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Re: [DNSOP] Prefixed name spaces and DANE client TLSA

Tony Finch <dot@dotat.at> Wed, 13 January 2016 10:24 UTC

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Date: Wed, 13 Jan 2016 10:24:31 +0000
From: Tony Finch <dot@dotat.at>
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To: John Levine <johnl@taugh.com>
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Subject: Re: [DNSOP] Prefixed name spaces and DANE client TLSA
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John Levine <johnl@taugh.com> wrote:
>
> What's peculiar is the names.  The previous proposal was to look up a
> TLSA at _smtp.outbound.example.com, then somone noted that _smtp is
> for servers, so they want to look up the newly invented name
> _smtp-client.outbound.example.com.  If you have a client for some
> other service, you make up a name.  (Read the draft if this seems like
> an implausible summary.)

This naming scheme is a bad idea because it looks very similar to XMPP SRV
records but has confusingly different semantics.

_xmpp-client refers to an XMPP server endpoint for use by clients.
_xmpp-server refers to an XMPP server endpoint for use by other servers.

_submission refers to SMTP-like server endpoints for use by clients.
_smtp-client is proposed to refer to SMTP client initiators.

More generally this promises to clutter up the service identifier
namespace with identifiers for clients, which are not services.

I like the idea of taking the server's service labels and prefixing
them with _client.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>  http://dotat.at/
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