Re: [Doh] [Ext] a tad confused on response sizes

Tony Finch <dot@dotat.at> Tue, 05 June 2018 15:07 UTC

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Date: Tue, 5 Jun 2018 16:07:42 +0100
From: Tony Finch <dot@dotat.at>
To: Paul Hoffman <paul.hoffman@icann.org>
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Subject: Re: [Doh] [Ext] a tad confused on response sizes
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Paul Hoffman <paul.hoffman@icann.org>; wrote:
> On Jun 5, 2018, at 7:17 AM, Tony Finch <dot@dotat.at>; wrote:
> >
> > Thinking about this further, I think this is a bug, because a DoH client
> > doesn't have any way to recover from TC.
>
> A non-DOH DNS client that can't get a TCP connection to the resolver
> open can't recover either.

That's not a supported configuration - RFC 7766.

> In both cases, the TC bit means "here's the best I got". 'Twas always thus.

No, TC means "I have more to tell you but it wouldn't fit in your buffer".

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>;  http://dotat.at/
Fisher: East 4 or 5, decreasing 2 or 3. Moderate or rough, occasionally slight
later. Mainly fair. Moderate or good.