Subject: [v6ops] Adam Roach's No Objection on draft-ietf-v6ops-v4v6-xlat-prefix-02: (with COMMENT)

From: Adam Roach <[email-masked]>
Date: Wed, 21 Jun 2017 15:17:38 -0700

Adam Roach has entered the following ballot position for
draft-ietf-v6ops-v4v6-xlat-prefix-02: No Objection

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COMMENT:
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Like Suresh, I really appreciated the discussion of rationale in section 4.
There is one possibility that I'm surprised is not discussed; namely,
allocating 64::ff9b::/48 for this purpose, with the subset of addresses in
64::ff9b::/96 being *additionally* subject to the restrictions of RFC 6052.
This would seem to have the advantages of:

- Complete address adjacency without the disadvantages of using
64:ff9a:ffff::/48 - Sharing an even longer prefix (48 bits) than the 31-bit and
47-bit prefixes discussed in the document - Eliminating the caveat described in
the final paragraph of section 5 entirely

This is obvious enough that it had to be considered and rejected by the WG;
including the rationale for rejecting it seems appropriate here.