From: The IESG <firstname.lastname@example.org>
To: IETF-Announce <email@example.com>
Cc: Internet Architecture Board <firstname.lastname@example.org>,
RFC Editor <email@example.com>,
pce mailing list <firstname.lastname@example.org>,
pce chair <email@example.com>
Subject: Document Action: 'The use of SVEC (Synchronization VECtor) list for Synchronized dependent path computations' to Informational RFC
The IESG has approved the following document:
- 'The use of SVEC (Synchronization VECtor) list for Synchronized
dependent path computations '
<draft-ietf-pce-pcep-svec-list-05.txt> as an Informational RFC
This document is the product of the Path Computation Element Working Group.
The IESG contact persons are Adrian Farrel and Stewart Bryant.
A URL of this Internet-Draft is:
A Path Computation Element (PCE) performing dependent path
computations, for instance calculating a diverse working and
protected path not sharing common network points, would need to
synchronize the computations in order to increase the probability of
meeting the working and protected path diversity (or disjointness)
objective and network resource optimization objective. When a PCE
computes multiple sets of dependent path computation requests
concurrently, it is required to use Synchronization VECtor (SVEC)
list for association among the sets of dependent path computation
requests. SVEC is also applicable to end-to-end diverse path
computation across multiple domains. This document describes the
usage of SVECs in the SVEC list and diverse path computation
guideline, for the synchronized computation of dependent paths.
Working Group Summary
This document is informational, explaining the detail of existing
protocol mechanisms to achieve specific functions. There is at
least one implementation that we are aware of that makes use of
the mechanisms described here.
JP Vasseur (firstname.lastname@example.org) is the Document Shepherd.
Adrian Farrel (email@example.com) is the Responsible AD.
RFC Editor Note
Please expand "SRLG" as "Shared Risk Link Group"
If the PCE does not have capability to handle the associated SVEC
objects, it may send a PCErr message with Error-Type="Capability not
If the PCE, which is unable to handle the associated SVEC, finds
the common request-IDs in multiple SVEC objects, the PCE should
cancel the path computation request and respond to the PCC with
the PCErr message Error-Type="Capability not supported".
If a PCC sends path computation requests to a PCE and then sends
another path computation requests, which are dependent on the first
requests and has been associated by using a SVEC list.
However, if a PCC sends path computation requests to a PCE, and then
sends a further path computation request to a different PCE using the
SVEC list to show that the further request is dependent on the first
requests, there is no method for the PCE to correlate the dependent
requests sent to different PCEs.
Please expand "BRPC" as "Backward Recursive Path Computation"