OSPF Link-Local Signaling (LLS) Extensions for Local Interface ID Advertisement
RFC 8510

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 00
• 01
• 02
• 03
• 04
• 05
• 06
• 07
• 08
• 09

Internet Engineering Task Force (IETF)                    P. Psenak, Ed.
Request for Comments: 8510                                 K. Talaulikar
Category: Standards Track                            Cisco Systems, Inc.
ISSN: 2070-1721                                            W. Henderickx
                                                                   Nokia
                                                       P. Pillay-Esnault
                                                              Huawei USA
                                                            January 2019

             OSPF Link-Local Signaling (LLS) Extensions for
                    Local Interface ID Advertisement

Abstract

   Every OSPF interface is assigned an Interface ID that uniquely
   identifies the interface on the router.  In some cases, it is useful
   to know the assigned Interface ID on the remote side of the adjacency
   (Remote Interface ID).

   This document describes the extensions to OSPF link-local signaling
   (LLS) to advertise the Local Interface ID.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 7841.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   https://www.rfc-editor.org/info/rfc8510.

Psenak, et al.               Standards Track                    [Page 1]
RFC 8510          OSPF LLS Extensions for Interface ID      January 2019

Copyright Notice

   Copyright (c) 2019 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
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1. Introduction ....................................................3
      1.1. Interface ID Exchange Using Link Local TE Opaque LSA .......4
      1.2. Requirements Language ......................................4
   2. Interface ID Exchange Using OSPF LLS ............................4
      2.1. Local Interface ID TLV .....................................5
   3. Backward Compatibility with RFC 4203 ............................5
   4. IANA Considerations .............................................6
   5. Security Considerations .........................................6
   6. References ......................................................6
      6.1. Normative References .......................................6
      6.2. Informative References .....................................7
   Acknowledgments ....................................................8
   Authors' Addresses .................................................8

Psenak, et al.               Standards Track                    [Page 2]
RFC 8510          OSPF LLS Extensions for Interface ID      January 2019

1.  Introduction

   Every OSPF interface is assigned an Interface ID that uniquely
   identifies the interface on the router.  [RFC2328] uses this
   Interface ID in the Router Link State Advertisement (Router-LSA) Link
   Data for unnumbered links and uses the value of the MIB-II ifIndex
   [RFC2863].  [RFC4203] refers to these Interface IDs as the Link
   Local/Remote Identifiers and defines a way to advertise and use them
   for GMPLS purposes.  [RFC8379] defines a way to advertise Local/
   Remote Interface IDs in the OSPFv2 Extended Link Opaque LSA.

   There is a known OSPFv2 protocol problem in verifying the
   bidirectional connectivity with parallel unnumbered links.  If there
   are two parallel unnumbered links between a pair of routers and each
   link is only advertised from a single direction, such two
   unidirectional parallel links could be considered as a valid single
   bidirectional link during the OSPF route computation on some other
   router.  If each link is advertised with both its Local and Remote
   Interface IDs, the advertisement of each link from both sides of
   adjacency can be verified by cross-checking the Local and Remote
   Interface IDs of both advertisements.

   From the perspective of the advertising router, the Local Interface
   ID is a known value.  However, the Remote Interface ID needs to be