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

Robert Edmonds <edmonds@mycre.ws> Tue, 14 February 2017 20:39 UTC

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Date: Tue, 14 Feb 2017 15:39:24 -0500
From: Robert Edmonds <edmonds@mycre.ws>
To: Ben Schwartz <bemasc@google.com>
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Subject: Re: [DNSOP] Proposal for a new record type: SNI
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Hi, Ben:

In your draft, the reason for not using TXT is given as:

2.1.3.  Using TXT

   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".

If you define "where the domain is found" as, e.g., domains like
_443._tcp._sni.www.example.com, then you get to define the semantics of
what is described by the TXT record at that location. I think DKIM is an
example of a protocol that uses this kind of scheme with TXT records.

-- 
Robert Edmonds