Do cyrus devs plan to implement PUSH-IMAP protocol?

[Greg Banks]

On 30/01/2012, at 19:59, "Georg C. F. Greve" <greve at kolabsys.com> wrote:

> On Monday 30 January 2012 12.12:52 crocket wrote:
>> Is there any plan to implement PUSH-IMAP in cyrus IMAP?
>
> Generally I'd be very interested in everything that improves  
> performance for
> mobile devices with IMAP, but in this case I notice that the drafts  
> went on a
> little longer, but then ultimately expired with draft 12, it seems:
>
>    https://tools.ietf.org/id/draft-maes-lemonade-p-imap-12.txt
>
> That draft seems to have expired in 2006 with no RFC as its result,  
> perhaps
> because in 2005 Nokia claimed to hold patents that apply to it:
>
>    https://datatracker.ietf.org/ipr/604/
>
> Whether these are among patents that was provided to the patent  
> trolls in the
> recent deals I do not know and did not check. [1]
>
> In any case, as the draft expired almost 6 years ago and never  
> turned into
> RFC, one wonders what Apple plans to do with this, which expired  
> draft version
> it plans to support, whether there will be proprietary extensions  
> and so on
> and so forth.

The state of push email on the iPhone seems quite confusing (in  
particular it seems the Apple documentation is contradictory or  
missing), but after some reading it seems that the iPhone supports  
three push email protocols:

- for Yahoo accounts, Yahoo's non-standard push protocol based on UDP

- for MobileMe accounts, Apple's non-standard push protocol based on  
XMPP

- for the Microsoft Exchange account (just the one per iPhone  
apparently), Microsoft's ActiveSync protocol. Google also uses this.

This information is more or less rumour. Perhaps somebody from Apple  
could clarify what the actual situation is?

But, on current information it seems the only way for a service which  
isn't Yahoo or Apple to achieve actual email push to a iPhone is to  
talk ActiveSync. This is presumably why the Google folks added  
ActiveSync support.

The original poster mentioned the Z-Sync project, which a PHP  
implementation of the ActiveSync serverside which can talk IMAP to a  
backend. Presumably that involves the Z-Sync server polling IMAP,  
which would be better than the client polling but still less than  
wonderful.

Given that the CMU guys have been adding http and XML support to Cyrus  
for CalDAV, some of the pieces that ActiveSync needs are coming  
anyway, so it's not entirely impossible to imagine some future Cyrus  
supporting ActiveSync directly.

Georg, I notice there's a page about Z-Sync on the Kolab wiki. Do you  
have any idea of the legal issues with the protocol?


>
> Personally I'd be strongly in favour of such technologies.

Me too; I work with an iOS device and a Cyrus server daily. Lots of  
our customers use iOS devices.

Greg.