[OSPF] TTZ discussion point

"Papadimitriou, Dimitri (Dimitri)" <dimitri.papadimitriou@alcatel-lucent.com> Sat, 04 August 2012 03:05 UTC

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From: "Papadimitriou, Dimitri (Dimitri)" <dimitri.papadimitriou@alcatel-lucent.com>
To: "ospf@ietf.org" <ospf@ietf.org>
Date: Sat, 04 Aug 2012 05:05:00 +0200
Thread-Topic: TTZ discussion point
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Subject: [OSPF] TTZ discussion point
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Hi all,

As part of the discussions during the OSPF WG meeting, the following comes imho as the bottomline of the discussion for what concerns TTZ: what is the potential gain  

  i) when TTZ is used as "replacement of" existing OSPF techniques (thus compared to multi-area/ABR)

  ii) when TTZ is used "in complement to" OSPF techniques (thus in addition to)

The answer should help determining whether current multi-area/ABR is "too heavy for what it brings" vs there is a "third routing level" required in OSPF to sustain large deployments. 

In the latter case, assuming that multi-area/ABR is still appropriate, the next question would be: is it more suited to look at different mechanism or re-use as much as possible the existing one e.g. "sub-ABR" ?

Opinions ? Comments ?

Thanks,
-dimitri.
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