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 |
+--------+ | | | | | | | | +--------+
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