP LSP that P2MP PW is
   associated with, can be verified using LSP Ping and Traceroute
   procedures described in [P2MP-LSP-PING].


7. Security Considerations

   The security measures described in [RFC4447] is adequate for the
   proposed mechanism.


8. IANA Considerations

8.1. FEC Type Name Space

   This document uses a new FEC element types, number 0x82 will be
   requested as an allocation from the registry "FEC Type Name Space"
   for the Label Distribution Protocol (LDP RFC5036):

   Value    Hex    Name                               Reference
   -------  -----  -----------------------------      ---------
    130     0x82   P2MP PW FEC Element                RFCxxxx








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8.2. LDP TLV TYPE

   This document uses a new LDP TLV types, IANA already maintains a
   registry of name "TLV TYPE NAME SPACE" defined by RFC5036. The
   following values are suggested for assignment:

      TLV type  Description
       0x0971   Transport LSP TLV
       0x0703   P2MP PW Capability TLV


8.3. mLDP Opaque Value Element TLV TYPE

   This document requires allocation of a new mLDP Opaque Value Element
   Type from the LDP MP Opaque Value Element type name space defined in
   [mLDP].

   The following value is suggested for assignment:

      TLV type  Description
      0x3       L2VPN-MCAST application TLV



9. References

9.1. Normative References

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

   [RFC4447] "Transport of Layer 2 Frames Over MPLS", Martini, L.,
        et al., rfc4447 April 2006.

   [RFC5036]  Andersson, L., Minei, I., and B. Thomas, "LDP
        Specification", RFC 5036, October 2007.

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

   [RFC5331] R. Aggarwal, Y. Rekhter, E. Rosen, "MPLS Upstream Label
        Assignment and Context-Specific Label Space", rfc5331,
        August 2008.

   [RFC5332] T. Eckert, E. Rosen, Ed.,R. Aggarwal, Y. Rekhter,
        "MPLS Multicast Encapsulations", rfc5332, August 2008.




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Internet Draft       draft-ietf-pwe3-p2mp-pw-02.txt        March 2, 2011


   [mLDP] I. Minei, K. Kompella, I. Wijnands, B. Thomas, "Label
        Distribution Protocol Extensions for Point-to-Multipoint and
        Multipoint-to-Multipoint Label Switched Paths",
        draft-ietf-mpls-ldp-p2mp-06, Work In Progress, April 2009.

   [RFC4875]
        R. Aggarwal, Ed., D. Papadimitriou, Ed., S. Yasukawa, Ed.,
        "Extensions to Resource Reservation Protocol - Traffic
        Engineering (RSVP-TE) for Point-to-Multipoint TE Label
        Switched Paths (LSPs).", rfc4875, May 2007.

   [L3VPN-MCAST] R. Aggarwal, E. Rosen, T. Morin, Y. Rekhter,
        "BGP Encodings and Procedures for Multicast in MPLS/BGP IP
        VPNs", draft-ietf-l3vpn-2547bis-mcast-bgp-08.txt,
        Work in Progress, October 2009.

   [RFC5561] B.Thomas, K.Raza, S.Aggarwal, R.Agarwal, JL. Le Roux,
        "LDP Capabilities", rfc5561, July 2009.


9.2. Informative References

   [RFC3985] Stewart Bryant, et al., "PWE3 Architecture",
        RFC3985

   [RFC6074] E. Rosen,W. Luo,B. Davie,V. Radoaca "Provisioning,
        Auto-Discovery, and Signaling in Layer 2 Virtual Private
        Networks (L2VPNs)", RFC6074, January 2011.

   [P2MP-PW-REQ]   F. Jounay, et. al, "Requirements for Point
        to Multipoint Pseudowire",
        draft-ietf-pwe3-p2mp-pw-requirements-03.txt, Work in Progress,
        August 2010.

   [P2MP-LSP-PING] A. Farrel, S. Yasukawa, "Detecting Data Plane
        Failures in Point-to-Multipoint Multiprotocol Label Switching
        (MPLS) - Extensions to LSP Ping",
        draft-ietf-mpls-p2mp-lsp-ping-15.txt, Work In Progress,
        January 2011.












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10. Author's Addresses


   Luca Martini
   Cisco Systems, Inc.
   9155 East Nichols Avenue, Suite 400
   Englewood, CO, 80112
   e-mail: lmartini@cisco.com


   Sami Boutros
   Cisco Systems, Inc.
   170 West Tasman Drive
   San Jose, CA 95134
   e-mail: sboutros@cisco.com


   Siva Sivabalan
   2000 Innovation Drive
   Kanata, ONTARIO K2K 3E8
   CANADA
   e-mail: msiva@cisco.com


   Maciek Konstantynowicz
   Juniper Networks
   UNITED KINGDOM
   e-mail: maciek@juniper.net


   Gianni Del Vecchio
   Swisscom (Schweiz) AG
   Zentweg 9
   CH-3006 Bern
   Switzerland
   e-mail: Gianni.DelVecchio@swisscom.com


   Thomas D. Nadeau
   Huawei Technologies
   2330 Central Expy
   Santa Clara, CA 95050
   USA
   e-mail: thomas.nadeau@huawei.com







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   Frederic Jounay
   France Telecom
   2, avenue Pierre-Marzin
   22307 Lannion Cedex
   FRANCE
   Email: frederic.jounay@orange-ftgroup.com


   Philippe Niger
   France Telecom
   2, avenue Pierre-Marzin
   22307 Lannion Cedex
   FRANCE
   Email: philippe.niger@orange-ftgroup.com


   Yuji Kamite
   NTT Communications Corporation
   Tokyo Opera City Tower
   3-20-2 Nishi Shinjuku, Shinjuku-ku
   Tokyo  163-1421
   Japan
   Email: y.kamite@ntt.com


   Lizhong Jin
   ZTE
   889 Bibo Road,
   Shanghai, 201203
   P.R.China
   Email: lizhong.jin@zte.com.cn


   Martin Vigoureux
   Alcatel-Lucent
   Route de Villejust
   Nozay,   91620
   France
   Email: martin.vigoureux@alcatel-lucent.com


   Laurent Ciavaglia
   Alcatel-Lucent
   Route de Villejust
   Nozay,   91620
   France
   Email: Laurent.Ciavaglia@alcatel-lucent.com



Boutros, et al.                                                [Page 17]

Internet Draft       draft-ietf-pwe3-p2mp-pw-02.txt        March 2, 2011



   Simon Delord
   Alcatel-Lucent

   E-mail: simon.a.delord@team.telstra.com



Copyright Notice

   Copyright (c) 2011 IETF Trust and the persons identified as the
   document authors. All rights reserved.

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   publication of this document. Please review these documents
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   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008. The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
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   it for publication as an RFC or to translate it into languages other
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Acknowledgments

   The authors wish to acknowledge the contributions of Ali Sajassi.

   Expiration Date: September 2011










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