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Versions: (draft-dong-idr-te-lsp-distribution) 00 01 02 03 04 05 06 07

Network Working Group                                    S. Previdi, Ed.
Internet-Draft                                       Cisco Systems, Inc.
Intended status: Standards Track                            J. Dong, Ed.
Expires: January 2, 2018                                         M. Chen
                                                     Huawei Technologies
                                                              H. Gredler
                                                            RtBrick Inc.
                                                             J. Tantsura
                                                              Individual
                                                            July 1, 2017


Distribution of Traffic Engineering (TE) Policies and State using BGP-LS
                 draft-ietf-idr-te-lsp-distribution-07

Abstract

   This document describes a mechanism to collect the Traffic
   Engineering and Policy information that is locally available in a
   router and advertise it into BGP-LS updates.  Such information can be
   used by external components for path computation, re-optimization,
   service placement, network visualization, etc.

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
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

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

   This Internet-Draft will expire on January 2, 2018.






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Copyright Notice

   Copyright (c) 2017 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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Carrying TE Policy Information in BGP . . . . . . . . . . . .   5
     2.1.  TE Policy Information . . . . . . . . . . . . . . . . . .   5
     2.2.  TE Policy NLRI  . . . . . . . . . . . . . . . . . . . . .   5
       2.2.1.  TE Policy Descriptors . . . . . . . . . . . . . . . .   7
     2.3.  TE Policy State . . . . . . . . . . . . . . . . . . . . .  12
       2.3.1.  RSVP Objects  . . . . . . . . . . . . . . . . . . . .  14
       2.3.2.  PCE Objects . . . . . . . . . . . . . . . . . . . . .  15
       2.3.3.  SR TE Policy Sub-TLVs . . . . . . . . . . . . . . . .  16
   3.  Operational Considerations  . . . . . . . . . . . . . . . . .  22
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  22
     4.1.  BGP-LS NLRI-Types . . . . . . . . . . . . . . . . . . . .  22
     4.2.  BGP-LS Protocol-IDs . . . . . . . . . . . . . . . . . . .  23
     4.3.  BGP-LS Descriptors TLVs . . . . . . . . . . . . . . . . .  23
     4.4.  BGP-LS LSP-State TLV Path Origin  . . . . . . . . . . . .  23
     4.5.  BGP-LS LSP-State TLV Dataplane  . . . . . . . . . . . . .  24
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  24
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  24
   7.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  24
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  25
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  25
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  26
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  27

1.  Introduction

   In many network environments, traffic engineering policies are
   instantiated into various forms:

   o  MPLS Traffic Engineering Label Switched Paths (TE-LSPs).




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   o  IP based tunnels (IP in IP, GRE, etc).

   o  Segment Routing Traffic Engineering Policies (SR TE Policy) as
      defined in [I-D.previdi-idr-segment-routing-te-policy]

   o  Local cross-connect configuration

   All this information can be grouped into the same term: TE Policies.
   In the rest of this document we refer to TE Policies as the set of
   information related to the various instantiation of polices: MPLS TE
   LSPs, IP tunnels (IPv4 or IPv6), SR TE Policies, etc.

   TE Polices are generally instantiated by the head-end and are based
   on either local configuration or controller based programming of the
   node using various protocols and APIs, e.g., PCEP or BGP.

   In many network environments, the configuration and state of each TE
   Policy that is available in the network is required by a controller
   which allows the network operator to optimize several functions and
   operations through the use of a controller aware of both topology and
   state information.

   One example of a controller is the stateful Path Computation Element
   (PCE) [I-D.ietf-pce-stateful-pce], which could provide benefits in
   path 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-LSPs may not implement the
   PCEP protocol.  In this case a general mechanism to collect the TE-
   LSP states from the ingress LERs is needed.  This document proposes
   an TE Policy state collection mechanism complementary to the
   mechanism defined in [I-D.ietf-pce-stateful-pce].
















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                                   -----------
                                  |   -----   |
              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], 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 TE Policy information to
   the PCE nodes.  An external component may also need to collect the TE
   Policy information from all the PCEs in the network to obtain a
   global view of the LSP state in the network.

   In multi-area or multi-AS scenarios, each area or AS can have a child
   PCE to collect the TE Policies in its own domain, in addition, a
   parent PCE needs to collect TE Policy 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 Policy state information is
   quite important for making appropriate service placement decisions
   with the purpose to both meet the application's requirements and
   utilize network resources efficiently.

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

   BGP has been extended to distribute link-state and traffic
   engineering information to external components [RFC7752].  Using the
   same protocol to collect Traffic Engineering and Policy information



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   is desirable for these external components since this avoids
   introducing multiple protocols for network information collection.
   This document describes a mechanism to distribute traffic engineering
   and policy information (MPLS, IPv4 and IPv6) to external components
   using BGP-LS.

2.  Carrying TE Policy Information in BGP

2.1.  TE Policy Information

   TE Policy information is advertised in BGP UPDATE messages using the
   MP_REACH_NLRI and MP_UNREACH_NLRI attributes [RFC4760].  The "Link-
   State NLRI" defined in [RFC7752] is extended to carry the TE Policy
   information.  BGP speakers that wish to exchange TE Policy
   information MUST use the BGP Multiprotocol Extensions Capability Code
   (1) to advertise the corresponding (AFI, SAFI) pair, as specified in
   [RFC4760].  A new TLV carried in the Link_State Attribute defined in
   [RFC7752] is also defined in order to carry the attributes of a TE
   Policy (Section 2.3).

   The format of "Link-State NLRI" is defined in [RFC7752].  A new "NLRI
   Type" is defined for TE Policy Information as following:

   o  NLRI Type: TE Policy NLRI (suggested codepoint value 5, to be
      assigned by IANA).

   [RFC7752] defines the 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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |            NLRI Type          |     Total NLRI Length         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
     //                  Link-State NLRI (variable)                 //
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   This document defines a new NLRI-Type and its format: the TE Policy
   NLRI defined in the following section.

2.2.  TE Policy NLRI

   The TE Policy NLRI (NLRI Type 5.  Suggested value, to be assigned by
   IANA) is shown in the following figure:






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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
     +-+-+-+-+-+-+-+-+
     |  Protocol-ID  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                        Identifier                             |
     |                        (64 bits)                              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //                Headend (Node Descriptors)                   //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //                TE Policy Descriptors (variable)             //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Protocol-ID field specifies the component that owns the TE Policy
      state in the advertising node.  The following Protocol-IDs are
      defined (suggested values, to be assigned by IANA) and apply to
      the TE Policy NLRI:

               +-------------+----------------------------------+
               | Protocol-ID | NLRI information source protocol |
               +-------------+----------------------------------+
               |      8      |   RSVP-TE                        |
               |      9      |   Segment Routing                |
               +-------------+----------------------------------+

   o  "Identifier" is an 8 octet value as defined in [RFC7752].

   o  "Headend" consists of a Node Descriptor defined in [RFC7752].

   o  "TE Policy Descriptors" consists of:

   +-----------+----------------------------------+
   | Codepoint |       Descriptor TLV             |
   +-----------+----------------------------------+
   |  267      | Tunnel ID                        |
   |  268      | LSP ID                           |
   |  269      | IPv4/6 Tunnel Head-end address   |
   |  270      | IPv4/6 Tunnel Tail-end address   |
   |  271      | SR TE Policy                     |
   |  272      | Local Cross Connect              |
   +-----------+----------------------------------+








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2.2.1.  TE Policy Descriptors

   This sections defines the TE Policy Descriptors TLVs.

2.2.1.1.  Tunnel Identifier (Tunnel ID)

   The Tunnel Identifier TLV contains the Tunnel 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               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |         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].






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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).





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

2.2.1.5.  SR TE Policy TLV

   The SR TE Policy TLV identifies a SR TE Policy as defined in
   [I-D.previdi-idr-segment-routing-te-policy] 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               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                     Distinguisher (4 octets)                  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                     Policy Color (4 octets)                   |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                     Endpoint (4 or 16 octets)                 |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


     where:

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

   o  Length: 12 octets.

   o  Distinguisher, Policy Color and Endpoint are defined in
      [I-D.previdi-idr-segment-routing-te-policy].

2.2.1.6.  MPLS Cross Connect

   The MPLS Cross Connect TLV identifies a local MPLS state in the form
   of incoming label and interface followed by an outgoing label and
   interface.  Outgoing interface may appear multiple times (for
   multicast states).

   The Local Cross Connect TLV has the following format:












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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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |             Type              |          Length               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                     Incoming label (4 octets)                 |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                     Outgoing label (4 octets)                 |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //                          Sub-TLVs (variable)                //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

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

   o  Length: variable.

   o  Incoming and Outgoing labels: 4 octets each.

   o  Sub-TLVs: following Sub-TLVs are defined:

      *  Interface Sub-TLV

      *  Forwarding Equivalent Class (FEC)

   The MPLS Cross Connect TLV:

      MUST have an incoming label.

      MUST have an outgoing label.

      MAY contain an Interface Sub-TLV having the I-flag set.

      MUST contain at least one Interface Sub-TLV having the I-flag
      unset.

      MAY contain multiple Interface Sub-TLV having the I-flag unset.
      This is the case of a multicast MPLS cross connect.

      MAY contain a FEC Sub-TLV.

2.2.1.6.1.  MPLS Cross Connect Sub-TLVs








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2.2.1.6.1.1.  Interface Sub-TLV

   The Interface sub-TLV is optional and contains the identifier of the
   interface (incoming or outgoing) in the form of an IPv4 address or an
   IPv6 address.

   The Interface sub-TLV 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               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     +-+-+-+-+-+-+-+-+
     |     Flags     |
     +-+-+-+-+-+-+-+-+

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          Local Interface Identifier (4 octets)                |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //         Interface Address (4 or 16 octets)                  //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Type: To be assigned by IANA (suggested value: 1)

   o  Length: 9 or 21.

   o  Flags: 1 octet of flags defined as follows:

                              0 1 2 3 4 5 6 7
                             +-+-+-+-+-+-+-+-+
                             |I|             |
                             +-+-+-+-+-+-+-+-+

                             where:

      *  I-Flag is the Interface flag.  When set, the Interface Sub-TLV
         describes an incoming interface.  If the I-flag is not set,
         then the Interface Sub-TLV describes an outgoing interface.

   o  Local Interface Identifier: a 4 octet identifier.

   o  Interface address: a 4 octet IPv4 address or a 16 octet IPv6
      address.




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2.2.1.6.1.2.  Forwarding Equivalent Class (FEC) Sub-TLV

   The FEC sub-TLV is optional and contains the FEC associated to the
   incoming label.

   The FEC sub-TLV 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               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Flags       |  Masklength   |   Prefix (variable)          //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //                     Prefix (variable)                       //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

   o  Type: To be assigned by IANA (suggested value: 2)

   o  Length: variable.

   o  Flags: 1 octet of flags defined as follows:

                              0 1 2 3 4 5 6 7
                             +-+-+-+-+-+-+-+-+
                             |4|             |
                             +-+-+-+-+-+-+-+-+

                             where:

      *  4-Flag is the IPv4 flag.  When set, the FEC Sub-TLV describes
         an IPv4 FEC.  If the 4-flag is not set, then the FEC Sub-TLV
         describes an IPv6 FEC.

   o  Mask Length: 1 octet of prefix length.

   o  Prefix: an IPv4 or IPv6 prefix whose mask length is given by the "
      Mask Length" field.

2.3.  TE Policy State

   A new TLV called "TE Policy State TLV" (codepoint to be assigned by
   IANA), is used to describe the characteristics of the TE Policy,
   which is carried in the optional non-transitive BGP Attribute
   "LINK_STATE Attribute" defined in [RFC7752].  These TE Policy
   characteristics include the characteristics and attributes of the



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   policy, it's dataplane, explicit path, 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            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Path-origin  |   Dataplane   |            RESERVED           |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     //            TE Policy State Sub-TLVs (variable)              //
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     where:

                            TE Policy State TLV

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

   o  Length: the total length of the TE Policy State TLV not including
      Type and Length fields.

   o  Path-origin: identifies the component (or protocol) from which the
      contained object originated.  This allows for objects defined in
      different components to be collected while avoiding the possible
      code collisions among these components.  Following path-origin
      codepoints are defined in this document (suggested values, to be
      assigned by IANA).

               +----------+------------------+
               |  Code    |     Path         |
               |  Point   |     Origin       |
               +----------+------------------+
               |    1     | RSVP-TE          |
               |    2     | PCE              |
               |    3     | BGP SR TE Policy |
               |    4     | NETCONF          |
               |    5     | Static           |
               +----------+------------------+

   o  Dataplane: describes to which dataplane the policy is applied to.
      The following dataplane values are defined:







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               +----------+------------------+
               |  Code    |    Dataplane     |
               |  Point   |                  |
               +----------+------------------+
               |    1     | MPLS-IPv4        |
               |    2     | MPLS-IPv6        |
               |    3     | IPv6             |
               +----------+------------------+

   o  RESERVED: 16-bit field field.  SHOULD be set to 0 on transmission
      and MUST be ignored on receipt.

   TE Policy State sub-TLVs: objects as defined in [RFC3209],[RFC3473],
   [RFC5440] and [I-D.previdi-idr-segment-routing-te-policy].  Rather
   than replicating all these objects in this document, the semantics
   and encodings of the objects are reused.  These objects are carried
   in the "TE Policy State Information" with the following format.

2.3.1.  RSVP Objects

   RSVP-TE objects are encoded in the "Value" field of the LSP State TLV
   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 are re-used.  These MPLS TE LSP objects are carried in the
   LSP State TLV.

   When carrying RSVP-TE objects, the "Path-Origin" field is set to
   "RSVP-TE".

   The following RSVP-TE Objects are defined:

   o  SENDER_TSPEC and FLOW_SPEC [RFC2205]

   o  SESSION_ATTRIBUTE [RFC3209]

   o  EXPLICIT_ROUTE Object (ERO) [RFC3209]

   o  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]




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   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  LABEL_REQUEST Object [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 "Path-Origin" field is set to "PCE".

   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.








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2.3.3.  SR TE Policy Sub-TLVs

   Segment Routing Traffic Engineering Policy (SR TE Policy) as
   described in [I-D.previdi-idr-segment-routing-te-policy]makes use of
   the Tunnel Encapsulation Attribute defined in
   [I-D.ietf-idr-tunnel-encaps] and defines following sub-TLVs:

   o  Preference

   o  Binding SID

   o  Weight

   o  Segment List

   o  Segment

   The equivalent sub-TLVs are defined hereafter and carried in the TE
   Policy State TLV.  When carrying SR TE Policy objects, the "Path-
   Origin" field is set to "BGP SR TE Policy".

2.3.3.1.  Preference Object

   The Preference sub-TLV 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      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Preference (4 octets)                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   All fields, including type and length, are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.2.  SR TE Binding SID Sub-TLV

   The Binding SID sub-TLV 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      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              Binding SID (variable, optional)                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+




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   All fields, including type and length, are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

   [I-D.previdi-idr-segment-routing-te-policy] specifies the Binding SID
   sub-TLV which carries an indication of which value to allocate as
   Binding SID to the SR TE Policy.  In the context of the BGP-LS
   extensions defined in this document, the Binding SID sub-TLV to the
   reciever of the , the Binding SID TLThe Binding SID sub-TLV contains
   the Binding SID the originator of the BGP-LS update has allocated to
   the corresponding SR TE Policy.

   In the context of BGP-LS, the Binding SID sub-TLV defined in this
   document, contains the effective value of the Binding SID that the
   router allocated to the SR TE Policy.  The router is the SR TE Policy
   receiver (as described in
   [I-D.previdi-idr-segment-routing-te-policy]) and it is also the
   originator of the corresponding BGP-LS update with the extensions
   defined in this document.

2.3.3.3.  Weight Sub-TLV

   The Weight sub-TLV 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      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              Weight                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   All fields, including type and length, are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.4.  Segment List Sub-TLV

   The Segment List object contains sub-TLVs (which in fact are sub-sub-
   TLVs) 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            |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                           sub-TLVs                          //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+





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   o  All fields, including type and length, are defined in
      [I-D.previdi-idr-segment-routing-te-policy].

   o  Length is the total length (not including the Type and Length
      fields) of the sub-TLVs encoded within the Segment List sub-TLV.

   o  sub-objects:

      *  An optional single Weight sub-TLV.

      *  One or more Segment sub-TLVs.

   The Segment List sub-TLV is mandatory.

   Multiple occurrences of the Segment List sub-TLV MAY appear in the SR
   TE Policy.

2.3.3.5.  Segment Sub-TLV

   The Segment sub-TLV describes a single segment in a segment list
   (i.e.: a single element of the explicit path).  Multiple Segment sub-
   TLVs constitute an explicit path of the SR TE Policy.

   [I-D.previdi-idr-segment-routing-te-policy] defines 8 different types
   of Segment Sub-TLVs:

   Type 1: SID only, in the form of MPLS Label
   Type 2: SID only, in the form of IPv6 address
   Type 3: IPv4 Node Address with optional SID
   Type 4: IPv6 Node Address with optional SID
   Type 5: IPv4 Address + index with optional SID
   Type 6: IPv4 Local and Remote addresses with optional SID
   Type 7: IPv6 Address + index with optional SID
   Type 8: IPv6 Local and Remote addresses with optional SID

2.3.3.5.1.  Type 1: SID only, in the form of MPLS Label

   The Type-1 Segment Sub-TLV encodes a single SID in the form of an
   MPLS label.  The format is 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Length      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Label                        | TC  |S|       TTL     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+




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   Type, Length and values are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.5.2.  Type 2: SID only, in the form of IPv6 address

   The Type-2 Segment Sub-TLV encodes a single SID in the form of an
   IPv6 address.  The format is 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Length      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                       IPv6 SID (16 octets)                  //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type, Length and values are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.5.3.  Type 3: IPv4 Node Address with optional SID

   The Type-3 Segment Sub-TLV encodes an IPv4 node address and an
   optional SID in the form of either an MPLS label or an IPv6 address.
   The format is 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Length      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 IPv4 Node Address (4 octets)                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                SID (optional, 4 or 16 octets)               //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type, Length and values are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.5.4.  Type 4: IPv6 Node Address with optional SID

   The Type-4 Segment Sub-TLV encodes an IPv6 node address and an
   optional SID in the form of either an MPLS label or an IPv6 address.
   The format is as follows:








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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Length      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                IPv6 Node Address (16 octets)                //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                SID (optional, 4 or 16 octets)               //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type, Length and values are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.5.5.  Type 5: IPv4 Address + index with optional SID

   The Type-5 Segment Sub-TLV encodes an IPv4 node address, an interface
   index and an optional SID in the form of either an MPLS label or an
   IPv6 address.  The format is 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Length      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 IfIndex (4 octets)                            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 IPv4 Node Address (4 octets)                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                SID (optional, 4 or 16 octets)               //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type, Length and values are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.5.6.  Type 6: IPv4 Local and Remote addresses with optional SID

   The Type-6 Segment Sub-TLV encodes an IPv4 node address, an adjacency
   local address, an adjacency remote address and an optional SID in the
   form of either an MPLS label or an IPv6 address.  The format is as
   follows:











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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Length      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Local IPv4 Address (4 octets)                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                Remote IPv4 Address  (4 octets)                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                     SID (4 or 16 octets)                    //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type, Length and values are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.5.7.  Type 7: IPv6 Address + index with optional SID

   The Type-7 Segment Sub-TLV encodes an IPv6 node address, an interface
   index and an optional SID in the form of either an MPLS label or an
   IPv6 address.  The format is 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Length      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 IfIndex (4 octets)                            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                IPv6 Node Address (16 octets)                //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                SID (optional, 4 or 16 octets)               //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type, Length and values are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

2.3.3.5.8.  Type 8: IPv6 Local and Remote addresses with optional SID

   The Type-8 Segment Sub-TLV encodes an IPv6 node address, an adjacency
   local address, an adjacency remote address and an optional SID in the
   form of either an MPLS label or an IPv6 address.  The format is as
   follows:









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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Length      |     Flags     |   RESERVED    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //               Local IPv6 Address (16 octets)                //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //               Remote IPv6 Address  (16 octets)              //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   //                     SID (4 or 16 octets)                    //
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type, Length and values are defined in
   [I-D.previdi-idr-segment-routing-te-policy].

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 [RFC7752] apply to this
   document.

   In general, it is assumed that the TE Policy head-end nodes are
   responsible for the distribution of TE Policy state information,
   while other nodes, e.g. the nodes in the path of a policy, MAY report
   the TE Policy information (if available) when needed.  For example,
   the border routers in the inter-domain case will also distribute LSP
   state information since the ingress node may not have the complete
   information for the end-to-end path.

4.  IANA Considerations

   This document requires new 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".

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

    +------+----------------------------+---------------+
    | Type | NLRI Type                  |   Reference   |
    +------+----------------------------+---------------+
    |  5   | TE Policy NLRI type        | this document |
    +------+----------------------------+---------------+




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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".

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

    +-------------+----------------------------------+---------------+
    | Protocol-ID | NLRI information source protocol |   Reference   |
    +-------------+----------------------------------+---------------+
    |     8       |          RSVP-TE                 | this document |
    |     9       |       Segment Routing            | this document |
    +-------------+----------------------------------+---------------+

4.3.  BGP-LS Descriptors TLVs

   IANA maintains a registry called "Border Gateway Protocol - Link
   State (BGP-LS) Parameters" with a sub-registry called "Node Anchor,
   Link Descriptor and Link Attribute TLVs".

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

   +----------+--------------------------------------+---------------+
   | TLV Code |             Description              | Value defined |
   |  Point   |                                      |       in      |
   +----------+--------------------------------------+---------------+
   |   1158   |   TE Policy State TLV                | this document |
   |    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 TE Policy Identifier TLV        | this document |
   +----------+--------------------------------------+---------------+

4.4.  BGP-LS LSP-State TLV Path Origin

   This document requests IANA to maintain a new sub-registry under
   "Border Gateway Protocol - Link State (BGP-LS) Parameters".  The new
   registry is called "Path Origin" and contains the codepoints
   allocated to the "Path Origin" field defined in Section 2.3.  The
   registry contains the following codepoints (suggested values, to be
   assigned by IANA):







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               +----------+------------------+
               |  Code    |     Path         |
               |  Point   |     Origin       |
               +----------+------------------+
               |    1     | RSVP-TE          |
               |    2     | PCE              |
               |    3     | BGP SR TE Policy |
               |    4     | NETCONF          |
               |    5     | Static           |
               +----------+------------------+

4.5.  BGP-LS LSP-State TLV Dataplane

   This document requests IANA to maintain a new sub-registry under
   "Border Gateway Protocol - Link State (BGP-LS) Parameters".  The new
   registry is called "Dataplane" and contains the codepoints allocated
   to the "dataplane" field defined in Section 2.3.  The registry
   contains the following codepoints (suggested values, to be assigned
   by IANA):

               +----------+------------------+
               |  Code    |   Dataplane      |
               |  Point   |                  |
               +----------+------------------+
               |    1     | MPLS-IPv4        |
               |    2     | MPLS-IPv6        |
               |    3     | IPv6             |
               +----------+------------------+

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, Mohammed Abdul Aziz
   Khalid, Lou Berger, Acee Lindem, Siva Sivabalan, Arjun Sreekantiah,
   and Dhanendra Jain for their review and valuable comments.

7.  Contributors

   The following people have substantially contributed to the editing of
   this document:

   Ketan Talaulikar
   Cisco Systems
   Email: ketant@cisco.com



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   Clarence Filsfils
   Cisco Systems
   Email: cfilsfil@cisco.com

8.  References

8.1.  Normative References

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

   [RFC2205]  Braden, 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, <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,
              <http://www.rfc-editor.org/info/rfc3209>.

   [RFC3473]  Berger, L., Ed., "Generalized Multi-Protocol Label
              Switching (GMPLS) Signaling Resource ReserVation Protocol-
              Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
              DOI 10.17487/RFC3473, January 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,
              <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,
              <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 Label Switching (GMPLS)
              Recovery", RFC 4872, DOI 10.17487/RFC4872, May 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, <http://www.rfc-editor.org/info/rfc4873>.



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   [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, <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, <http://www.rfc-editor.org/info/rfc5420>.

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

   [RFC7752]  Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
              S. Ray, "North-Bound Distribution of Link-State and
              Traffic Engineering (TE) Information Using BGP", RFC 7752,
              DOI 10.17487/RFC7752, March 2016,
              <http://www.rfc-editor.org/info/rfc7752>.

8.2.  Informative References

   [I-D.ietf-idr-tunnel-encaps]
              Rosen, E., Patel, K., and G. Velde, "The BGP Tunnel
              Encapsulation Attribute", draft-ietf-idr-tunnel-encaps-06
              (work in progress), June 2017.

   [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-21 (work in progress), June 2017.

   [I-D.previdi-idr-segment-routing-te-policy]
              Previdi, S., Filsfils, C., Mattes, P., Rosen, E., and S.
              Lin, "Advertising Segment Routing Policies in BGP", draft-
              previdi-idr-segment-routing-te-policy-07 (work in
              progress), June 2017.

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







Previdi, et al.          Expires January 2, 2018               [Page 26]


Internet-Draft  MPLS TE LSP State Distribution using BGP       July 2017


   [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,
              <http://www.rfc-editor.org/info/rfc6952>.

Authors' Addresses

   Stefano Previdi (editor)
   Cisco Systems, Inc.

   Email: stefano@previdi.net


   Jie Dong (editor)
   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
   RtBrick Inc.

   Email: hannes@rtbrick.com


   Jeff Tantsura
   Individual

   Email: jefftant@gmail.com









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