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

Peter Psenak <ppsenak@cisco.com> Wed, 18 July 2018 15:23 UTC

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Date: Wed, 18 Jul 2018 11:23:34 -0400
From: Peter Psenak <ppsenak@cisco.com>
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To: Uma Chunduri <uma.chunduri@huawei.com>, "Ketan Talaulikar (ketant)" <ketant@cisco.com>, "lsr@ietf.org" <lsr@ietf.org>
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Subject: Re: [Lsr] Concerns with draft-chunduri-lsr-isis-preferred-path-routing
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Hi Uma,

On 17/07/18 09:43 , Uma Chunduri wrote:
> Hi Peter,
>
>
> -----Original Message-----
> From: Peter Psenak [mailto:ppsenak@cisco.com]
> Sent: Tuesday, July 17, 2018 9:34 AM
> To: Uma Chunduri <uma.chunduri@huawei.com>; Ketan Talaulikar (ketant) <ketant@cisco.com>; lsr@ietf.org
> Cc: spring@ietf.org
> Subject: Re: [Lsr] Concerns with draft-chunduri-lsr-isis-preferred-path-routing
>
>
> 	> flex-algo is NOT a per path state. It's a regular prefix-SID, which is bound to a prefix only.
>
> Not quite. I will come back to this bit later.

please do so, as I don't know what do you mean by "Not quite".

>
> 	>The problem with your proposal is that you flood all paths to all routers in the area and ask every router to evaluate all of them and see which of them may apply. This scale poorly.
>
> Please see Section 6, in 01 version.

the section 6 points to a solution that does not exist as of yet. I can 
only comment once it is available, but the fact that you need an extra 
hooks to address the scalability just confirms the limited scaling 
property of the basic proposal.

thanks,
Peter

>
> --
> Uma C.
>
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