[Lsr] draft-zhu-lsr-isis-sr-vtn-flexalgo

Peter Psenak <ppsenak@cisco.com> Tue, 09 March 2021 09:46 UTC

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From: Peter Psenak <ppsenak@cisco.com>
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Date: Tue, 09 Mar 2021 10:46:01 +0100
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Subject: [Lsr] draft-zhu-lsr-isis-sr-vtn-flexalgo
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Dear authors,

here are couple of comments to draft-zhu-lsr-isis-sr-vtn-flexalgo:

1. whether we want to flood VTN specific link data in IGPs or not is 
something that deserves its own discussion.

2. Nevertheless, the proposed encoding does not seem to be a fortunate one:

a) it hijacks the L2 bundle member TLV for VTN data. I don't see the 
need for that.

b) the proposed mechanism to associate the VTN specific link data with 
the VTN itself by the use of the link affinities is a very user 
unfriendly way of doing it. If the VTN need only the low latency 
optimization, provisioning additional affinities seems like a 
unnecessary provisioning price that would need to be paid by the user 
for the encoding deficiency. You want to flood the VTN specific link 
data, put the VTN ID in it.