Subject: [dnsext] Re: adoption of draft-kerr-ixfr-only-01 as a work item for DNSEXT

From: Alfred Hönes <[email-masked]>
Date: Thu, 8 Apr 2010 15:15:30 +0200 (MESZ)

[[ changed Subject to make it more expressive ]]

Andrew Sullivan wrote:

> In any case, we have a request for adoption of draft-kerr-ixfr-only as
> a WG item.  I've noted some interest in the draft.  If at least five
> participants say they support adoption and commit to reviewing through
> WGLC, then we can agree to the request.
>
> Best regards,
>
> Andrew (as co-chair)

I *conditionally* support the ixfr-only proposal.

Background:

Given the approval of axfr-clarify for publication as an RFC and
discussions we had on AXFR over UDP (two year ago, rejected by the
WG), large parts of RFC 1995 have become aged and inappropriate.

RFC 1995 is based on the (non-)specification of AXFR in STD 13
and states two assumptions on AXFR that simply do not hold (or
do not hold any more) -- there is no scenario for AXFR where the
server responds with a single SOA record, and there is no need
for a SOA query *over UDP* before performing AXFR (over TCP).
Even worse, the RFC 1995 procedure apparently is incompatible
with the response verification rules laid down in the Forgery
Resilience document, RFC 5452; this IMHO makes the automatic
fallback from IXFR to AXFR rather questionable *in general*,
from a current point of view.  Further, I found a substantial
amount of editorial flaws in RFC 1995.

Thus, it seems of utmost priority to first provide an updated
specification for IXFR before starting work in the WG that is
based on this aged RFC.

Of course, the ixfr-only idea could be easily integrated with an
rfc1995-bis draft, and that should IMHO be the way to proceed.
This strategy would reduce the number of documents to work on and
avoid complicated document dependencies impeding advancement of
documents on the Standards Track.

Given the WGs decision to ban AXFR over UDP, the UDP part of IXFR
should be reconsidered, and it might indeed make sense to integrate
the idea of ixfr-only with the UPD-only part of IXFR.

Recently, I already had offered our chairs to help work on a
rfc1995-bis draft -- as soon as the AXFR RFC is out.

Technical detail:
Since ixfr-only needs EDNS anyway (for a new [extended] RCODE),
it should be considered to signal new behavior for IXFR (and allow
for additional feedback if necessary) via a new EDNS Option (for
use with IXFR only), thus avoiding the introduction of a new QTYPE.

Kind regards,
  Alfred.

-- 

+------------------------+--------------------------------------------+
| TR-Sys Alfred Hoenes   |  Alfred Hoenes   Dipl.-Math., Dipl.-Phys.  |
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