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Internet Engineering Task Force (IETF)                    K. Kumaki, Ed.
Request for Comments: 6882                              KDDI Corporation
Category: Experimental                                          T. Murai
ISSN: 2070-1721                          Furukawa Network Solution Corp.
                                                                D. Cheng
                                                     Huawei Technologies
                                                           S. Matsushima
                                                        Softbank Telecom
                                                                P. Jiang
                                                        KDDI Corporation
                                                              March 2013


Support for Resource Reservation Protocol Traffic Engineering (RSVP-TE)
              in Layer 3 Virtual Private Networks (L3VPNs)

Abstract

   IP Virtual Private Networks (VPNs) provide connectivity between sites
   across an IP/MPLS backbone.  These VPNs can be operated using
   BGP/MPLS, and a single Provider Edge (PE) node may provide access to
   multiple customer sites belonging to different VPNs.

   The VPNs may support a number of customer services, including RSVP
   and Resource Reservation Protocol Traffic Engineering (RSVP-TE)
   traffic.  This document describes how to support RSVP-TE between
   customer sites when a single PE supports multiple VPNs and labels are
   not used to identify VPNs between PEs.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for examination, experimental implementation, and
   evaluation.

   This document defines an Experimental Protocol for the Internet
   community.  This document is a product of the Internet Engineering
   Task Force (IETF).  It represents the consensus of the IETF
   community.  It has received public review and has been approved for
   publication by the Internet Engineering Steering Group (IESG).  Not
   all documents approved by the IESG are a candidate for any level of
   Internet Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6882.





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Copyright Notice

   Copyright (c) 2013 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 Simplified BSD License.

Table of Contents

   1. Introduction ....................................................3
      1.1. Conventions ................................................3
   2. Motivation ......................................................4
      2.1. Network Example ............................................4
   3. Protocol Extensions and Procedures ..............................5
      3.1. Object Definitions .........................................5
           3.1.1. LSP_TUNNEL_VPN-IPv4 and LSP_TUNNEL_VPN-IPv6
                  SESSION Object ......................................6
           3.1.2. LSP_TUNNEL_VPN-IPv4 and LSP_TUNNEL_VPN-IPv6
                  SENDER_TEMPLATE .....................................7
           3.1.3. LSP_TUNNEL_VPN-IPv4 and LSP_TUNNEL_VPN-IPv6
                  FILTER_SPEC Objects .................................9
           3.1.4. VPN-IPv4 and VPN-IPv6 RSVP_HOP Objects ..............9
      3.2. Handling the Messages ......................................9
           3.2.1. Path Message Processing at the Ingress PE ...........9
           3.2.2. Path Message Processing at the Egress PE ...........10
           3.2.3. Resv Processing at the Egress PE ...................11
           3.2.4. Resv Processing at the Ingress PE ..................11
           3.2.5. Other RSVP Messages ................................12
   4. Management Considerations ......................................12
      4.1. Impact on Network Operation ...............................12
   5. Security Considerations ........................................13
   6. References .....................................................13
      6.1. Normative References ......................................13
      6.2. Informative References ....................................13
   7. Acknowledgments ................................................14
   8. Contributors ...................................................14







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1.  Introduction

   Service Providers would like to use BGP/MPLS IP VPNs [RFC4364] to
   support connections between Customer Edge (CE) sites.  As described
   in [RFC5824], these connections can be MPLS Traffic Engineered (TE)
   Label Switched Paths (LSPs) established using extensions to RSVP
   [RFC3209] for a number of different deployment scenarios.  The
   requirements for supporting MPLS-TE LSP connections across BGP/MPLS
   IP VPNs are documented in [RFC5824].

   In order to establish a customer MPLS-TE LSP over a BGP/MPLS IP VPN,
   it is necessary for the RSVP-TE control messages, including the Path
   and Resv messages described in [RFC3209], to be handled appropriately
   by the Provider Edge (PE) routers.  [RFC4364] allows RSVP messages
   sent within a VPN's context to be handled just like any other VPN
   data.  In such a solution, the RSVP-TE component at a PE that sends
   messages toward a remote PE must process the messages in the context
   of the VPN and must ensure that the messages are correctly labeled.
   Similarly, when a message sent across the core is received by a PE,
   both labels must indicate the correct VPN context.

   Implementation of the standards-based solution described in the
   previous paragraph is possible, but requires proper support on the
   PE.  In particular, a PE must be able to process RSVP messages within
   the context of the appropriate VPN Routing and Forwarding (VRF).
   This may be easy to achieve in some implementations, but in others,
   it is not so easy.

   This document defines experimental formats and mechanisms that follow
   a different approach.  The documented approach enables the VPN
   identifier to be carried in the RSVP-TE protocol message so that
   there is no requirement for label-based VRF identification on the PE.

   The experiment proposed by this document does not negate the label-
   based approach supported by [RFC4364].  The experiment is intended to
   enable research into alternate methods of supporting RSVP-TE within
   VPNs.

1.1.  Conventions

   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 RFC 2119 [RFC2119].








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2.  Motivation

   If multiple BGP/MPLS IP VPNs are supported at the same PE, new RSVP-
   TE extensions are required so that RSVP-TE control messages from the
   CEs can be handled appropriately by the PE.

2.1.  Network Example

   Figure 1 ("Customer MPLS TE LSPs in the context of BGP/MPLS IP VPNs")
   shows two VPNs supported by a core IP/MPLS network.  Both VPNs have
   customer sites on the two PEs shown in the figure.  The customer
   sites operate MPLS-TE LSPs.

   Here, we make the following set of assumptions:

   o  VPN1 and VPN2 are for different customers.
   o  CE1 and CE3 are head-end routers.
   o  CE2 and CE4 are tail-end routers.
   o  The same address (e.g., 192.0.2.1) is assigned at CE2 and CE4.

        <--------Customer MPLS-TE LSP for VPN1-------->

      .......                                        .......
      . --- .    ---      ---       ---      ---     . --- .
      .|CE1|----|PE1|----|P1 |-----|P2 |----|PE2|-----|CE2|.
      . --- .    ---      ---       ---      ---     . --- .
      .......     |                           |      .......
      (VPN1)      |                           |      (VPN1)
                  |                           |
      .......     |                           |      .......
      . --- .     |                           |      . --- .
      .|CE3|------+                           +-------|CE4|.
      . --- .                                        . --- .
      .......                                        .......
      (VPN2)                                         (VPN2)

        <--------Customer MPLS-TE LSP for VPN2-------->
                  ^                           ^
                  |                           |
             VRF instance                VRF instance

      <-Customer->    <---BGP/MPLS IP VPN--->   <-Customer->
         network                                   network

      Figure 1: Customer MPLS TE LSPs in the context of BGP/MPLS IP VPNs






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      Consider that customers in VPN1 and VPN2 would like to establish
      customer MPLS-TE LSPs between their sites (i.e., between CE1 and
      CE2, and between CE3 and CE4).  In this situation, the following
      RSVP-TE Path messages would be sent:

      1. CE1 would send a Path message to PE1 to establish the MPLS-TE
         LSP (VPN1) between CE1 and CE2.

      2. CE3 would also send a Path message to PE1 to establish the
         MPLS-TE LSP (VPN2) between CE1 and CE2.

   After receiving each Path message, PE1 can identify the customer
   context for each Path message from the incoming interface over which
   the message was received.  PE1 forwards the messages to PE2 using the
   routing mechanisms described in [RFC4364] and [RFC4659].

   When the Path messages are received at PE2, that node needs to
   distinguish the messages and determine which applies to VPN1 and
   which to VPN2 so that the right forwarding state can be established
   and so that the messages can be passed on to the correct CE.
   Although the messages arrive at PE2 with an MPLS label that
   identifies the VPN, the messages are delivered to the RSVP-TE
   component on PE2, and the context of the core VPN LSP (i.e., the
   label) is lost.  Some RSVP-TE protocol mechanism is therefore needed
   to embed the VPN identifier within the RSVP-TE message.

   Similarly, Resv messages sent from PE2 to PE1 need an RSVP-TE
   mechanism to assign them to the correct VPN.

3.  Protocol Extensions and Procedures

   This section defines the additional RSVP-TE objects to meet the
   requirements described in Section 2.  These objects are new variants
   of the SESSION, SENDER_TEMPLATE, and FILTERSPEC objects.  They act as
   identifiers and allow PEs to distinguish Path/Resv messages per VPN
   in the context of BGP/MPLS IP VPNs.  Section 3.1 defines the new
   object types, and Section 3.2 defines the specific procedures for
   handling RSVP messages.

3.1.  Object Definitions

   This experiment will be carried out using the following private Class
   Types.  This document identifies these Class Types as
   "C-Type = EXPn".







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   Class = SESSION, LSP_TUNNEL_VPN-IPv4 C-Type = EXP1
   Class = SESSION, LSP_TUNNEL_VPN-IPv6 C-Type = EXP2
   Class = SENDER_TEMPLATE, LSP_TUNNEL_VPN-IPv4 C-Type = EXP3
   Class = SENDER_TEMPLATE, LSP_TUNNEL_VPN-IPv6 C-Type = EXP4
   Class = FILTER SPECIFICATION, LSP_TUNNEL_VPN-IPv4 C-Type = EXP5
   Class = FILTER SPECIFICATION, LSP_TUNNEL_VPN-IPv6 C-Type = EXP6

3.1.1.  LSP_TUNNEL_VPN-IPv4 and LSP_TUNNEL_VPN-IPv6 SESSION Object

   The LSP_TUNNEL_VPN-IPv4 (or LSP_TUNNEL_VPN-IPv6) SESSION object
   appears in RSVP-TE messages that ordinarily contain a SESSION object
   and that are sent between the ingress PE and egress PE in either
   direction.  This object MUST NOT be included in any RSVP-TE message
   that is sent outside of the provider's backbone.

   The LSP_TUNNEL_VPN-IPv6 SESSION object is analogous to the
   LSP_TUNNEL_VPN-IPv4 SESSION object, using a VPN-IPv6 address
   ([RFC4659]) instead of a VPN-IPv4 address ([RFC4364]).

   Experimenters MUST ensure that there is no conflict between the
   private Class Types used for this experiment and other Class Types
   used by the PEs.

   The formats of the SESSION objects are as follows:

     Class = SESSION, LSP_TUNNEL_VPN-IPv4 C-Type = EXP1

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                                                               +
   |            VPN-IPv4 Tunnel Endpoint Address (12 bytes)        |
   +                                                               +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  MUST be zero                 |      Tunnel ID                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Extended Tunnel ID                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+











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     Class = SESSION, LSP_TUNNEL_VPN-IPv6 C-Type = EXP2

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                                                               +
   |                                                               |
   +                                                               +
   |                                                               |
   +       VPN-IPv6 Tunnel Endpoint Address (24 bytes)             +
   |                                                               |
   +                                                               +
   |                                                               |
   +                                                               +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  MUST be zero                 |      Tunnel ID                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                                                               +
   |                                                               |
   +                  Extended Tunnel ID (16 bytes)                +
   |                                                               |
   +                                                               +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The VPN-IPv4 or VPN-IPv6 tunnel endpoint address field contains an
   address of the VPN-IPv4 or VPN-IPv6 address family encoded as
   specified in [RFC4364] or [RFC4659], respectively.

   The Tunnel ID and Extended Tunnel ID are identical to the same fields
   in the LSP_TUNNEL_IPv4 and LSP_TUNNEL_IPv6 SESSION objects as per
   [RFC3209].

3.1.2.  LSP_TUNNEL_VPN-IPv4 and LSP_TUNNEL_VPN-IPv6 SENDER_TEMPLATE
        Objects

   The LSP_TUNNEL_VPN-IPv4 (or LSP_TUNNEL_VPN-IPv6) SENDER_TEMPLATE
   object appears in RSVP-TE messages that ordinarily contain a
   SENDER_TEMPLATE object and that are sent between ingress PE and
   egress PE in either direction, such as Path, PathError, and PathTear
   messages.  The object MUST NOT be included in any RSVP-TE messages
   that are sent outside of the provider's backbone.






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   The format of the object is as follows:

     Class = SENDER_TEMPLATE, LSP_TUNNEL_VPN-IPv4 C-Type = EXP3

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                                                               +
   |            VPN-IPv4 Tunnel Sender Address (12 bytes)          |
   +                                                               +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  MUST be zero                 |            LSP ID             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     Class = SENDER_TEMPLATE, LSP_TUNNEL_VPN-IPv6 C-Type = EXP4

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                                                               +
   |                                                               |
   +                                                               +
   |                                                               |
   +         VPN-IPv6 Tunnel Sender Address (24 bytes)             +
   |                                                               |
   +                                                               +
   |                                                               |
   +                                                               +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  MUST be zero                 |            LSP ID             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The VPN-IPv4 or VPN-IPv6 tunnel sender address field contains an
   address of the VPN-IPv4 or VPN-IPv6 address family encoded as
   specified in [RFC4364] or [RFC4659], respectively.

   The LSP ID is identical to the LSP ID field in the LSP_TUNNEL_IPv4
   and LSP_TUNNEL_IPv6 SENDER_TEMPLATE objects as per [RFC3209].









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3.1.3.  LSP_TUNNEL_VPN-IPv4 and LSP_TUNNEL_VPN-IPv6 FILTER_SPEC Objects

   The LSP_TUNNEL_VPN-IPv4 (or LSP_TUNNEL_VPN-IPv6) FILTER_SPEC object
   appears in RSVP-TE messages that ordinarily contain a FILTER_SPEC
   object and that are sent between ingress PE and egress PE in either
   direction, such as Resv, ResvError, and ResvTear messages.  The
   object MUST NOT be included in any RSVP-TE messages that are sent
   outside of the provider's backbone.

   Class = FILTER SPECIFICATION, LSP_TUNNEL_VPN-IPv4 C-Type = EXP5

      The format of the LSP_TUNNEL_VPN-IPv4 FILTER_SPEC object is
      identical to the LSP_TUNNEL_VPN-IPv4 SENDER_TEMPLATE object.

   Class = FILTER SPECIFICATION, LSP_TUNNEL_VPN-IPv6 C-Type = EXP6

      The format of the LSP_TUNNEL_VPN-IPv6 FILTER_SPEC object is
      identical to the LSP_TUNNEL_VPN-IPv6 SENDER_TEMPLATE object.

3.1.4.  VPN-IPv4 and VPN-IPv6 RSVP_HOP Objects

   The formats of the VPN-IPv4 and VPN-IPv6 RSVP_HOP objects are
   identical to the RSVP_HOP objects described in [RFC6016].

3.2.  Handling the Messages

   This section describes how the RSVP-TE messages are handled.
   Handling of these messages assumes that, in the context of BGP/MPLS
   IP VPNs, the ingress and egress PEs have RSVP-TE capabilities.

3.2.1.  Path Message Processing at the Ingress PE

   When a Path message arrives at the ingress PE (PE1 in Figure 1), the
   PE needs to establish suitable Path state and forward the Path
   message on to the egress PE (PE2 in Figure 1).  Below, we describe
   the message handling process at the ingress PE.

      1. CE1 sends a Path message to PE1 to establish the MPLS-TE LSP
         (VPN1) between CE1 and CE2.  The Path message is addressed to
         the eventual destination (the receiver at the remote customer
         site) and carries the IP Router Alert option, in accordance
         with [RFC2205].  The ingress PE must recognize the router
         alert, intercept these messages, and process them as RSVP-TE
         signaling messages.







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      2. When the ingress PE receives a Path message from a CE that is
         addressed to the receiver, the VRF that is associated with the
         incoming interface can be identified.  (This step does not
         deviate from current behavior.)

      3. The tunnel endpoint address of the receiver is looked up in the
         appropriate VRF, and the BGP next hop for that tunnel endpoint
         address is identified.  The next hop is the egress PE.

      4. A new LSP_TUNNEL_VPN-IPv4/VPN-IPv6 SESSION object is
         constructed, containing the Route Distinguisher (RD) that is
         part of the VPN-IPv4/VPN-IPv6 route prefix for this tunnel
         endpoint address, and the IPv4/IPv6 tunnel endpoint address
         from the original SESSION object.

      5. A new LSP_TUNNEL_VPN-IPv4/IPv6 SENDER_TEMPLATE object is
         constructed, with the original IPv4/IPv6 tunnel sender address
         from the incoming SENDER_TEMPLATE plus the RD that is used by
         the PE to advertise the prefix for the customers VPN.

      6. A new Path message is sent containing all the objects from the
         original Path message, replacing the original SESSION and
         SENDER_TEMPLATE objects with the new
         LSP_TUNNEL_VPN-IPv4/VPN-IPv6 type objects.  This Path message
         is sent directly to the egress PE (the next hop that was
         determined in Step 3) without the IP Router Alert option.

3.2.2.  Path Message Processing at the Egress PE

   Below, we describe the message handling process at the egress PE.

      1. When a Path message arrives at the egress PE (PE2 in Figure 1),
         it is addressed to the PE itself and is handed to RSVP for
         processing.

      2. The router extracts the RD and IPv4/IPv6 address from the
         LSP_TUNNEL_VPN-IPv4/VPN-IPv6 SESSION object and determines the
         local VRF context by finding a matching VPN-IPv4 prefix with
         the specified RD that has been advertised by this router into
         BGP.

      3. The entire incoming RSVP message, including the VRF
         information, is stored as part of the Path state.








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      4. The egress PE can now construct a Path message that differs
         from the Path message it received in the following ways:

         a. Its tunnel endpoint address is the IP address extracted from
            the SESSION object.

         b. The SESSION and SENDER_TEMPLATE objects have been converted
            back to IPv4-type/IPv6-type by discarding the attached RD.

         c. The RSVP_HOP object contains the IP address of the outgoing
            interface of the egress PE and a Logical Interface Handle
            (LIH), as per normal RSVP processing.

      5. The egress PE then sends the Path message towards its tunnel
         endpoint address over the interface identified in Step 4c.
         This Path message carries the IP Router Alert option, as
         required by [RFC2205].

3.2.3.  Resv Processing at the Egress PE

   When a receiver at the customer site originates a Resv message for
   the session, normal RSVP procedures apply until the Resv, making its
   way back towards the sender, arrives at the "egress" PE (it is the
   egress with respect to the direction of data flow, i.e., PE2 in
   Figure 1).  Upon arriving at PE2, the SESSION and FILTER_SPEC objects
   in the Resv message, and the VRF in which the Resv was received, are
   used to find the matching Path state that was stored previously.

   The PE constructs a Resv message to send to the RSVP HOP stored in
   the Path state, i.e., the ingress PE (PE1 in Figure 1).  The LSP
   TUNNEL IPv4/IPv6 SESSION object is replaced with the same
   LSP_TUNNEL_VPN-IPv4/VPN-IPv6 SESSION object received in the Path
   message.  The LSP TUNNEL IPv4/IPv6 FILTER_SPEC object is replaced
   with a LSP_TUNNEL_VPN-IPv4/VPN-IPv6 FILTER_SPEC object, which copies
   the VPN-IPv4/VPN-IPv6 address from the LSP TUNNEL SENDER_TEMPLATE
   received in the matching Path message.

   The Resv message MUST be addressed to the IP address contained within
   the RSVP_HOP object in the Path message.

3.2.4.  Resv Processing at the Ingress PE

   When the ingress PE receives a Resv message (the ingress with respect
   to data flow, i.e., PE1 in Figure 1), the PE determines the local VRF
   context and associated Path state for this Resv message by decoding
   the received SESSION and FILTER_SPEC objects.  It is now possible to
   generate a Resv message to send to the appropriate CE.  The Resv




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   message sent to the ingress CE contains the LSP TUNNEL IPv4/IPv6
   SESSION and LSP TUNNEL FILTER_SPEC objects, which are derived from
   the appropriate Path state.

3.2.5.  Other RSVP Messages

   Processing of other RSVP messages (i.e., PathError, PathTear,
   ResvError, ResvTear, and ResvConf) generally follows the rules
   defined in [RFC2205].  The following additional rules MUST be
   observed for messages transmitted within the VPN, i.e., between the
   PEs:

   o  The SESSION, SENDER_TEMPLATE, and FILTER_SPEC objects MUST be
      converted from LSP_TUNNEL_IPv4/LSP_TUNNEL_IPv6 [RFC3209] to
      LSP_TUNNEL_VPN-IPv4/LSP_TUNNEL_VPN-IPv6 form, respectively, and
      back again, in the same manner as described above for Path and
      Resv messages.

   o  The appropriate type of RSVP_HOP object (VPN-IPv4 or VPN-IPv6)
      MUST be used, as described in Section 8.4 of [RFC6016].

   o  Depending on the type of RSVP_HOP object received from the
      neighbor, the message MUST be MPLS encapsulated or IP
      encapsulated.

   o  The matching state and VRF MUST be determined by decoding the
      corresponding RD and IPv4 or IPv6 address in the SESSION and
      FILTER_SPEC objects.

   o  The message MUST be directly addressed to the appropriate PE,
      without using the Router Alert Option.

4.  Management Considerations

   MPLS-TE-based BGP/MPLS IP VPNs are based on a peer model.  If an
   operator would like to configure a new site to an existing VPN,
   configuration of both the CE router and the attached PE router is
   required.  The operator is not required to modify the configuration
   of PE routers connected to other sites or to modify the configuration
   of other VPNs.

4.1.  Impact on Network Operation

   It is expected that the use of the extensions specified in this
   document will not significantly increase the level of operational
   traffic.





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   Furthermore, the additional extensions described in this document
   will have no impact on the operation of existing resiliency
   mechanisms available within MPLS-TE.

5.  Security Considerations

   This document defines RSVP-TE extensions for BGP/MPLS IP VPNs.  The
   general security issues for RSVP-TE are described in [RFC3209],
   [RFC4364] addresses the specific security considerations of BGP/MPLS
   VPNs.  General security considerations for MPLS are described in
   [RFC5920].

   In order to secure the control plane, techniques such as the TCP
   Authentication Option (TCP-AO) [RFC5925] MAY be used authenticate BGP
   messages.

   To ensure the integrity of an RSVP request, the RSVP Authentication
   mechanisms defined in [RFC2747], and updated by [RFC3097], SHOULD be
   used.

6.  References

6.1.  Normative References

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

   [RFC3209]  Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
              and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
              Tunnels", RFC 3209, December 2001.

6.2.  Informative References

   [RFC2205]  Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
              Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
              Functional Specification", RFC 2205, September 1997.

   [RFC2747]  Baker, F., Lindell, B., and M. Talwar, "RSVP Cryptographic
              Authentication", RFC 2747, January 2000.

   [RFC3097]  Braden, R. and L. Zhang, "RSVP Cryptographic
              Authentication -- Updated Message Type Value", RFC 3097,
              April 2001.

   [RFC4364]  Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
              Networks (VPNs)", RFC 4364, February 2006.





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RFC 6882              Support for RSVP-TE in L3VPNs           March 2013


   [RFC4659]  De Clercq, J., Ooms, D., Carugi, M., and F. Le Faucheur,
              "BGP-MPLS IP Virtual Private Network (VPN) Extension for
              IPv6 VPN", RFC 4659, September 2006.

   [RFC5824]  Kumaki, K., Ed., Zhang, R., and Y. Kamite, "Requirements
              for Supporting Customer Resource ReSerVation Protocol
              (RSVP) and RSVP Traffic Engineering (RSVP-TE) over a
              BGP/MPLS IP-VPN", RFC 5824, April 2010.

   [RFC5920]  Fang, L., Ed., "Security Framework for MPLS and GMPLS
              Networks", RFC 5920, July 2010.

   [RFC5925]  Touch, J., Mankin, A., and R. Bonica, "The TCP
              Authentication Option", RFC 5925, June 2010.

   [RFC6016]  Davie, B., Le Faucheur, F., and A. Narayanan, "Support for
              the Resource Reservation Protocol (RSVP) in Layer 3 VPNs",
              RFC 6016, October 2010.

7.  Acknowledgments

   The authors would like to express thanks to Makoto Nakamura and
   Daniel King for their helpful and useful comments and feedback.

8.  Contributors

   Chikara Sasaki
   KDDI R&D Laboratories, Inc.
   2-1-15 Ohara Fujimino
   Saitama 356-8502
   Japan
   EMail: ch-sasaki@kddilabs.jp


   Daisuke Tatsumi
   KDDI Corporation
   2-3-2 Nishishinjuku Shinjuku-ku
   Tokyo 163-8003
   Japan
   EMail: da-tatsumi@kddi.com











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RFC 6882              Support for RSVP-TE in L3VPNs           March 2013


Authors' Addresses

   Kenji Kumaki
   KDDI Corporation
   Garden Air Tower
   Iidabashi, Chiyoda-ku,
   Tokyo 102-8460
   Japan
   EMail: ke-kumaki@kddi.com


   Tomoki Murai
   Furukawa Network Solution Corp.
   5-1-9, Higashi-Yawata, Hiratsuka
   Kanagawa 254-0016
   Japan
   EMail: murai@fnsc.co.jp


   Dean Cheng
   Huawei Technologies
   2330 Central Expressway
   Santa Clara, CA 95050
   USA
   EMail: dean.cheng@huawei.com


   Satoru Matsushima
   Softbank Telecom
   1-9-1,Higashi-Shimbashi,Minato-Ku
   Tokyo 105-7322
   Japan
   EMail: satoru.matsushima@g.softbank.co.jp


   Peng Jiang
   KDDI Corporation
   Garden Air Tower
   Iidabashi, Chiyoda-ku,
   Tokyo 102-8460
   Japan
   EMail: pe-jiang@kddi.com









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