Liaison statement
Application of PCE to Inter-Layer Networks

Submission date 2007-11-20
From IETF PCE WG (Adrian Farrel)
To ITU-T Q12/15 and Q14/15 (Greg Jones)
Cc Stephen Trowbridge, Kam Lam, Malcolm Betts, Ross Callon, Dave Ward, Scott Bradner, PCE Working Group
Response contact Adrian Farrel, JP Vasseur
Technical contact Adrian Farrel, JP Vasseur
Purpose For information
Attachments (None)
The Path Computation Element (PCE) working group of the IETF is aware that 
your Questions have recently been discussing the inter-layer aspects of the 
ASON architecture and particularly how to select routes across a multi-layer 
network, and how to represent within a higher layer network the potential or 
real connectivity across a lower layer network.

In the light of G.7715.2 we believe that you may be interested in some work 
being discussed in the PCE working group. "Framework for PCE-Based 
Inter-Layer MPLS and GMPLS Traffic Engineering" may be found at 
This document should be read in the context of the general PCE architecture 
described in "A Path Computation Element (PCE)-Based Architecture"

Although not specifically targeted at the ASON architecture, we would 
welcome any comments that you have on 
draft-ietf-pce-inter-layer-frwk-05.txt, and invite interested parties to 
contribute either through the liaison process or via the PCE working group 
mailing list details of which can be found at the PCE working group charter 

We are also looking at the requirements driven by inter-layer routing for 
extensions to the PCE Protocol (PCEP) used for communication between Path 
Computation Clients (PCCs) and PCEs. These can be found in "PCC-PCE 
Communication and PCE Discovery Requirements for Inter-Layer Traffic 
Engineering "

Best regards,
JP Vasseur and Adrian Farrel
IETF PCE working group co-chairs