Z-Push

Last updated
Z-Push
Original author(s) Zarafa Deutschland GmbH
Developer(s) Z-Push Community
Stable release
2.7.1 [1]   OOjs UI icon edit-ltr-progressive.svg / 11 October 2023;4 months ago (11 October 2023)
Operating system Any
Platform Cross-platform
License AGPLv3
Website z-push.github.io

Z-Push (presumably Z is for Zarafa) is a FOSS implementation of the Microsoft Exchange ActiveSync protocol which is used to synchronize email, personal contacts and other items between a central server and a mobile device. [2]

Contents

Z-Push enables any PHP and non-PHP based groupware package to become fully sync-able with any ActiveSync compliant device with an appropriate backend.

Currently, Z-Push includes four backends: the IMAP and the Maildir backends for e-mail synchronization, the vCard and the CardDAV backends for contact synchronization, CalDAV for calendar synchronization, stickynotes for Sticky Notes Synchronization and one for the Kopano and Zarafa package which is sold by allowing full synchronization of E-mail, Calendar, Contacts, and Tasks. [3]

There is also a 3rd party project that implements a Zimbra Backend, allowing Z-Push to be used with a ZCS server (Including opensource edition). [4]

Since version 2.3.0, released in July 2016, significant performance improvements have been achieved, as well as significantly lower memory usage. Connecting to Outlook 2013 and 2016 via EAS is also officially supported. With the optional Kopano Outlook Extension (available only for paid subscribers of Zarafa/Kopano), additional Outlook features are enabled such as Out of Office replies and opening of shared and public folders. [5]

The future sustainability of the Z-Push project was in question after Kopano (formerly Zarafa) announced that they would no longer be supporting the project. [6] Z-Push now has a new maintainer from the community for future support of the project. [7]

Technical background and architecture

The ActiveSync protocol is a binary XML (WBXML) protocol across HTTP. The protocol is specifically designed with efficient use from mobile devices in mind. As such the protocol is optimized for low bandwidth, high latency connections. Also the protocol is designed for minimum number of whole request round trips. This means that the protocol can use many of the same techniques used to speed up access to websites. This is as opposed to IMAP or SMTP which is a two way handshaking TCP protocol which can be both quite slow and costly in terms of battery consumption across high latency connections. [8]

Getting ActiveSync instant push notification on mobile devices – particularly iOS devices – may well be the primary reason some people wish to use ActiveSync. However this will introduce significant additional server loading, so it should be carefully considered and monitored whether this is actually a desirable feature on the server.

The client (i.e. phone) uses long polling HTTP with 30 minute timeouts on the HTTP requests. This means if no mail arrives there is no traffic on the TCP channel and the phone radios remain in low power receive only mode. However, server-side these HTTP requests are served as long polling web requests and processed in PHP. When the request comes in it consumes the resources of a web request - see further discussion below - and keeps this open for up to 30 minutes, or until a new message arrives, or the client device is switched off. [8]

Related Research Articles

<span class="mw-page-title-main">Microsoft Outlook</span> Email and calendaring software

Microsoft Outlook is a personal information manager software system from Microsoft, available as a part of the Microsoft 365 software suites. Though primarily being popular as an email client for businesses, Outlook also includes functions such as calendaring, task managing, contact managing, note-taking, journal logging, web browsing, and RSS news aggregation.

SyncML is the former name for a platform-independent information synchronization standard. The project is currently referred to as Open Mobile Alliance Data Synchronization and Device Management. The purpose of SyncML is to offer an open standard as a replacement for existing data synchronization solutions, which have mostly been somewhat vendor-, application- or operating system specific. SyncML 1.0 specification was released on December 17, 2000, and 1.1 on February 26, 2002.

Messaging Application Programming Interface (MAPI) is an API for Microsoft Windows which allows programs to become email-aware. While MAPI is designed to be independent of the protocol, it is usually used to communicate with Microsoft Exchange Server.

<span class="mw-page-title-main">SOGo</span>

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Microsoft Exchange Server is a mail server and calendaring server developed by Microsoft. It runs exclusively on Windows Server operating systems.

<span class="mw-page-title-main">ActiveSync</span>

ActiveSync is a mobile data synchronization app developed by Microsoft, originally released in 1996. It synchronizes data with handheld devices and desktop computers. In the Windows Task Manager, the associated process is called wcescomm.exe.

Kolab is a free and open source groupware suite. It consists of the Kolab server and a wide variety of Kolab clients, including KDE PIM-Suite Kontact, Roundcube web frontend, Mozilla Thunderbird and Mozilla Lightning with SyncKolab extension and Microsoft Outlook with proprietary Kolab-Connector PlugIns.

<span class="mw-page-title-main">Zimbra</span> Collaborative software suite

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Push email is an email system that provides an always-on capability, in which when new email arrives at the mail delivery agent (MDA), it is immediately, actively transferred (pushed) by the MDA to the mail user agent (MUA), also called the email client, so that the end-user can see incoming email immediately. This is in contrast with systems that check for new incoming mail every so often, on a schedule. Email clients include smartphones and, less strictly, IMAP personal computer mail applications.

Push-IMAP, which is otherwise known as P-IMAP or Push extensions for Internet Message Access Protocol, is an email protocol designed as a faster way to synchronise a mobile device like a PDA or smartphone to an email server.

DeltaSync was a proprietary Microsoft communications protocol for synchronizing web services with offline clients. It was switched off by Microsoft on 30 June 2016.

<span class="mw-page-title-main">Zarafa (software)</span> Discontinued free and open-source groupware

Zarafa was an open-source groupware application that originated in the city of Delft in the Netherlands. The company that developed Zarafa, previously known as Connectux, is also called Zarafa. The Zarafa groupware provided email storage on the server side and offered its own Ajax-based mail client called WebAccess and a HTML5-based, WebApp. Advanced features were available in commercially supported versions. Zarafa has been superseded by Kopano.

RemoSync is a mobile application that provides corporate email, calendar, and contact synchronization for mobile phones capable of running BREW applications. Conceived as a low-cost alternative to BlackBerry or iPhone devices, RemoSync is currently available on the Verizon wireless network.

Exchange ActiveSync is a proprietary protocol designed for the synchronization of email, contacts, calendar, tasks, and notes from a messaging server to a smartphone or other mobile devices. The protocol also provides mobile device management and policy controls. The protocol is based on XML. The mobile device communicates over HTTP or HTTPS.

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A comparison of CalDAV and CardDAV implementations offers two overviews of client and server computer software implementations of the CalDAV and CardDAV protocols.

Kopano is an open-source groupware application suite originally based on Zarafa. The initial version of Kopano Core (KC) was forked from the then-current release of Zarafa Collaboration Platform, and superseded ZCP in terms of lineage as ZCP switched to maintenance mode with patches flowing from KC. Kopano WebApp similarly descended from Zarafa WebApp. Since October 2017, Kopano Core is also known more specifically as Kopano Groupware Core, since Kopano B.V. developed more products that were not directly requiring groupware components.

The JSON Meta Application Protocol (JMAP) is a set of related open Internet Standard protocols for handling email. JMAP is implemented using JSON APIs over HTTP and has been developed as an alternative to IMAP/SMTP and proprietary email APIs such as Gmail and Outlook. Additional protocols and data models being built on top of the core of JMAP for handling contacts and calendar synchronization are meant to be potential replacements for CardDAV and CalDAV, and other support is currently in the works.

References

  1. "Z-Push 2.7.1 final released".
  2. "Z-Push | Open source push technology" . Retrieved 2023-05-31.
  3. "Z-Push/src/backend at develop · Z-Hub/Z-Push". GitHub. Retrieved 2023-05-31.
  4. "Z-Push Zimbra Backend". SourceForge. 2023-05-13. Retrieved 2023-05-31.
  5. Bartels, Felix (2016-08-11). "Introducing the Kopano Outlook Extension -" . Retrieved 2023-05-31.
  6. "Statement regarding the community project Z-Push". 20 October 2022. Retrieved 23 November 2022.
  7. Bytemine (2023-04-25). "Z-Push has a new home and a new maintainer -" . Retrieved 2023-05-31.
  8. 1 2 "Z-Push (ActiveSync)". netwinsite.com. Retrieved 2023-05-31.