Re: [DNSOP] DNSOP Call for Adoption: draft-kristoff-dnsop-dns-tcp-requirements

Tony Finch <dot@dotat.at> Fri, 12 May 2017 10:41 UTC

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Date: Fri, 12 May 2017 11:35:26 +0100
From: Tony Finch <dot@dotat.at>
To: 神明達哉 <jinmei@wide.ad.jp>
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Subject: Re: [DNSOP] DNSOP Call for Adoption: draft-kristoff-dnsop-dns-tcp-requirements
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神明達哉 <jinmei@wide.ad.jp> wrote:
>
>   I'm not sure if DDNS update bolsters the need for TCP.  In
>   my understanding DDNS update exchanges are largely done over UDP
>   today (e.g., ISC's nsupdate utility uses UDP by default):

Well, that depends on the transaction size :-) My servers fairly
frequently handle updates containing hundreds or records.

And `nsupdate` basically assumes that TCP is available - it doesn't give
the caller a way to find out what the server's maximum update size is.
(Similarly, my `nsupdate` wrapper `nsdiff` also assumes transactions can
be up to 64KB in size.)

So I think you'll be sad if you try to deploy an UPDATE server without TCP.

Tony.
-- 
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