Protocol Action: 'IMAP4 Extension for returning STATUS information in extended LIST' to Proposed Standard

The IESG <iesg-secretary@ietf.org> Mon, 21 December 2009 19:03 UTC

From: The IESG <iesg-secretary@ietf.org>
To: IETF-Announce <ietf-announce@ietf.org>
Subject: Protocol Action: 'IMAP4 Extension for returning STATUS information in extended LIST' to Proposed Standard
Message-Id: <20091221190331.EC6513A6A87@core3.amsl.com>
Date: Mon, 21 Dec 2009 11:03:31 -0800
Cc: morg chair <morg-chairs@tools.ietf.org>, morg mailing list <morg@ietf.org>, Internet Architecture Board <iab@iab.org>, RFC Editor <rfc-editor@rfc-editor.org>
Precedence: list

The IESG has approved the following document:

- 'IMAP4 Extension for returning STATUS information in extended LIST '
   <draft-ietf-morg-status-in-list-01.txt> as a Proposed Standard


This document is the product of the Message Organization Working Group. 

The IESG contact persons are Lisa Dusseault and Alexey Melnikov.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-morg-status-in-list-01.txt

Technical Summary

Many IMAP clients display information about total number of
messages/total number of unseen messages in IMAP mailboxes.  In order
to do that they are forced to issue a LIST or LSUB command, to list
all available mailboxes, followed by a STATUS command for each mailbox
found.  This document provides an extension to LIST command that
allows the client to request STATUS information for mailboxes together
with other information typically returned by the LIST command.

Working Group Summary

There is concern that a client can adversely affect a mail server by
misusing this command in a situation with an extremely large number of
mailboxes, and/or where retrieving status information for the
mailboxes is very slow.  The reality, though, is that such clients
will already have the same effect by sending -- perhaps pipelining --
a very large number of STATUS commands.  This point is noted in the
Security Considerations.

Document Quality

Several server implementors and at least a few client implementors are
interested, and say they plan to implement this extension.  There's at
least one existing implementation, from Dovecot.  There has been
nothing of particular note related to reviews.

RFC Editor Note

Please shift [ACL] to be an informative reference.

Please remove the note at the top of page 2.

>> OLD
>>
>> 1. Conventions used in this document
>>
>>  In examples, "C:" indicates lines sent by a client that is connected
>>  to a server.  "S:" indicates lines sent by the server to the client.
>>
>>  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
>>  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
>>  document are to be interpreted as described in RFC 2119 [Kwds].
>>
>>
>> NEW
>>
>> 1. Introduction
>>
>>  Many IMAP clients display information about total number of messages/
>>  total number of unseen messages in IMAP mailboxes.  In order to do
>>  that they are forced to issue a LIST or LSUB command, to list all
>>  available mailboxes, followed by a STATUS command for each mailbox
>>  found.  This document provides an extension to LIST command that
>>  allows the client to request STATUS information for mailboxes
>>  together with other information typically returned by the LIST
>>  command.
>>
>> 1.1 Conventions used in this document
>>
>>  In examples, "C:" indicates lines sent by a client that is connected
>>  to a server.  "S:" indicates lines sent by the server to the client.
>>
>>  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
>>  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
>>  document are to be interpreted as described in RFC 2119 [Kwds].

Protocol Action: 'IMAP4 Extension for returning S… The IESG