Last Call Review of draft-ietf-isis-route-preference-02
review-ietf-isis-route-preference-02-genart-lc-sparks-2015-10-27-00

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Document: draft-ietf-isis-route-preference
Reviewer: Robert Sparks
Review Date: 27Oct2015
IETF LC End Date: 30Oct2015
IESG Telechat date: Not yet scheduled

Summary: Ready for publication as Proposed Standard

This document reads easily despite most of it being detailed lists. I
have no objection to it moving forward, but I would like to check one thing:

The sparsity of detail at the end of section 2, where you call out
potential interoperability issues and suggest that "implementers may
wish to support transition mechanisms" is concerning.  It might be worth
being explicit here about the interoperability issues, and what a
transition mechanism might look like, particularly if there's a chance
of having to deal with a peer that won't implement what's described in
this draft?

Did the group consider defining a couple of new code points and
deprecating these two, to avoid that transition issue?