Re: [DNSOP] Proposal for a new record type: SNI

"John Levine" <johnl@taugh.com> Tue, 14 February 2017 22:19 UTC

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Date: 14 Feb 2017 22:19:25 -0000
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From: "John Levine" <johnl@taugh.com>
To: dnsop@ietf.org
In-Reply-To: <20170214203924.5c4v6l5b3bjipcfw@mycre.ws>
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Cc: edmonds@mycre.ws
Subject: Re: [DNSOP] Proposal for a new record type: SNI
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In article <20170214203924.5c4v6l5b3bjipcfw@mycre.ws> you write:
>   We could encode this information in a TXT record, but that would
>   violate the intended purpose of TXT records: to convey information to
>   human readers.
>
>I'm not sure if it's true that TXT records are intended only for human
>consumption. TXT RRs contain "descriptive text" where "[t]he semantics
>of the text depends on the domain where it is found".

That horse left the barn at least a decade ago, before SPF, DKIM,
DMARC, and a lot of other TXT records primarily intended to be
consumed by computers.  Humans can read them, but this human can't do
much with records like this:

taugh.com. IN TXT "google-site-verification=7SCAvuZtE7dOCpG0drHDEBOqco9JnPzFUIUBSgU3eWc"

Whether to use a TXT record is of course a subsidiary question to
whether DNS SNI indirection is a good idea in the first place.

R's,
John