Subject: comments on draft-cheshire-ipv4-linklocal-00.txt

From: Donald Eastlake 3rd <[email-masked]>
Date: Wed, 31 May 2000 14:22:00 -0400

This generally looks good but I have the following comments:

(1) The draft says that DNS RRs giving a link local address SHOULD NOT
be returned in response to requests received fron non local addresses.
However, I think this is impractical.  DNS knows nothing about
different classes or numeric regions of addressing in "A" IPv4 RRs (or
in any of the IPv6 RRs either for that matter).  Even if it did, to
conditionally not return some A RRs while returning others would break
the DNS "RRset" concept which treats all RRs with the same name and
type as a unit (see RFC 2181, Resource Record Sets).  For example,
RRset's are the level at which signatures are done for DNS security
(see RFC 2535) so a signature can't be verified unless you have the
full RRset.

(2) I suppose it's too late, but wouldn't using 0xFFFE0000 through
0xFFFEFFFF to get a 2**16 link local address region have be a bit more
consistent with the general IPv4 address type scheme? Or possibly just
use Class E (0xF0000000 - 0xF7FFFFFF) and define Class F to start with
111110 binary...

(3) On random number generation in section 2, I recommend that you
simply reference RFC 1750.

(4) I believe an IPv6 host is required to be able to support multiple
addresses per interface, which you might mention in section 3.

Seems like this draft should be listed on the ZEROCONF WG charter page
so people interested in that can find it.  (The chairs can do that by
just sending a message to Steve Coya.  It does not require that the
draft be renamed.)

Thanks,
Donald
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