Re: [Lsr] [spring] Concerns with draft-chunduri-lsr-isis-preferred-path-routing

Uma Chunduri <> Tue, 17 July 2018 18:43 UTC

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From: Uma Chunduri <>
Date: Tue, 17 Jul 2018 14:43:38 -0400
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To: "Les Ginsberg (ginsberg)" <>
Cc: Uma Chunduri <>, "Peter Psenak (ppsenak)" <>, "Ketan Talaulikar (ketant)" <>, "" <>, "" <>
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Subject: Re: [Lsr] [spring] Concerns with draft-chunduri-lsr-isis-preferred-path-routing
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Les -



> Although I will certainly consider the additional response you seem to
> have hinted at in your reply to Peter, it seems to me that Section 6 of
> your draft acknowledges that there is a scaling problem

[Uma]:  What it says is there is no scale issue in certain deployments
where only limited number of pats are required (examples given).  In that
case you don't need any *further extensions* as referred.
              As we noted this is fully backward compatible for SR-MPLS and
SRH data planes and one can go ahead and use it one can't find a path and
SID depth is an issue (in terms of  any of these, HW compatibility, Line
rate, header tax or MTU).

> - and then references what seems to be a non-existent draft (I could not
> find "draft-ce-ppr-graph-00" ???) as a proposed solution.

[Uma]: This will be posted soon, few things are being worked out. This
helps in certain cases (you will see soon), where you want to scale
optimized paths.

> In any further response you make it would be good if you did indicate
> whether you agree PPR has a scaling issue -

[Uma]: Plz see above..

> Thanx.
>     Les