Re: [DNSOP] Clarification question: compression pointers always to names earlier in the packet?

George Michaelson <ggm@algebras.org> Thu, 25 October 2018 03:22 UTC

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From: George Michaelson <ggm@algebras.org>
Date: Thu, 25 Oct 2018 13:21:52 +1000
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To: muks@mukund.org
Cc: Ted Lemon <mellon@fugue.com>, Shane Kerr <shane@time-travellers.org>, dnsop WG <dnsop@ietf.org>
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Subject: Re: [DNSOP] Clarification question: compression pointers always to names earlier in the packet?
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As long as we're in UDP, with DNSSEC, and many NS, packetsize in DNS
will be a "thing" and revoking label compression pushes to fragments
and/or TCP.

Personally, I think TCP is fine, and the emergence of long-lived
bindings in DNS is fine, and this is a bit overblown as a problem.
But, I get reminded by people just how long, deep and *old* the CPE
embedded DNS footprint is. Which believes UDP at 512 is a "thing"

So basically, yes: you can turn it off. But. Is it wise?

-G