Internet Engineering Task Force (IETF) P. Muley
Request for Comments: 6718 M. Aissaoui
Category: Informational M. Bocci
ISSN: 2070-1721 Alcatel-Lucent
August 2012
Pseudowire Redundancy
Abstract
This document describes a framework comprised of a number of
scenarios and associated requirements for pseudowire (PW) redundancy.
A set of redundant PWs is configured between provider edge (PE) nodes
in single-segment PW applications or between terminating PE (T-PE)
nodes in multi-segment PW applications. In order for the PE/T-PE
nodes to indicate the preferred PW to use for forwarding PW packets
to one another, a new PW status is required to indicate the
preferential forwarding status of active or standby for each PW in
the redundant set.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
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). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6718.
Muley, et al. Informational [Page 1]RFC 6718 PW Redundancy August 2012Copyright Notice
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Table of Contents
1. Introduction ....................................................3
2. Terminology .....................................................4
2.1. Requirements Language ......................................6
3. Reference Models ................................................6
3.1. PE Architecture ............................................6
3.2. PW Redundancy Network Reference Scenarios ..................7
3.2.1. PW Redundancy for AC and PE Protection: One
Dual-Homed CE with Redundant SS-PWs .................7
3.2.2. PW Redundancy for AC and PE Protection: Two
Dual-Homed CEs with Redundant SS-PWs ................8
3.2.3. PW Redundancy for S-PE Protection:
Single-Homed CEs with Redundant MS-PWs .............10
3.2.4. PW Redundancy for PE-rs Protection in
H-VPLS Using SS-PWs ................................11
3.2.5. PW Redundancy for PE Protection in a VPLS
Ring Using SS-PWs ..................................13
3.2.6. PW Redundancy for VPLS n-PE Protection
Using SS-PWs .......................................14
4. Generic PW Redundancy Requirements .............................15
4.1. Protection Switching Requirements .........................15
4.2. Operational Requirements ..................................15
5. Security Considerations ........................................16
6. Contributors ...................................................16
7. Acknowledgements ...............................................17
8. References .....................................................17
8.1. Normative References ......................................17
8.2. Informative Reference .....................................18
Muley, et al. Informational [Page 2]RFC 6718 PW Redundancy August 20121. Introduction
The objective of pseudowire (PW) redundancy is to maintain
connectivity across the packet switched network (PSN) used by the
emulated service if a component in the path of the emulated service
datatracker.ietf.org