OSPF-Based Layer 1 VPN Auto-Discovery
RFC 5252

Network Working Group                                         I. Bryskin
Request for Comments: 5252                       ADVA Optical Networking
Category: Standards Track                                      L. Berger
                                                    LabN Consulting, LLC
                                                               July 2008

                 OSPF-Based Layer 1 VPN Auto-Discovery

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.

Abstract

   This document defines an Open Shortest Path First (OSPF) based Layer
   1 Virtual Private Network (L1VPN) auto-discovery mechanism.  This
   mechanism enables provider edge (PE) devices using OSPF to
   dynamically learn about the existence of each other, and attributes
   of configured customer edge (CE) links and their associations with
   L1VPNs.  This document builds on the L1VPN framework and requirements
   and provides a L1VPN basic mode auto-discovery mechanism.

Table of Contents

   1. Introduction ....................................................2
      1.1. Overview ...................................................2
      1.2. Terminology ................................................3
      1.3. Conventions Used in This Document ..........................4
   2. L1VPN LSA and Its TLVs ..........................................4
      2.1. L1VPN LSA ..................................................4
      2.2. L1VPN INFO TLV .............................................6
   3. L1VPN LSA Advertising and Processing ............................7
      3.1. Discussion and Example .....................................7
   4. Backward Compatibility ..........................................8
   5. Security Considerations .........................................9
   6. IANA Considerations .............................................9
   7. Acknowledgments .................................................9
   8. References ......................................................9
      8.1. Normative References .......................................9
      8.2. Informative References ....................................10

Bryskin & Berger            Standards Track                     [Page 1]
RFC 5252            OSPF-Based L1VPN Auto-Discovery            July 2008

1.  Introduction

1.1.  Overview

   The framework for Layer 1 VPNs is described in [RFC4847].  Basic mode
   operation is further defined in [RFC5251].  The L1VPN Basic Mode
   (L1VPN-BM) document [RFC5251] identifies the information that is
   necessary to map customer information (ports identifiers) to provider
   information (identifiers).  It also states that this mapping
   information may be provided via provisioning or via an auto-discovery
   mechanism.  This document provides such an auto-discovery mechanism
   using Open Shortest Path First (OSPF) version 2.  Use of OSPF version
   3 and support for IPv6 are out of scope of this document and will be
   defined separately.

   Figure 1 shows the L1VPN basic service being supported using OSPF-
   based L1VPN auto-discovery.  This figure shows two PE routers
   interconnected over a GMPLS backbone.  Each PE is attached to three
   CE devices belonging to three different L1VPN connections.  In this
   network, OSPF is used to provide the VPN membership, port mapping,
   and related information required to support basic mode operation.

                  PE                        PE
               +---------+             +--------------+
   +--------+  | +------+|             | +----------+ | +--------+
   |  VPN-A |  | |VPN-A ||             | |  VPN-A   | | |  VPN-A |
   |   CE1  |--| |PIT   ||  OSPF LSAs  | |  PIT     | |-|   CE2  |
   +--------+  | |      ||<----------->| |          | | +--------+
               | +------+| Distribution| +----------+ |
               |         |             |              |
   +--------+  | +------+|             | +----------+ | +--------+
   | VPN-B  |  | |VPN-B ||   -------   | |   VPN-B  | | |  VPN-B |
   |  CE1   |--| |PIT   ||--( GMPLS )--| |   PIT    | |-|   CE2  |
   +--------+  | |      ||  (Backbone) | |          | | +--------+
               | +------+|   --------  | +----------+ |
               |         |             |              |
   +--------+  | +-----+ |             | +----------+ | +--------+
   | VPN-C  |  | |VPN-C| |             | |   VPN-C  | | |  VPN-C |
   |  CE1   |--| |PIT  | |             | |   PIT    | |-|   CE2  |
   +--------+  | |     | |             | |          | | +--------+