Framework for MPLS-TE to GMPLS Migration
RFC 5145

Network Working Group                                   K. Shiomoto, Ed.
Request for Comments: 5145                                           NTT
Category: Informational                                       March 2008

                Framework for MPLS-TE to GMPLS Migration

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

   The migration from Multiprotocol Label Switching (MPLS) Traffic
   Engineering (TE) to Generalized MPLS (GMPLS) is the process of
   evolving an MPLS-TE control plane to a GMPLS control plane.  An
   appropriate migration strategy will be selected based on various
   factors including the service provider's network deployment plan,
   customer demand, and operational policy.

   This document presents several migration models and strategies for
   migrating from MPLS-TE to GMPLS.  In the course of migration, MPLS-TE
   and GMPLS devices, or networks, may coexist that may require
   interworking between MPLS-TE and GMPLS protocols.  Aspects of the
   required interworking are discussed as it will influence the choice
   of a migration strategy.  This framework document provides a
   migration toolkit to aid the operator in selection of an appropriate
   strategy.

   This framework document also lists a set of solutions that may aid in
   interworking, and highlights a set of potential issues.

Shiomoto                     Informational                      [Page 1]
RFC 5145        Framework for MPLS-TE to GMPLS Migration      March 2008

Table of Contents

   1. Introduction ....................................................3
   2. Conventions Used in This Document ...............................3
   3. Motivations for Migration .......................................4
   4. MPLS to GMPLS Migration Models ..................................5
      4.1. Island Model ...............................................5
           4.1.1. Balanced Islands ....................................6
           4.1.2. Unbalanced Islands ..................................6
      4.2. Integrated Model ...........................................7
      4.3. Phased Model ...............................................8
   5. Migration Strategies and Toolkit ................................8
      5.1. Migration Toolkit ..........................................9
           5.1.1. Layered Networks ....................................9
           5.1.2. Routing Interworking ...............................11
           5.1.3. Signaling Interworking .............................12
           5.1.4. Path Computation Element ...........................13
   6. Manageability Considerations ...................................13
      6.1. Control of Function and Policy ............................13
      6.2. Information and Data Models ...............................14
      6.3. Liveness Detection and Monitoring .........................14
      6.4. Verifying Correct Operation ...............................14
      6.5. Requirements on Other Protocols and Functional
           Components ................................................14
      6.6. Impact on Network Operation ...............................15
      6.7. Other Considerations ......................................15
   7. Security Considerations ........................................15
   8. Acknowledgements ...............................................16
   9. References .....................................................16
      9.1. Normative References ......................................16
      9.2. Informative References ....................................17
   10. Contributors' Addresses .......................................17

Shiomoto                     Informational                      [Page 2]
RFC 5145        Framework for MPLS-TE to GMPLS Migration      March 2008

1.  Introduction

   Multiprotocol Label Switching Traffic Engineering (MPLS-TE) to
   Generalized MPLS (GMPLS) migration is the process of evolving an
   MPLS-TE-based control plane to a GMPLS-based control plane.  The
   network under consideration for migration is, therefore, a
   packet-switching network.

   There are several motivations for such migration, mainly the desire
   to take advantage of new features and functions added to the GMPLS
   protocols, which are not present in MPLS-TE for packet networks.
   Additionally, before migrating a packet-switching network from
   MPLS-TE to GMPLS, one may choose to first migrate a lower-layer
   network with no control plane (e.g., controlled by a management
   plane) to using a GMPLS control plane.  This may lead to the desire
   for MPLS-TE/GMPLS (transport network) interworking to provide