Re: [DNSOP] Fundamental ANAME problems

Mark Andrews <marka@isc.org> Mon, 05 November 2018 18:12 UTC

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From: Mark Andrews <marka@isc.org>
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Cc: =?utf-8?Q?M=C3=A5ns_Nilsson?= <mansaxel@besserwisser.org>, Tony Finch <dot@dotat.at>, "dnsop@ietf.org WG" <dnsop@ietf.org>, Brian Dickson <brian.peter.dickson@gmail.com>
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References: <CAH1iCirXYsYB3sAo8f1Jy-q4meLmQAPSFO-7x5idDufdT_unXQ@mail.gmail.com> <alpine.DEB.2.20.1811021543210.24450@grey.csi.cam.ac.uk> <20181105083526.GA12204@besserwisser.org> <7704C350-256A-42E3-B718-38FD449A2ADE@hopcount.ca>
To: Joe Abley <jabley@hopcount.ca>
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Subject: Re: [DNSOP] Fundamental ANAME problems
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People don’t want CNAME at the apex. They want a pointer to a server for a service at the apex.
CNAME provided a pointer to a server when the prefix was www. 

This can be done a number of ways.

1) Prefix  + name in rdata.
2) Service specific type + name in rdata. 
3) Generic type + service and name in rdata. 

This is DNS choices from the IAB. 

ANAME is a extremely complicated version of 2 for HTTP which may be morphed into 1 with a well known service name for other services but will always have the risk of being misinterpreted. 

There are much simpler ways to achieve 2 than ANAME for HTTP.
 
Mark
-- 
Mark Andrews