MBOX-Line: From dave at cridland.net  Fri Mar 16 17:01:20 2007
To: imap-protocol@u.washington.edu
From: Dave Cridland <dave@cridland.net>
Date: Fri Jun  8 12:34:38 2018
Subject: [Imap-protocol] what IMAP extensions to implement?
In-Reply-To: <alpine.WNT.0.83.0703161613040.1748@Tomobiki-Cho.CAC.Washington.EDU>
References: <07Mar16.123633pst."57996"@synergy1.parc.xerox.com>
	<alpine.WNT.0.83.0703161613040.1748@Tomobiki-Cho.CAC.Washington.EDU>
Message-ID: <14682.1174089680.264752@invsysm1>

On Fri Mar 16 23:29:37 2007, Mark Crispin wrote:
> On Fri, 16 Mar 2007, Bill Janssen wrote:
>> I'm looking for recommendations as to what extensions make sense to
>> implement in my server.  Generally speaking, this is a mix of 
>> adding
>> true functionality and reasonably wide-spread client support.  I've
>> already added IDLE and NAMESPACE; what else makes sense?
> 
> Going through the current set of standards-track and approved (SORT 
> and THREAD are both blocked on i18n) extensions:
> 
> must-have:	LOGINDISABLED, STARTTLS
>  ;; requirement of the specification
> 
> should-have:	MULTIAPPEND, SORT, THREAD, UIDPLUS
>  ;; some clients are heavily impacted if absent
> 
> ought-to-have:	BINARY, IDLE, UNSELECT
>  ;; some clients are impacted if absent
> 
> nice-to-have:	CATENATE, CHILDREN, CONDSTORE, ESEARCH, LITERAL+,
> 		 NAMESPACE, SASL-IR, URLAUTH
>  ;; some clients will benefit if present; note that CATENATE and
>  ;; URLAUTH are part of the mandatory "trio" for Lemonade
> 
> 
I'd push NAMESPACE upward - clients using NAMESPACE at all are 
sometimes heavily impacted if this isn't available, and many will use 
it for some form of autoconfiguration.


> if meaningful:	ACL, LOGIN-REFERRALS, MAILBOX-REFERRALS, QUOTA
>  ;; may not be meaningful on your server
> 
> 
I'd put both ACL and QUOTA as nice-to-have - clients such as 
Thunderbird support ACL, and QUOTA is fairly common. That said, both 
are most often used in a read-only manner, and it's entirely legal to 
implement both on the server in a read-only way. Annoyingly, 
Thunderbird will generate errors if it cannot perform GETACL, so for 
ACL, you need both MYRIGHTS and GETACL.

Dave.
-- 
Dave Cridland - mailto:dave@cridland.net - xmpp:dwd@jabber.org
  - acap://acap.dave.cridland.net/byowner/user/dwd/bookmarks/
  - http://dave.cridland.net/
Infotrope Polymer - ACAP, IMAP, ESMTP, and Lemonade

