Subject: RE: Some Queries

From: "Martin, Christian" <[email-masked]>
Date: Tue, 9 Jan 2001 16:26:35 -0500

Thanks for the clarification, Kireeti.

> "Fixed metric" means that the LSP's metric doesn't change, even if
> it re-routes.  One of Vijay's problems is that a topology change could
> cause serious traffic shifts (to use his colorful language, slosh),
> negating the carefully constructed TE patterns and associated 
> bandwidths.

Agreed.  So you would still design meaningful metrics.  I was thinking fixed
relative to the other LSPs.  Sounds like an IP/IGP over ATM/PNNI topology!
I was looking at it from an edge to core perspective, neglecting to
recognize the end-to-end thrashing that would occur due to SPT changes in
the core.  After more reflection, it is clear that SPF churn would occur
regardless, but traffic flows would be stable.

Regards,
chris

> Kireeti.

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From: Kireeti Kompella <[email-masked]>
Date: Tue, 9 Jan 2001 13:39:06 -0800 (PST)

> Sounds like an IP/IGP over ATM/PNNI topology!

You got it! :-)

Kireeti.