Generalized Multi-Protocol Label Switching (GMPLS) Architecture
RFC 3945

Network Working Group                                     E. Mannie, Ed.
Request for Comments: 3945                                  October 2004
Category: Standards Track

    Generalized Multi-Protocol Label Switching (GMPLS) Architecture

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.

Copyright Notice

   Copyright (C) The Internet Society (2004).

Abstract

   Future data and transmission networks will consist of elements such
   as routers, switches, Dense Wavelength Division Multiplexing (DWDM)
   systems, Add-Drop Multiplexors (ADMs), photonic cross-connects
   (PXCs), optical cross-connects (OXCs), etc. that will use Generalized
   Multi-Protocol Label Switching (GMPLS) to dynamically provision
   resources and to provide network survivability using protection and
   restoration techniques.

   This document describes the architecture of GMPLS.  GMPLS extends
   MPLS to encompass time-division (e.g., SONET/SDH, PDH, G.709),
   wavelength (lambdas), and spatial switching (e.g., incoming port or
   fiber to outgoing port or fiber).  The focus of GMPLS is on the
   control plane of these various layers since each of them can use
   physically diverse data or forwarding planes.  The intention is to
   cover both the signaling and the routing part of that control plane.

Mannie                      Standards Track                     [Page 1]
RFC 3945                   GMPLS Architecture               October 2004

Table of Contents

   1.  Introduction. . . . . . . . . . . . . . . . . . . . . . . . .   4
       1.1.  Acronyms & Abbreviations. . . . . . . . . . . . . . . .   4
       1.2.  Multiple Types of Switching and Forwarding Hierarchies.   5
       1.3.  Extension of the MPLS Control Plane . . . . . . . . . .   7
       1.4.  GMPLS Key Extensions to MPLS-TE . . . . . . . . . . . .  10
   2.  Routing and Addressing Model. . . . . . . . . . . . . . . . .  11
       2.1.  Addressing of PSC and non-PSC layers. . . . . . . . . .  13
       2.2.  GMPLS Scalability Enhancements. . . . . . . . . . . . .  13
       2.3.  TE Extensions to IP Routing Protocols . . . . . . . . .  14
   3.  Unnumbered Links. . . . . . . . . . . . . . . . . . . . . . .  15
       3.1.  Unnumbered Forwarding Adjacencies . . . . . . . . . . .  16
   4.  Link Bundling . . . . . . . . . . . . . . . . . . . . . . . .  16
       4.1.  Restrictions on Bundling. . . . . . . . . . . . . . . .  17
       4.2.  Routing Considerations for Bundling . . . . . . . . . .  17
       4.3.  Signaling Considerations. . . . . . . . . . . . . . . .  18
             4.3.1.  Mechanism 1: Implicit Indication. . . . . . . .  18
             4.3.2.  Mechanism 2: Explicit Indication by Numbered
                     Interface ID. . . . . . . . . . . . . . . . . .  19
             4.3.3.  Mechanism 3: Explicit Indication by Unnumbered
                     Interface ID. . . . . . . . . . . . . . . . . .  19
       4.4.  Unnumbered Bundled Link . . . . . . . . . . . . . . . .  19
       4.5.  Forming Bundled Links . . . . . . . . . . . . . . . . .  20
   5.  Relationship with the UNI . . . . . . . . . . . . . . . . . .  20
       5.1.  Relationship with the OIF UNI . . . . . . . . . . . . .  21
       5.2.  Reachability across the UNI . . . . . . . . . . . . . .  21
   6.  Link Management . . . . . . . . . . . . . . . . . . . . . . .  22
       6.1.  Control Channel and Control Channel Management. . . . .  23
       6.2.  Link Property Correlation . . . . . . . . . . . . . . .  24
       6.3.  Link Connectivity Verification. . . . . . . . . . . . .  24
       6.4.  Fault Management. . . . . . . . . . . . . . . . . . . .  25
       6.5.  LMP for DWDM Optical Line Systems (OLSs). . . . . . . .  26
   7.  Generalized Signaling . . . . . . . . . . . . . . . . . . . .  27
       7.1.  Overview: How to Request an LSP . . . . . . . . . . . .  29
       7.2.  Generalized Label Request . . . . . . . . . . . . . . .  30
       7.3.  SONET/SDH Traffic Parameters. . . . . . . . . . . . . .  31
       7.4.  G.709 Traffic Parameters. . . . . . . . . . . . . . . .  32
       7.5.  Bandwidth Encoding. . . . . . . . . . . . . . . . . . .  33
       7.6.  Generalized Label . . . . . . . . . . . . . . . . . . .  34
       7.7.  Waveband Switching. . . . . . . . . . . . . . . . . . .  34
       7.8.  Label Suggestion by the Upstream. . . . . . . . . . . .  35
       7.9.  Label Restriction by the Upstream . . . . . . . . . . .  35
       7.10. Bi-directional LSP. . . . . . . . . . . . . . . . . . .  36