Interworking Requirements to Support Operation of MPLS-TE over GMPLS Networks
RFC 5146

Network Working Group                                     K. Kumaki, Ed.
Request for Comments: 5146                              KDDI Corporation
Category: Informational                                       March 2008

       Interworking Requirements to Support Operation of MPLS-TE
                          over GMPLS Networks

Status of This Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Abstract

   Operation of a Multiprotocol Label Switching (MPLS) traffic
   engineering (TE) network as a client network to a Generalized MPLS
   (GMPLS) network has enhanced operational capabilities compared to
   those provided by a coexistent protocol model (i.e., operation of
   MPLS-TE over an independently managed transport layer).

   The GMPLS network may be a packet or a non-packet network, and may
   itself be a multi-layer network supporting both packet and non-packet
   technologies.  An MPLS-TE Label Switched Path (LSP) originates and
   terminates on an MPLS Label Switching Router (LSR).  The GMPLS
   network provides transparent transport for the end-to-end MPLS-TE
   LSP.

   This document describes a framework and Service Provider requirements
   for operating MPLS-TE networks over GMPLS networks.

Kumaki                       Informational                      [Page 1]
RFC 5146         Operating MPLS-TE over GMPLS Networks        March 2008

Table of Contents

   1. Introduction ....................................................3
      1.1. Terminology ................................................4
   2. Reference Model .................................................4
   3. Detailed Requirements ...........................................5
      3.1. End-to-End Signaling .......................................5
      3.2. Triggered Establishment of GMPLS LSPs ......................5
      3.3. Diverse Paths for End-to-End MPLS-TE LSPs ..................6
      3.4. Advertisement of MPLS-TE Information via the GMPLS
           Network ....................................................6
      3.5. Selective Advertisement of MPLS-TE Information via
           a Border Node ..............................................6
      3.6. Interworking of MPLS-TE and GMPLS Protection ...............7
      3.7. Independent Failure Recovery and Reoptimization ............7
      3.8. Complexity and Risks .......................................7
      3.9. Scalability Considerations .................................7
      3.10. Performance Considerations ................................8
      3.11. Management Considerations .................................8
   4. Security Considerations .........................................8
   5. Recommended Solution Architecture ...............................9
      5.1. Use of Contiguous, Hierarchical, and Stitched LSPs ........10
      5.2. MPLS-TE Control Plane Connectivity ........................10
      5.3. Fast Reroute Protection ...................................10
      5.4. GMPLS LSP Advertisement ...................................11
      5.5. GMPLS Deployment Considerations ...........................11
   6. Acknowledgments ................................................11
   7. References .....................................................11
      7.1. Normative References ......................................11
      7.2. Informative References ....................................12
   8. Contributors' Addresses ........................................13

Kumaki                       Informational                      [Page 2]
RFC 5146         Operating MPLS-TE over GMPLS Networks        March 2008

1.  Introduction

   Multiprotocol Label Switching traffic engineering (MPLS-TE) networks
   are often deployed over transport networks such that the transport
   networks provide connectivity between the Label Switching Routers
   (LSRs) in the MPLS-TE network.  Increasingly, these transport
   networks are operated using a Generalized Multiprotocol Label
   Switching (GMPLS) control plane.  Label Switched Paths (LSPs) in the
   GMPLS network provide connectivity as virtual data links advertised
   as TE links in the MPLS-TE network.

   GMPLS protocols were developed as extensions to MPLS-TE protocols.
   MPLS-TE is limited to the control of packet switching networks, but
   GMPLS can also control technologies at layers one and two.

   The GMPLS network may be managed by an operator as a separate network
   (as it may have been when it was under management plane control
   before the use of GMPLS as a control plane), but optimizations of
   management and operation may be achieved by coordinating the use of
   the MPLS-TE and GMPLS networks and operating the two networks with a