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Liaison statement
Recent GMPLS and ASON-Related RFCs publ;ished

State Posted
Submitted Date 2007-02-21
From Group ccamp
From Contact Adrian Farrel
To Group ITU-T-SG-15
To Contacts Greg Jones <>
Cc Stephen Trowbridge <>
Kam Lam <>
Scott Bradner <>
Ross Callon <>
Deborah Brungard <>
Response Contact Adrian Farrel <>
Technical Contact Adrian Farrel <>
Purpose For information
Attachments (None)
The IETF's CCAMP working group is pleased to inform Study
Group 15 of the ITU-T of the publication of several new
RFCs that are relevant to the work that you are doing with
optical and packet transport networks. Several of these
RFCs received useful review and input from Study Group 15
participants for which CCAMP would like to express its

RFC 4558
   Node-ID Based Resource Reservation Protocol (RSVP)
   Hello: A Clarification Statement
   Use of Node-ID based Resource Reservation Protocol
   (RSVP) Hello messages is implied in a number of cases,
   e.g., when data and control planes are separated, when
   TE links are unnumbered.  Furthermore, when link level
   failure detection is performed by some means other than
   exchanging RSVP Hello messages, use of a Node-ID based
   Hello session is optimal for detecting signaling
   adjacency failure for Resource reSerVation Protocol-
   Traffic Engineering (RSVP-TE). Nonetheless, this implied
   behavior is unclear, and this document formalizes use of
   the Node-ID based RSVP Hello session in some scenarios.
   The procedure described in this document applies to both
   Multi-Protocol Label Switching (MPLS) and Generalized
   MPLS (GMPLS) capable nodes.

RFC 4652
   Evaluation of Existing Routing Protocols against
   Automatic Switched Optical Network (ASON) Routing
   The Generalized MPLS (GMPLS) suite of protocols has been
   defined to control different switching technologies as
   well as different applications.  These include support
   for requesting TDM connections including Synchronous
   Optical Network/Synchronous Digital Hierarchy
   (SONET/SDH) and Optical Transport Networks (OTNs).

   This document provides an evaluation of the IETF Routing
   Protocols against the routing requirements for an
   Automatically Switched Optical Network (ASON) as defined
   by ITU-T.

RFC 4726
   A Framework for Inter-Domain Multiprotocol Label
   Switching Traffic Engineering
   This document provides a framework for establishing and
   controlling Multiprotocol Label Switching (MPLS) and
   Generalized MPLS (GMPLS) Traffic Engineered (TE) Label
   Switched Paths (LSPs) in multi-domain networks.

   For the purposes of this document, a domain is
   considered to be any collection of network elements
   within a common sphere of address management or path
   computational responsibility.  Examples of such domains
   include Interior Gateway Protocol (IGP) areas and
   Autonomous Systems (ASes).

RFC 4736
   Reoptimization of Multiprotocol Label Switching (MPLS)
   Traffic Engineering (TE) Loosely Routed Label Switched
   Path (LSP)
   This document defines a mechanism for the reoptimization
   of loosely routed MPLS and GMPLS (Generalized
   Multiprotocol Label Switching) Traffic Engineering (TE)
   Label Switched Paths (LSPs) signaled with Resource
   Reservation Protocol Traffic Engineering (RSVP-TE).
   This document proposes a mechanism that allows a TE LSP
   head-end Label Switching Router (LSR) to trigger a new
   path re-evaluation on every hop that has a next hop
   defined as a loose or abstract hop and a mid-point LSR
   to signal to the head-end LSR that a better path exists
   (compared to the current path) or that the TE LSP must
   be reoptimized (because of maintenance required on the
   TE LSP path).  The proposed mechanism applies to the
   cases of intra- and inter-domain (Interior Gateway
   Protocol area (IGP area) or Autonomous System) packet
   and non-packet TE LSPs following a loosely routed path.

RFC 4783
   GMPLS - Communication of Alarm Information
   This document describes an extension to Generalized MPLS
   (Multi-Protocol Label Switching) signaling to support
   communication of alarm information.  GMPLS signaling
   already supports the control of alarm reporting, but not
   the communication of alarm information.  This document
   presents both a functional description and GMPLS-RSVP
   specifics of such an extension.  This document also
   proposes modification of the RSVP ERROR_SPEC object.

   This document updates RFC 3473, "Generalized Multi-
   Protocol Label Switching (GMPLS) Signaling Resource
   ReserVation Protocol-Traffic Engineering (RSVP-TE)
   Extensions", through the addition of new, optional
   protocol elements.  It does not change, and is fully
   backward compatible with, the procedures specified in
   RFC 3473.

All IETF RFCs can be downloaded for free from

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Adrian Farrel and Deborah Brungard
CCAMP Working Group chairs