A Transport Network View of the Link Management Protocol (LMP)
RFC 4394
Network Working Group D. Fedyk
Request for Comments: 4394 O. Aboul-Magd
Category: Informational Nortel Networks
D. Brungard
AT&T
J. Lang
Sonos, Inc.
D. Papadimitriou
Alcatel
February 2006
A Transport Network View of the Link Management Protocol (LMP)
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.
Copyright Notice
Copyright (C) The Internet Society (2006).
Abstract
The Link Management Protocol (LMP) has been developed as part of the
Generalized MPLS (GMPLS) protocol suite to manage Traffic Engineering
(TE) resources and links. The GMPLS control plane (routing and
signaling) uses TE links for establishing Label Switched Paths
(LSPs). This memo describes the relationship of the LMP procedures
to 'discovery' as defined in the International Telecommunication
Union (ITU-T), and ongoing ITU-T work. This document provides an
overview of LMP in the context of the ITU-T Automatically Switched
Optical Networks (ASON) and transport network terminology and relates
it to the ITU-T discovery work to promote a common understanding for
progressing the work of IETF and ITU-T.
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RFC 4394 Transport Network View of LMP February 2006
Table of Contents
1. Introduction ....................................................2
2. ASON Terminology and Abbreviations Related to Discovery .........3
2.1. Terminology ................................................3
2.2. Abbreviations ..............................................4
3. Transport Network Architecture ..................................5
3.1. G.8080 Discovery Framework .................................7
4. Discovery Technologies ..........................................9
4.1. Generalized Automatic Discovery Techniques G.7714 ..........9
4.2. LMP and G.8080 Terminology Mapping .........................9
4.2.1. TE Link Definition and Scope .......................12
4.3. LMP and G.8080 Discovery Relationship .....................13
4.4. Comparing LMP and G.8080 ..................................14
5. Security Considerations ........................................15
6. Informative References .........................................15
7. Acknowledgements ...............................................16
1. Introduction
The GMPLS control plane consists of several building blocks as
described in [RFC3945]. The building blocks include signaling,
routing, and link management for establishing LSPs. For scalability
purposes, multiple physical resources can be combined to form a
single TE link for the purposes of path computation and GMPLS control
plane signaling.
As manual provisioning and management of these links are impractical
in large networks, LMP was specified to manage TE links. Two
mandatory management capabilities of LMP are control channel
management and TE link property correlation. Additional optional
capabilities include verifying physical connectivity and fault
management. [LMP] defines the messages and procedures for GMPLS TE
link management. [LMP-TEST] defines SONET/SDH-specific messages and
procedures for link verification.
ITU-T Recommendation G.8080 Amendment 1 [G.8080] defines control
plane discovery as two separate processes; one process occurs within
the transport plane space and the other process occurs within the
control plane space.
The ITU-T has developed Recommendation G.7714, "Generalized automatic
discovery techniques" [G.7714], defining the functional processes and
information exchange related to transport plane discovery aspects,
i.e., layer adjacency discovery and physical media adjacency
discovery. Specific methods and protocols are not defined in
Recommendation G.7714. ITU-T Recommendation G.7714.1, "Protocol for
automatic discovery in SDH and OTN networks" [G.7714.1], defines a
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RFC 4394 Transport Network View of LMP February 2006
protocol and procedure for transport plane layer adjacency discovery
(e.g., discovering the transport plane layer endpoint relationships
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