Re: [dane] namespace management, DANE Client Authentication draft updated

Viktor Dukhovni <ietf-dane@dukhovni.org> Thu, 14 January 2016 01:19 UTC

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From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [dane] namespace management, DANE Client Authentication draft updated
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> On Jan 13, 2016, at 8:01 PM, John Levine <johnl@taugh.com> wrote:
> 
>> Because the client prefix-label a service *name*, so so the port
>> collision issue goes away.  We should not cargo-cult designs,
>> the rationale has to carry over logically, and false analogies
>> need to be avoided.
> 
> One man's cargo cult is another man's namespace management.  Every
> existing use of _<service> names is behind a _<proto> name, and there
> seems to me considerable merit to keep it that way, at the trivial
> cost of a possibly uninteresting _tcp or _udp in the name.  If the
> extra five bytes is an issue, I suppose we could use _c rather than
> _client for the client tag.
> 
> While saving five characters was a big deal when I was programming
> PDP-8's almost 50 years ago, I don't get it now.

This forces clients that use both TCP and UDP to publish their TLSA
records twice (or better publish one as a CNAME for the other, or
make both CNAMEs to a third thing).  Is this really worth it?

Folks are having a hard enough time publishing correct TLSA records,
and remembering to change all the copies.

-- 
	Viktor.