OSPF Extensions in Support of Inter-Autonomous System (AS) MPLS and GMPLS Traffic Engineering
RFC 5392

Network Working Group                                           M. Chen
Request for Comments: 5392                                     R. Zhang
Category: Standards Track                 Huawei Technologies Co., Ltd.
                                                                X. Duan
                                                           China Mobile
                                                           January 2009

      OSPF Extensions in Support of Inter-Autonomous System (AS)
                  MPLS and GMPLS Traffic Engineering

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

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Abstract

   This document describes extensions to the OSPF version 2 and 3
   protocols to support Multiprotocol Label Switching (MPLS) and
   Generalized MPLS (GMPLS) Traffic Engineering (TE) for multiple
   Autonomous Systems (ASes).  OSPF-TE v2 and v3 extensions are defined
   for the flooding of TE information about inter-AS links that can be
   used to perform inter-AS TE path computation.

   No support for flooding information from within one AS to another AS
   is proposed or defined in this document.

Chen, et al.                Standards Track                     [Page 1]
RFC 5392            OSPF Extensions for Inter-AS TE         January 2009

Table of Contents

   1. Introduction ....................................................2
      1.1. Conventions Used in This Document ..........................3
   2. Problem Statement ...............................................3
      2.1. A Note on Non-Objectives ...................................4
      2.2. Per-Domain Path Determination ..............................4
      2.3. Backward Recursive Path Computation ........................6
   3. Extensions to OSPF ..............................................7
      3.1. LSA Definitions ............................................8
           3.1.1. Inter-AS-TE-v2 LSA ..................................8
           3.1.2. Inter-AS-TE-v3 LSA ..................................8
      3.2. LSA Payload ................................................9
           3.2.1. Link TLV ............................................9
      3.3. Sub-TLV Details ...........................................10
           3.3.1. Remote AS Number Sub-TLV ...........................10
           3.3.2. IPv4 Remote ASBR ID Sub-TLV ........................11
           3.3.3. IPv6 Remote ASBR ID Sub-TLV ........................11
   4. Procedure for Inter-AS TE Links ................................12
      4.1. Origin of Proxied TE Information ..........................13
   5. Security Considerations ........................................14
   6. IANA Considerations ............................................14
      6.1. Inter-AS TE OSPF LSA ......................................14
           6.1.1. Inter-AS-TE-v2 LSA .................................14
           6.1.2. Inter-AS-TE-v3 LSA .................................14
      6.2. OSPF LSA Sub-TLVs Type ....................................15
   7. Acknowledgments ................................................15
   8. References .....................................................15
      8.1. Normative References ......................................15
      8.2. Informative References ....................................16

1.  Introduction

   [OSPF-TE] defines extensions to the OSPF protocol [OSPF] to support
   intra-area Traffic Engineering (TE).  The extensions provide a way of
   encoding the TE information for TE-enabled links within the network
   (TE links) and flooding this information within an area.  Type 10
   Opaque Link State Advertisements (LSAs) [RFC5250] are used to carry
   such TE information.  Two top-level Type Length Values (TLVs) are
   defined in [OSPF-TE]: Router Address TLV and Link TLV.  The Link TLV
   has several nested sub-TLVs that describe the TE attributes for a TE
   link.

Chen, et al.                Standards Track                     [Page 2]