Re: [CCAMP] A question on draft-ietf-ccamp-rsvp-te-srlg-collect-01

"Zafar Ali (zali)" <zali@cisco.com> Mon, 03 December 2012 17:35 UTC

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From: "Zafar Ali (zali)" <zali@cisco.com>
To: Alan Davey <Alan.Davey@metaswitch.com>, "draft-ietf-ccamp-rsvp-te-srlg-collect@tools.ietf.org" <draft-ietf-ccamp-rsvp-te-srlg-collect@tools.ietf.org>
Thread-Topic: [CCAMP] A question on draft-ietf-ccamp-rsvp-te-srlg-collect-01
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Date: Mon, 03 Dec 2012 17:35:25 +0000
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Subject: Re: [CCAMP] A question on draft-ietf-ccamp-rsvp-te-srlg-collect-01
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Alan-

There are use cases where SRLGs for forward direction may not be same as SRLGs for reverse direction. E.g., consider a use case where an associated non-corouted tunnel is used as an FA; forward and reverse directions may follow different paths in the network. When such FA is used as a TE link for the tunnel for which SRLG recording is requested, forward and reverse SRLG values would be different.

Thanks

Regards...Zafar

From: ccamp-bounces@ietf.org [mailto:ccamp-bounces@ietf.org] On Behalf Of Alan Davey
Sent: Monday, December 03, 2012 12:23 PM
To: draft-ietf-ccamp-rsvp-te-srlg-collect@tools.ietf.org
Cc: ccamp@ietf.org
Subject: [CCAMP] A question on draft-ietf-ccamp-rsvp-te-srlg-collect-01

Authors

I have a doubt about draft-ietf-ccamp-rsvp-te-srlg-collect-01, specifically about the SRLG collection.  Could you please let me know what you think?

According to section 4.1, the collection of SRLG information in RROs for the Resv is different to that for the Path.  This is unlike the existing processing of RROs, which are handled in the same way for the upstream and downstream directions (as defined in RFC3209 section 4.4.3).  Can you please explain why the collection of SRLGs must be different in the different directions?  My preference is that SRLG information collection in RROs is handled in the same way as existing RRO processing.

Regards

Alan Davey


Network Technologies
Metaswitch Networks

alan.davey@metaswitch.com<mailto:alan.davey@metaswitch.com>
+44 (0) 20 8366 1177
network-technologies.metaswitch.com<http://network-technologies.metaswitch.com/>