Resource Reservation Protocol (RSVP) Extensions for Path Key Support
RFC 5553

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 04

Network Working Group                                     A. Farrel, Ed.
Request for Comments: 5553                            Old Dog Consulting
Category: Standards Track                                    R. Bradford
                                                             JP. Vasseur
                                                     Cisco Systems, Inc.
                                                                May 2009

  Resource Reservation Protocol (RSVP) Extensions for Path Key Support

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) 2009 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
   Provisions Relating to IETF Documents in effect on the date of
   publication of this document (http://trustee.ietf.org/license-info).
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.

   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
   outside the IETF Standards Process, and derivative works of it may
   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.

Farrel, et al.              Standards Track                     [Page 1]
RFC 5553          RSVP Extensions for Path Key Support          May 2009

Abstract

   The paths taken by Multiprotocol Label Switching (MPLS) and
   Generalized MPLS (GMPLS) Traffic Engineering (TE) Label Switched
   Paths (LSPs) may be computed by Path Computation Elements (PCEs).
   Where the TE LSP crosses multiple domains, such as Autonomous Systems
   (ASes), the path may be computed by multiple PCEs that cooperate,
   with each responsible for computing a segment of the path.

   To preserve confidentiality of topology within each AS, the PCEs
   support a mechanism to hide the contents of a segment of a path (such
   as the segment of the path that traverses an AS), called the
   Confidential Path Segment (CPS), by encoding the contents as a Path
   Key Subobject (PKS) and embedding this subobject within the result of
   its path computation.

   This document describes how to carry Path Key Subobjects in the
   Resource Reservation Protocol (RSVP) Explicit Route Objects (EROs)
   and Record Route Objects (RROs) so as to facilitate confidentiality
   in the signaling of inter-domain TE LSPs.

1.  Introduction

   Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS)
   Traffic Engineering (TE) Label Switched Paths (LSPs) are signaled
   using the TE extensions to the Resource Reservation Protocol (RSVP-
   TE) [RFC3209], [RFC3473].  The routes followed by MPLS and GMPLS TE
   LSPs may be computed by Path Computation Elements (PCEs) [RFC4655].

   Where the TE LSP crosses multiple domains [RFC4726], such as
   Autonomous Systems (ASes), the path may be computed by multiple PCEs
   that cooperate, with each responsible for computing a segment of the
   path.  To preserve confidentiality of topology with each AS, the PCE
   Communications Protocol (PCEP) [RFC5440] supports a mechanism to hide
   the contents of a segment of a path, called the Confidential Path
   Segment (CPS), by encoding the contents as a Path Key Subobject (PKS)
   [RFC5520].

   This document defines RSVP-TE protocol extensions necessary to
   support the use of Path Key Subobjects in MPLS and GMPLS signaling by
   including them in Explicit Route Objects (EROs) and Record Route
   Object (RROs) so as to facilitate confidentiality in the signaling of
   inter-domain TE LSPs.

Farrel, et al.              Standards Track                     [Page 2]
RFC 5553          RSVP Extensions for Path Key Support          May 2009

1.1.  Conventions Used in This Document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

1.2.  Usage Scenario

   Figure 1 shows a simple network constructed of two ASes.  An LSP is
   desired from the ingress in AS-1 to the egress in AS-2.  As described