Graceful Shutdown in MPLS and Generalized MPLS Traffic Engineering Networks
RFC 5817

Internet Engineering Task Force (IETF)                            Z. Ali
Request for Comments: 5817                                   JP. Vasseur
Category: Informational                                        A. Zamfir
ISSN: 2070-1721                                      Cisco Systems, Inc.
                                                               J. Newton
                                                      Cable and Wireless
                                                              April 2010

             Graceful Shutdown in MPLS and Generalized MPLS
                      Traffic Engineering Networks

Abstract

   MPLS-TE Graceful Shutdown is a method for explicitly notifying the
   nodes in a Traffic Engineering (TE) enabled network that the TE
   capability on a link or on an entire Label Switching Router (LSR) is
   going to be disabled.  MPLS-TE graceful shutdown mechanisms are
   tailored toward addressing planned outage in the network.

   This document provides requirements and protocol mechanisms to reduce
   or eliminate traffic disruption in the event of a planned shutdown of
   a network resource.  These operations are equally applicable to both
   MPLS-TE and its Generalized MPLS (GMPLS) extensions.

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/rfc5817.

Ali, et al.                   Informational                     [Page 1]
RFC 5817                 MPLS Graceful Shutdown               April 2010

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
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   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
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   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

Table of Contents

   1. Introduction ....................................................3
   2. Terminology .....................................................3
   3. Requirements for Graceful Shutdown ..............................4
   4. Mechanisms for Graceful Shutdown ................................5
      4.1. OSPF / IS-IS Mechanisms for Graceful Shutdown ..............5
      4.2. RSVP-TE Signaling Mechanisms for Graceful Shutdown .........6
   5. Manageability Considerations ....................................8
   6. Security Considerations .........................................8
   7. Acknowledgments .................................................8
   8. References ......................................................9
      8.1. Normative References .......................................9
      8.2. Informative References .....................................9

Ali, et al.                   Informational                     [Page 2]
RFC 5817                 MPLS Graceful Shutdown               April 2010

1.  Introduction

   When outages in a network are planned (e.g., for maintenance
   purposes), some mechanisms can be used to avoid traffic disruption.
   This is in contrast with unplanned network element failure, where
   traffic disruption can be minimized thanks to recovery mechanisms,