Technical Summary
The Generic Associated Channel (G-ACh) has been defined as a
generalization of the pseudowire (PW) associated control channel to
enable the realization of a control/communication channel associated
with Multiprotocol Label Switching (MPLS) Label Switched Paths
(LSPs), MPLS PWs, MPLS LSP segments, and MPLS sections between
adjacent MPLS-capable devices.
This document describes how the G-ACh may be used to provide the
infrastructure that forms part of the Management Communication
Network (MCN) and a Signaling Communication Network (SCN).
Collectively, the MCN and SCN may be referred to as the Data
Communication Network (DCN). This document explains how MCN and SCN
messages are encapsulated, carried on the G-ACh, and demultiplexed
for delivery to the management or signaling/routing control plane
components on an MPLS-TP node.
It should be noted that the use of the G-ACh to provide connectivity
for the DCN is intended for use only where the MPLS-TP network is not
capable of encapsulating or delivering native DCN messages.
Working Group Summary
The document is part of the MPLS-TP project, the cooperation
between IETF and ITU-T to specify an MPLS transport profile.
The working group has consensus on the document, and the ITU-T
has indicated that it supports the publication.
Document Quality
We have seen test implementations of the G-ACh and received
feedback, but we know of no current implementations of the MCC
or SCC. We have been informed by two vendors of their intent to
implement soon. The document review has been substantial.
Considerable input to early revisions was received from MPLS WG
participants, from participants in the MPLS-TP project. The WG
last call was liaised to the ITU-T, and the final revision
(including resolution to WG last call comments) was supported by
the ITU-T in a liaison.(see PROTO writeup by Loa Andersson in the
ID tracker).
Personnel
Loa Andersson is the Document Shepherd. Ross Callon is the
responsible area director.
RFC Editor Note
Section 4
OLD
The G-ACh provides a virtual link between MPLS-TP nodes and might be
used to induce many forms of security attack. Protocols that operate
over the MCN or SCN are REQUIRED to include adequate security
mechanisms and implementations MUST allow operators to configure the
use of those mechanisms.
NEW
The G-ACh provides a virtual link between MPLS-TP nodes and might be
used to induce many forms of security attack. The MPLS data plane
does not include any security mechanisms of its own, therefore it is
important that protocols using the DCN apply their own security.
Protocols that operate over the MCN or SCN are REQUIRED to include
adequate security mechanisms and implementations MUST allow operators
to configure the use of those mechanisms.
END