Subject: Draft Liaison - ASON Routing Loop Prevention

From: "BRUNGARD, DEBORAH A, ATTLABS" <[email-masked]>
Date: Wed, 7 Nov 2007 15:48:33 -0600

Hi CCAMP,
 
We need to respond on ITU-T Q14/15's recent Liaison:
https://datatracker.ietf.org/liaison/370/
 
Here's a proposed response, appreciate any comments by Nov. 13.
 
Thanks,
Deborah
 
======================
 
To: ITU-T Q14/15

From: IETF CCAMP Working Group

Cc: Stephen Trowbridge, Kam Lam, Scott Bradner, Dave Ward, Ross Callon,
CCAMP Working Group

Subject: ASON Routing Loop Prevention

For Action

The IETF's CCAMP Working Group thanks you for your liaison entitled
"Liaison Statement to CCAMP on ASON Routing Loop Prevention" issued from
your Stuttgart interim meeting in September 2007.

Your understanding is correct, the Associated Area ID reflects the area
from which the routing information is received. For your example, it
would reflect C, not D. As the description in Section 6.3.1 of our draft
was misunderstood, we will add clarifications.

Thank you for flagging your concerns about reconfiguration scenarios. As
you say in your liaison, the frequency of reconfigurations that require
the change of Area ID is unlikely to be high, but we recognize the
importance of making sure such procedures can be followed without unduly
opening up scope for operator error and without causing excessive
configuration activity. In this respect, we have been guided by the
reorganization requirements set out in RFC 4258 and the evaluation
scenarios described in RFC 4652. As described in 6.3 of the draft, the
use of the Associated Area ID is only required in scenarios when more
than one RC is bound to an adjacent level of the hierarchy and both are
configured to redistribute routing information. As the operational
aspects remain a concern to you, we will add text to the draft to
further clarify aspects of OSPF operations for reorganization scenarios.

Please let us know of any remaining operational concerns.

Best regards,

Adrian Farrel and Deborah Brungard

IETF CCAMP Working Group Co-Chairs