Re: Last Call: draft-daboo-srv-email (Use of SRV records for locating email services) to Proposed Standard

SM <sm@resistor.net> Fri, 18 September 2009 06:29 UTC

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Message-Id: <6.2.5.6.2.20090917221202.0320bb80@resistor.net>
Date: Thu, 17 Sep 2009 23:30:00 -0700
To: Cyrus Daboo <cyrus@daboo.name>
From: SM <sm@resistor.net>
Subject: Re: Last Call: draft-daboo-srv-email (Use of SRV records for locating email services) to Proposed Standard
In-Reply-To: <20090820143320.CAD283A68E0@core3.amsl.com>
References: <20090820143320.CAD283A68E0@core3.amsl.com>
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Hi Cyrus,
At 07:33 20-08-2009, The IESG wrote:
>The IESG has received a request from an individual submitter to consider
>the following document:
>
>- 'Use of SRV records for locating email services '
>    <draft-daboo-srv-email-02.txt> as a Proposed Standard

In the Introduction section:

   "A better approach would be to require
    miniml information to be entered by a user which would result in
    automatic configuration of appropriate services for that user."

There is a typo for "minimal".

In Section 4:

   "If the SRV lookup is successful the host name and port for
    the service can be determined and used to complete client
    configuration."

What happens if there is more than one service record for a SRV 
service type?  You provided an alternative in the case of POP3 and 
IMAP with the "it could prompt the user to make a choice, or pick one 
based on local policy".

In Section 5:

       "In the former case, the email
        addresses must not conflict with other forms of permitted user
        login name."

You could use "MUST NOT".

A discussion of the "domain name of the target host" (RFC 2782) may 
be helpful in this section as the it affects the current practice of 
using an alias as the host name for the service.

Quoting RFC 2782:

   "The SRV RR allows administrators to use several servers for a single
    domain, to move services from host to host with little fuss, and to
    designate some hosts as primary servers for a service and others as
    backups."

The mechanism in this proposal provides for automatic configuration 
of appropriate services to help the user.  However, service providers 
are restricted in their ability to move services from host to host 
with little fuss once the email client uses this one-off 
configuration mechanism.  The choice is between a simple automatic 
configuration mechanism of email clients or a service discovery 
protocol for email clients.

In Section 6:

   "Alternatively, if transport layer security is being used,
    clients MUST use the service domain used in the SRV record lookup as
    the server name for certificate verification pruposes."

There is a typo for "purposes".

Regards,
-sm

Re: Last Call: draft-daboo-srv-email (Use of SRV … SM