MBOX-Line: From mrc at CAC.Washington.EDU  Wed May 30 16:45:26 2007
To: imap-protocol@u.washington.edu
From: Mark Crispin <mrc@CAC.Washington.EDU>
Date: Fri Jun  8 12:34:39 2018
Subject: [Imap-protocol] Vista Mail doesn't handle \NoSelect mailboxes?
In-Reply-To: <1180567472.32181.2062.camel@hurina>
References: <alpine.OSX.0.99.0705301048240.11683@pangtzu.panda.com> 
	<20070530113546.Q27473@orthanc.ca>
	<alpine.WNT.0.99.0705301146290.5388@Shimo-Tomobiki.Panda.COM>
	<BF01B191-D34E-47DE-A4FB-EAF1CADE4715@apple.com>
	<1180563766.32181.2028.camel@hurina>
	<alpine.WNT.0.99.0705301555120.2080@Shimo-Tomobiki.Panda.COM>
	<1180567472.32181.2062.camel@hurina>
Message-ID: <alpine.OSX.0.99.0705301626140.13729@pangtzu.panda.com>

On Thu, 31 May 2007, Timo Sirainen wrote:
> I guess your view of how subscriptions should work differs significantly
> from how other people use them. I like that my subscription list is
> almost exactly like the full mailbox list. I've just removed a couple of
> mailboxes that I rarely want to look at.

How is it useful to have a subscription list that is little (or not at 
all) different than the full mailbox list?

Does your server export newsgroups?  Do you think it is useful that 
everybody's subscription list include all newsgroups by default?  If no, 
how do you reconcile that with your statement?

> What do you think then the subscriptions should be used for by people
> (or clients) who have only private mailboxes?

We have users with thousands of mailboxes, but only a relative handful 
(fewer than a dozen) that receive incoming messages.  All other mailboxes 
are archives, which receive messages that the user moved from some other 
mailbox.  The incoming messages mailboxes would be subscribed, and the 
archive mailboxes would not be.

Because of the abuse of IMAP subscriptions, we had to give up on using 
IMAP subscriptions.  Instead, we have to have ANOTHER list of mailboxes, 
in the Pine configuration, for incoming messages mailboxes.

This is my point.  Over the years, multiple people have complained that 
subscriptions are a useless part of IMAP.  I agree.  They *are* useless; 
not because they are less when used for the intended purpose, but because 
they were rendered useless by bad client implementations.

And it's all for no good reason.  The abuse provides no benefit.  It 
causes harm: most notably unnecessary RTTs and user complaints when 
subscription issues cause unexpected behavior.

Thanks to subscription abuse, on our new dual-use mailbox server, we are 
now obliged to make every single hierarchy level be a mailbox, even when 
it was intended to be a \NoSelect name, because Vista Mail won't allow 
access to children of any name that can't be subscribed.

>> I am starting to think that the solution is to remove subscriptions 
>> from IMAP entirely, and replace it with a mechanism to stores a list of 
>> IMAP URLs.
> What would be their purpose then?

The original purpose of subscriptions:

Identifying those mailboxes which receive incoming messages.

Identifying the public mailboxes (such as newsgroups) that the user wants 
to look at, as opposed to the tens of thousands of other public mailboxes 
that the user has no interest in.

Glue links to other mailboxes on IMAP servers.

-- Mark --

http://panda.com/mrc
Democracy is two wolves and a sheep deciding what to eat for lunch.
Liberty is a well-armed sheep contesting the vote.

