Subject: CRH

From: Robert Raszuk <[email-masked]>
Date: Fri, 15 May 2020 12:48:13 +0200

Dear WG,

CRH at best seems to be just a building block (lego brick) on how to
accomplish yet one more solution for path engineering in a domain. Alone as
defined in the draft draft-bonica-6man-comp-rtg-hdr-NN it is pretty much
unusable.

Network operations require consistent mapping to function end to end. No
one sane would be using static configuration to plance IPv6 to SID mapping
along the paths.

Statements that CRH delivers path engineering alone and in its purity is
based on RFC8200 are not correct. It requires much more to be useful -
IGP/BGP extensions or dynamic state  imposition to the network elements in
a central manner. We have not seen other then SRm6 related to any document
how to take CRH as a building block and practically apply it in any
network.

Yet authors claim to cut themselves from any dependency on SRm6 that there
is zero relation to it.

Last but not least - how without dynamic routing extensions distributing
mapping domain wide - CRH based path engineering would propose to solve
TI-LFA or microloops avoidance problems ?

So putting any overlap between this proposal and SPRING WG aside IMO before
proceeding anywhere with CRH it should be required to see the full picture
(read architecture document) not just focus on one single element of it.

Kind regards,
Robert.