Network Working Group                                            J. Dong
Internet-Draft                                                   M. Chen
Intended status: Standards Track                     Huawei Technologies
Expires: November 8, 2015 June 5, 2016                                         H. Gredler
                                                  Juniper Networks, Inc.
                                                  Individual Contributor
                                                              S. Previdi
                                                     Cisco Systems, Inc.
                                                             J. Tantsura
                                                                Ericsson
                                                             May 7,
                                                        December 3, 2015

   Distribution of MPLS Traffic Engineering (TE) LSP State using BGP
                 draft-ietf-idr-te-lsp-distribution-03
                 draft-ietf-idr-te-lsp-distribution-04

Abstract

   This document describes a mechanism to collect the Traffic
   Engineering (TE) LSP information using BGP.  Such information can be
   used by external components for path reoptimization, service
   placement
   placement, and network visualization.

Requirements Language

   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].

Status of This Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
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   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
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   This Internet-Draft will expire on November 8, 2015. June 5, 2016.

Copyright Notice

   Copyright (c) 2015 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
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   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Carrying LSP State Information in BGP . . . . . . . . . . . .   4
     2.1.  MPLS TE LSP Identifier Information . . . . . . . . . . . . . . . . .   4
     2.2.  IPv4/IPv6 MPLS TE LSP NLRI  . . . . . . . . . . . . . . .   5
       2.2.1.  MPLS TE LSP Descriptors . . . . . . . . . . . . . . .   6
     2.3.  LSP State Information . . . . . . . . . . . . . . . . . .   6   8
       2.3.1.  RSVP Objects  . . . . . . . . . . . . . . . . . . . .  10
       2.3.2.  PCE Objects . . . . . . . . . . . . . . . . . . . . .  11
       2.3.3.  SR Encap TLVs . . . . . . . . . . . . . . . . . . . .  11
   3.  Operational Considerations  . . . . . . . . . . . . . . . . .   7  12
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8  12
     4.1.  BGP-LS NLRI-Types . . . . . . . . . . . . . . . . . . . .   8  12
     4.2.  BGP-LS Protocol-IDs . . . . . . . . . . . . . . . . . . .   8  12
     4.3.  BGP-LS Instance-IDs . . Descriptors TLVs . . . . . . . . . . . . . . . . .   9  13
     4.4.  BGP-LS Attribute TLVs . . . . . . . . LSP-State TLV Protocol Origin  . . . . . . . . . .   9  13
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   9  14
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   9  14
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   9  14
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .   9  14
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  11  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11  16

1.  Introduction

   In some network environments, the states state of established Multi-
   Protocol Multi-Protocol
   Label Switching (MPLS) Traffic Engineering (TE) Label Switched Paths
   (LSPs) and Tunnels in the network are required by some components external
   to the network domain.  Usually this information is directly
   maintained by the ingress Label Edge Routers (LERs) of the MPLS TE
   LSPs.

   One example of using the LSP information is stateful Path Computation
   Element (PCE) [I-D.ietf-pce-stateful-pce], which could provide
   benefits in path reoptimization . reoptimization.  While some extensions are proposed
   in Path Computation Element Communication Protocol (PCEP) for the
   Path Computation Clients (PCCs) to report the LSP states to the PCE,
   this mechanism may not be applicable in a management-based PCE
   architecture as specified in section 5.5 of [RFC4655].  As
   illustrated in the figure below, the PCC is not an LSR in the routing
   domain, thus the head-end nodes of the TE-LSP TE-LSPs may not implement the
   PCEP protocol.  In this case some a general mechanism to collect the
   TE-LSP TE-
   LSP states from the ingress LERs is needed.  This document proposes
   an LSP state collection mechanism complementary to the mechanism
   defined in [I-D.ietf-pce-stateful-pce].

                                   -----------
                                  |   -----   |
              Service             |  | TED |<-+----------->
              Request             |   -----   |  TED synchronization
                 |                |     |     |  mechanism (for example,
                 v                |     |     |  routing protocol)
           ------------- Request/ |     v     |
          |             | Response|   -----   |
          |     NMS     |<--------+> | PCE |  |
          |             |         |   -----   |
           -------------           -----------
         Service |
         Request |
                 v
            ----------  Signaling   ----------
           | Head-End | Protocol   | Adjacent |
           |  Node    |<---------->|   Node   |
            ----------              ----------

                 Figure 1.  Management-Based PCE Usage

   In networks with composite PCE nodes as specified in section 5.1 of
   [RFC4655], the PCE is implemented on several routers in the network, and
   the PCCs in the network can use the mechanism described in
   [I-D.ietf-pce-stateful-pce] to report the LSP information to the PCE
   nodes.  An external component may further also need to collect the LSP
   information from all the PCEs in the network to get obtain a global view
   of the LSP states state in the network.

   In multi-area or multi-AS scenarios, each area or AS can have a child
   PCE to collect the LSP states of state in its own domain, in addition addition, a parent
   PCE needs to collect the LSP information from multiple child PCEs to
   obtain a global view of LSPs inside and across the domains involved.

   In another network scenario, a centralized controller is used for
   service placement.  Obtaining the TE LSP state information is quite
   important for making appropriate service placement decisions with the
   purpose of to both meeting meet the application's requirements and utilizing
   the utilize
   network resource resources efficiently.

   The Network Management System (NMS) may need to provide global
   visibility of the TE LSPs in the network as part of the network
   visualization function.

   BGP has been extended to distribute link-state and traffic
   engineering information to some external components
   [I-D.ietf-idr-ls-distribution].  Using the same protocol to collect
   other network layer
   TE LSP information would be is desirable for the these external
   components, which components since
   this avoids introducing multiple protocols for network information
   collection.  This document describes a mechanism to distribute the TE LSP
   information to external components using BGP.

2.  Carrying LSP State Information in BGP

2.1.  MPLS TE LSP Identifier Information

   The MPLS TE LSP Identifier information is advertised in BGP UPDATE messages
   using the MP_REACH_NLRI and MP_UNREACH_NLRI attributes [RFC4760].
   The "Link-State NLRI" defined in [I-D.ietf-idr-ls-distribution] is
   extended to carry the MPLS TE LSP
   Identifier information.  BGP speakers that
   wish to exchange MPLS TE LSP information MUST use the BGP
   Multiprotocol Extensions Capability Code (1) to advertise the
   corresponding (AFI, SAFI) pair, as specified in [RFC4760].

   The format of "Link-State NLRI" is defined in
   [I-D.ietf-idr-ls-distribution].  Two  A new "NLRI Type" are is defined for
   MPLS TE LSP Identifier Information as following:

   o  NLRI Type = 5: IPv4 TE LSP NLRI

   o  NLRI Type = 6: IPv6 TE LSP NLRI

   The IPv4 Type: IPv4/IPv6 MPLS TE LSP NLRI (NLRI Type = 5) is shown in (suggested codepoint value
      5, to be assigned by IANA).

   [I-D.ietf-idr-ls-distribution] defines the following
   figure: BGP-LS NLRI 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
     +-+-+-+-+-+-+-+-+
     |  Protocol-ID  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                           Identifier                          |            NLRI Type          |                            (64 bits)     Total NLRI Length         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                   IPv4 Tunnel Sender Address                  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                                                               |             Tunnel ID
     //                  Link-State NLRI (variable)                 //
     |             LSP ID                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                  IPv4 Tunnel End-point Address                |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                       Figure 2. IPv4

   This document defines a new NLRI-Type and its format: the IPv4/IPv6
   MPLS TE LSP NLRI defined in the following section.

2.2.  IPv4/IPv6 MPLS TE LSP NLRI

   The IPv6 IPv4/IPv6 MPLS TE LSP NLRI (NLRI Type = 6) 5.  Suggested value, to be
   assigned by IANA) is shown 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
     +-+-+-+-+-+-+-+-+
     |  Protocol-ID  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                        Identifier                             |
     |                        (64 bits)                              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
     +                                                               +
     |                  IPv6 Tunnel Sender Address                   |
     +                          (16 octets)                          +
     |                                                               |
     +                                                               +
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          Tunnel ID            |             LSP ID            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
     +                                                               +
     |                 IPv6 Tunnel End-point Address                 |
     +                          (16 octets)                          +
     |                                                               |
     +                                                               +
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                       Figure 3. IPv6 TE LSP NLRI

   For IPv4 and IPv6
     //                MPLS TE LSP NLRI, the Descriptors (variable)           //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Protocol-ID field specifies the type of signaling of the MPLS TE
      LSP.  The following Protocol-IDs applies are defined (suggested values, to
      be assigned by IANA) and apply to the IPv4/IPv6 MPLS TE LSP NLRI:

               +-------------+----------------------------------+
               | Protocol-ID | NLRI information source protocol |
               +-------------+----------------------------------+
               |     TBD      7      |   RSVP-TE                        |
               |     TBD      8      |   Segment Routing                |
               +-------------+----------------------------------+

   The 64-Bit 'Identifier' field is used to discriminate between
   instances with different LSP technologies.  The default identifier
   "0" identifies the instance for packet switched LSPs.  A new
   identifier TBD

   o  "Identifier" is used to identify the instance of optical layer
   LSPs.

   The other fields an 8 octet value as defined in the IPv4 TE LSP NLRI and IPv6
      [I-D.ietf-idr-ls-distribution].

   o  Following MPLS TE LSP NLRI Descriptors are the
   same as defined in [RFC3209].  When the Protocol-ID is set to Segment
   Routing, the defined:

   +-----------+----------------------------------+
   | Codepoint |       Descriptor TLV             |
   +-----------+----------------------------------+
   |  267      | Tunnel ID and                        |
   |  268      | LSP ID field SHOULD be filled with the
   source node's locally generated identifiers which can uniquely
   identify a specific SR LSP.

2.2.  LSP State Information

   The                           |
   |  269      | IPv4/6 Tunnel Head-end address   |
   |  270      | IPv4/6 Tunnel Tail-end address   |
   |  271      | SR-ENCAP Identifier              |
   +-----------+----------------------------------+

2.2.1.  MPLS TE LSP State TLV is used to describe the characteristics of Descriptors

   This sections defines the MPLS TE
   LSPs, which is carried in the optional non-transitive BGP Attribute
   "LINK_STATE Attribute" defined in [I-D.ietf-idr-ls-distribution]. Descriptors TLVs.

2.2.1.1.  Tunnel Identifier (Tunnel ID)

   The "Value" field of the LSP State Tunnel Identifier TLV corresponds to contains the format and
   semantics of a set of objects Tunnel ID defined in [RFC3209], [RFC3473] [RFC3209]
   and
   other extensions for TE LSPs.  Rather than replicating all RSVP-TE
   related objects in this document, has the semantics 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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |             Type              |          Length               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |         Tunnel ID             |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Type: To be assigned by IANA (suggested value: 267)

   o  Length: 2 octets.

   o  Tunnel ID: 2 octets as defined in [RFC3209].

2.2.1.2.  LSP Identifier (LSP ID)

   The LSP Identifier TLV contains the LSP ID defined in [RFC3209] and
   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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |             Type              |          Length               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |         LSP ID                |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Type: To be assigned by IANA (suggested value: 268)

   o  Length: 2 octets.

   o  LSP ID: 2 octets as defined in [RFC3209].

2.2.1.3.  IPv4/IPv6 Tunnel Head-End Address

   The IPv4/IPv6 Tunnel Head-End Address TLV contains the Tunnel Head-
   End Address defined in [RFC3209] and has 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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |             Type              |          Length               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //        IPv4/IPv6 Tunnel Head-End Address (variable)         //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Type: To be assigned by IANA (suggested value: 269)

   o  Length: 4 or 16 octets.

   When the IPv4/IPv6 Tunnel Head-end Address TLV contains an IPv4
   address, its length is 4 (octets).

   When the IPv4/IPv6 Tunnel Head-end Address TLV contains an IPv6
   address, its length is 16 (octets).

2.2.1.4.  IPv4/IPv6 Tunnel Tail-End Address

   The IPv4/IPv6 Tunnel Tail-End Address TLV contains the Tunnel Tail-
   End Address defined in [RFC3209] and has 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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |             Type              |          Length               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //        IPv4/IPv6 Tunnel Tail-End Address (variable)         //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Type: To be assigned by IANA (suggested value: 270)

   o  Length: 4 or 16 octets.

   When the IPv4/IPv6 Tunnel Tail-end Address TLV contains an IPv4
   address, its length is 4 (octets).

   When the IPv4/IPv6 Tunnel Tail-end Address TLV contains an IPv6
   address, its length is 16 (octets).

2.2.1.5.  SR-Encap TLV

   The SR-ENCAP TLV contains the Identifier defined in
   [I-D.sreekantiah-idr-segment-routing-te] and 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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |             Type              |          Length               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                        SR-ENCAP Identifier                    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Type: To be assigned by IANA (suggested value: 271)

   o  Length: 4 octets.

   o  SR-ENCAP Identifier: 4 octets as defined in
      [I-D.sreekantiah-idr-segment-routing-te].

2.3.  LSP State Information

   A new TLV called "LSP State TLV" (codepoint to be assigned by IANA),
   is used to describe the characteristics of the MPLS TE LSPs, which is
   carried in the optional non-transitive BGP Attribute "LINK_STATE
   Attribute" defined in [I-D.ietf-idr-ls-distribution].  These MPLS TE
   LSP characteristics include the switching technology of the LSP,
   Quality of Service (QoS) parameters, route information, the
   protection mechanisms, etc.

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |              Type             |             Length            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
     //               LSP State Information (variable)              //
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                               LSP State TLV

   Type: Suggested value 1158 (to be assigned by IANA)

   LSP State Information: Consists of a set of TE-LSP objects as defined
   in [RFC3209],[RFC3473] and [RFC5440].  Rather than replicating all
   MPLS TE LSP related objects in this document, the semantics and
   encodings of the
   existing MPLS TE LSP objects are re-used.  Hence all reused.  These MPLS TE LSP
   objects are
   regarded as sub-TLVs.  The LSP carried in the "LSP State TLV SHOULD only be used Information" with
   IPv4/IPv6 TE LSP NLRI. 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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              Type
     |Protocol-Origin|   Reserved    |             Length            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
   ~
     //           Protocol specific TE-LSP object                   //
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                           LSP State Information

   The Protocol-Origin field identifies the protocol from which the
   contained MPLS TE LSP Objects (variable)                       ~ object originated.  This allows for MPLS TE LSP
   objects defined in different protocols to be collected while avoiding
   the possible code collisions among these protocols.  Three Protocol-
   Origins are defined in this document (suggested values, to be
   assigned by IANA)

               +----------+--------------+
               | Protocol |  LSP Object  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                   Figure 4.
               |  Origin  |   Origin     |
               +----------+--------------+
               |    1     |  RSVP-TE     |
               |    2     |  PCE         |
               |    3     |  SR ENCAP    |
               +----------+--------------+

   The 8-bit Reserved field SHOULD be set to 0 on transmission and
   ignored on receipt.

   The Length field is set to the Length of the value field, which is
   the total length of the contained MPLS TE LSP object.

   The Valued field is a MPLS-TE LSP object which is defined in the
   protocol identified by the Protocol-Origin field.

2.3.1.  RSVP Objects

   RSVP-TE objects are encoded in the "Value" field of the LSP State TLV

   Currently
   and consists of MPLS TE LSP objects defined in RSVP-TE [RFC3209]
   [RFC3473].  Rather than replicating all MPLS TE LSP related objects
   in this document, the semantics and encodings of the MPLS TE LSP Objects that can be
   objects are re-used.  These MPLS TE LSP objects are carried in the
   LSP State TLV
   include: TLV.

   When carrying RSVP-TE objects, the "Protocol-Origin" field is set to
   "RSVP-TE" (suggested value 1, to be assigned by IANA).

   The following RSVP-TE Objects are defined:

   o  SENDER_TSPEC and FLOW_SPEC [RFC2205]

   o  SESSION_ATTRIBUTE [RFC3209]

   o  Explicit Route  EXPLICIT_ROUTE Object (ERO) [RFC3209]

   o  Record Route  ROUTE_RECORD Object (RRO) [RFC3209]

   o  FAST_REROUTE Object [RFC4090]

   o  DETOUR Object [RFC4090]

   o  EXCLUDE_ROUTE Object (XRO) [RFC4874]

   o  SECONDARY_EXPLICIT_ROUTE Object (SERO) [RFC4873]

   o  SECONDARY_RECORD_ROUTE (SRRO) [RFC4873]

   o  LSP_ATTRIBUTES Object [RFC5420]

   o  LSP_REQUIRED_ATTRIBUTES Object [RFC5420]

   o  PROTECTION Object [RFC3473][RFC4872][RFC4873]

   o  ASSOCIATION Object [RFC4872]

   o  PRIMARY_PATH_ROUTE Object [RFC4872]

   o  ADMIN_STATUS Object [RFC3473]

   o  BANDWIDTH  LABEL_REQUEST Object [RFC5440] [RFC3209][RFC3473]

   For the MPLS TE LSP Objects listed above, the corresponding sub-
   objects are also applicable to this mechanism.  Note that this list
   is not exhaustive, other MPLS TE LSP objects which reflect specific
   characteristics of the MPLS TE LSP can also be carried in the LSP
   state TLV.

2.3.2.  PCE Objects

   PCE objects are encoded in the "Value" field of the MPLS TE LSP State
   TLV and consists of PCE objects defined in [RFC5440].  Rather than
   replicating all MPLS TE LSP related objects in this document, the
   semantics and encodings of the MPLS TE LSP objects are re-used.
   These MPLS TE LSP objects are carried in the LSP State TLV.

   When carrying PCE objects, the "Protocol-Origin" field is set to
   "PCE" (suggested value 2, to be assigned by IANA).

   The following PCE Objects are defined:

   o  METRIC Object [RFC5440]

   o  BANDWIDTH Object [RFC5440]

   For the MPLS TE LSP Objects listed above, the corresponding sub-
   objects are also applicable to this mechanism.  Note that this list
   is not exhaustive, other MPLS TE LSP objects which reflect specific
   characteristics of the MPLS TE LSP can also be carried in the LSP
   state TLV.

2.3.3.  SR Encap TLVs

   SR-ENCAP objects are encoded in the "Value" field of the LSP State
   TLV and consists of SR-ENCAP objects defined in
   [I-D.sreekantiah-idr-segment-routing-te].  Rather than replicating
   all MPLS TE LSP related objects in this document, the semantics and
   encodings of the MPLS TE LSP objects are re-used.  These MPLS TE LSP
   objects are carried in the LSP State TLV.

   When carrying SR-ENCAP objects, the "Protocol-Origin" field is set to
   "SR-ENCAP" (suggested value 3, to be assigned by IANA).

   The following SR-ENCAP Objects are defined:

   o  ERO TLV [I-D.sreekantiah-idr-segment-routing-te]

   o  Weight TLV [I-D.sreekantiah-idr-segment-routing-te]

   o  Binding SID TLV [I-D.sreekantiah-idr-segment-routing-te]
   For the MPLS TE LSP Objects listed above, the corresponding subobjects sub-
   objects are also applicable to this mechanism.  Other  Note that this list
   is not exhaustive, other MPLS TE LSP objects which reflect specific states or attributes
   characteristics of the MPLS TE LSP may can also be carried in the LSP
   state TLV, which is for further study. TLV.

3.  Operational Considerations

   The Existing BGP operational procedures apply to this document.  No
   new operation procedures are defined in this document.  The
   operational considerations as specified in
   [I-D.ietf-idr-ls-distribution] apply to this document.

   In general the ingress nodes of the MPLS TE LSPs are responsible for
   the distribution of LSP state information, while other nodes on the
   LSP path may MAY report the LSP information if needed, e.g. when needed.  For example,
   the border routers in the inter-domain case, where case will also distribute LSP
   state information since the ingress node may not have the complete
   information of for the end-to-end path.

4.  IANA Considerations

   IANA is requested to administer the assignment of new values defined
   in this

   This document and summarized in this section.

   IANA needs to assign one requires new TLV type for "LSP State TLV" from the
   registry of BGP-LS Attribute TLVs. IANA assigned codepoints.

4.1.  BGP-LS NLRI-Types

   IANA maintains a registry called "Border Gateway Protocol - Link
   State (BGP-LS) Parameters" with a sub-registry called "BGP-LS NLRI-
   Types".

   IANA

   The following codepoints is requested to assign two new NLRI-Types:

    +------+---------------------------+---------------+ suggested (to be assigned by IANA):

    +------+----------------------------+---------------+
    | Type | NLRI Type                  |   Reference   |
    +------+---------------------------+---------------+
    +------+----------------------------+---------------+
    |  5   | IPv4 TE LSP NLRI          | this document |
    |  6   | IPv6 IPv4/IPv6 MPLS TE LSP NLRI | this document |
    +------+---------------------------+---------------+
    +------+----------------------------+---------------+

4.2.  BGP-LS Protocol-IDs

   IANA maintains a registry called "Border Gateway Protocol - Link
   State (BGP-LS) Parameters" with a sub-registry called "BGP-LS
   Protocol-IDs".

   IANA is requested to assign two new Protocol-IDs:

   The following Protocol-ID codepoints are suggested (to be assigned by
   IANA):

    +-------------+----------------------------------+---------------+
    | Protocol-ID | NLRI information source protocol |   Reference   |
    +-------------+----------------------------------+---------------+
    |     TBD     7       |          RSVP-TE                 | this document |
    |     TBD     8       |       Segment Routing            | this document |
    +-------------+----------------------------------+---------------+

4.3.  BGP-LS Instance-IDs Descriptors TLVs

   IANA maintains a registry called "Border Gateway Protocol - Link
   State (BGP-LS) Parameters" with a sub-registry called "BGP-LS Well-
   known Instance-IDs".

   IANA is requested to assign one new Instance-ID:

    +------------+----------------------------------+---------------+ "Node Anchor,
   Link Descriptor and Link Attribute TLVs".

   The following TLV codepoints are suggested (to be assigned by IANA):

   +----------+--------------------------------------+---------------+
   | Identifier TLV Code | Routing Universe             Description              | Reference: Value defined |
    +------------+----------------------------------+---------------+
   |    TBD  Point   |                                      |       in      |
   +----------+--------------------------------------+---------------+
   |   1158   |   LSP State TLV                      | this document | Default Optical Network Topology
   |    267   |   Tunnel ID TLV                      | this document |
   |    268   |   LSP ID TLV                         | this document |
   |    269   |   IPv4/6 Tunnel Head-end address TLV | this document |
   |    270   |   IPv4/6 Tunnel Tail-end address TLV | this document |
   |    271   |   SR-ENCAP Identifier TLV            | this document |
    +------------+----------------------------------+---------------+
   +----------+--------------------------------------+---------------+

4.4.  BGP-LS Attribute TLVs LSP-State TLV Protocol Origin

   This document requests IANA maintains to maintain a registry called new sub-registry under
   "Border Gateway Protocol - Link State (BGP-LS) Parameters" with a sub-registry Parameters".  The new
   registry is called "Node Anchor,
   Link Descriptor "Protocol Origin" and Link Attribute TLVs".

   IANA is requested contains the codepoints
   allocated to assign one new TLV code point:

   +-----------+---------------------+---------------+-----------------+ the "Protocol Origin" field defined in Section 2.3.  The
   registry contains the following codepoints (suggested values, to be
   assigned by IANA):

              +----------+--------------+
              |  TLV Code Protocol |  Description |   IS-IS TLV/
              | Value defined  Origin  |              |   Point
              +----------+--------------+
              |    1     |    Sub-TLV  RSVP-TE     | in:
              |
   +-----------+---------------------+---------------+-----------------+    2     |    TBD  PCE         |   LSP State TLV
              |      ---    3     | this document  SR-ENCAP    |
   +-----------+---------------------+---------------+-----------------+
              +----------+--------------+

5.  Security Considerations

   Procedures and protocol extensions defined in this document do not
   affect the BGP security model.  See [RFC6952] for details.

6.  Acknowledgements

   The authors would like to thank Dhruv Dhody and Dhody, Mohammed Abdul Aziz
   Khalid
   Khalid, Lou Berger, Acee Lindem, Siva Sivabalan and Arjun Sreekantiah
   for their review and valuable comments.

7.  References

7.1.  Normative References

   [I-D.ietf-idr-ls-distribution]
              Gredler, H., Medved, J., Previdi, S., Farrel, A., and S.
              Ray, "North-Bound Distribution of Link-State and TE
              Information using BGP", draft-ietf-idr-ls-distribution-10 draft-ietf-idr-ls-distribution-13
              (work in progress), January October 2015.

   [I-D.sreekantiah-idr-segment-routing-te]
              Sreekantiah, A., Filsfils, C., Previdi, S., Sivabalan, S.,
              Mattes, P., and J. Marcon, "Segment Routing Traffic
              Engineering Policy using BGP", draft-sreekantiah-idr-
              segment-routing-te-00 (work in progress), October 2015.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997. 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC2205]  Braden, B., R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
              Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
              Functional Specification", RFC 2205, DOI 10.17487/RFC2205,
              September 1997. 1997, <http://www.rfc-editor.org/info/rfc2205>.

   [RFC3209]  Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
              and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
              Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001. 2001,
              <http://www.rfc-editor.org/info/rfc3209>.

   [RFC3473]  Berger, L., Ed., "Generalized Multi-Protocol Label
              Switching (GMPLS) Signaling Resource ReserVation Protocol-Traffic Protocol-
              Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
              DOI 10.17487/RFC3473, January 2003. 2003,
              <http://www.rfc-editor.org/info/rfc3473>.

   [RFC4090]  Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast
              Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
              DOI 10.17487/RFC4090, May
              2005. 2005,
              <http://www.rfc-editor.org/info/rfc4090>.

   [RFC4760]  Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
              "Multiprotocol Extensions for BGP-4", RFC 4760,
              DOI 10.17487/RFC4760, January
              2007. 2007,
              <http://www.rfc-editor.org/info/rfc4760>.

   [RFC4872]  Lang, J., Ed., Rekhter, Y., Ed., and D. Papadimitriou,
              Ed., "RSVP-TE Extensions in Support of End-to-End
              Generalized Multi-
              Protocol Multi-Protocol Label Switching (GMPLS)
              Recovery", RFC 4872, DOI 10.17487/RFC4872, May
              2007. 2007,
              <http://www.rfc-editor.org/info/rfc4872>.

   [RFC4873]  Berger, L., Bryskin, I., Papadimitriou, D., and A. Farrel,
              "GMPLS Segment Recovery", RFC 4873, DOI 10.17487/RFC4873,
              May 2007. 2007, <http://www.rfc-editor.org/info/rfc4873>.

   [RFC4874]  Lee, CY., Farrel, A., and S. De Cnodder, "Exclude Routes -
              Extension to Resource ReserVation Protocol-Traffic
              Engineering (RSVP-TE)", RFC 4874, DOI 10.17487/RFC4874,
              April 2007. 2007, <http://www.rfc-editor.org/info/rfc4874>.

   [RFC5420]  Farrel, A., Ed., Papadimitriou, D., Vasseur, JP., and A.
              Ayyangarps, "Encoding of Attributes for MPLS LSP
              Establishment Using Resource Reservation Protocol Traffic
              Engineering (RSVP-TE)", RFC 5420, DOI 10.17487/RFC5420,
              February 2009. 2009, <http://www.rfc-editor.org/info/rfc5420>.

   [RFC5440]  Vasseur, JP. JP., Ed. and JL. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol (PCEP)", RFC 5440,
              DOI 10.17487/RFC5440, March
              2009. 2009,
              <http://www.rfc-editor.org/info/rfc5440>.

7.2.  Informative References

   [I-D.ietf-pce-stateful-pce]
              Crabbe, E., Minei, I., Medved, J., and R. Varga, "PCEP
              Extensions for Stateful PCE", draft-ietf-pce-stateful-
              pce-11
              pce-13 (work in progress), April December 2015.

   [RFC4655]  Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
              Element (PCE)-Based Architecture", RFC 4655,
              DOI 10.17487/RFC4655, August 2006. 2006,
              <http://www.rfc-editor.org/info/rfc4655>.

   [RFC6952]  Jethanandani, M., Patel, K., and L. Zheng, "Analysis of
              BGP, LDP, PCEP, and MSDP Issues According to the Keying
              and Authentication for Routing Protocols (KARP) Design
              Guide", RFC 6952, DOI 10.17487/RFC6952, May 2013. 2013,
              <http://www.rfc-editor.org/info/rfc6952>.

Authors' Addresses

   Jie Dong
   Huawei Technologies
   Huawei Campus, No. 156 Beiqing Rd.
   Beijing  100095
   China

   Email: jie.dong@huawei.com

   Mach(Guoyi) Chen
   Huawei Technologies
   Huawei Campus, No. 156 Beiqing Rd.
   Beijing  100095
   China

   Email: mach.chen@huawei.com

   Hannes Gredler
   Juniper Networks, Inc.
   1194 N. Mathilda Ave.
   Sunnyvale, CA  94089
   US
   Individual Contributor
   Austria

   Email: hannes@juniper.net hannes@gredler.at

   Stefano Previdi
   Cisco Systems, Inc.
   Via Del Serafico, 200
   Rome  00142
   Italy

   Email: sprevidi@cisco.com
   Jeff Tantsura
   Ericsson
   300 Holger Way
   San Jose, CA  95134
   US

   Email: jeff.tantsura@ericsson.com