“Zimlets” are inbuilt mini-applications that provide easily managed, modular user-customization. Users can choose to create “mashups” from ready made versions or custom Zimlets to suit their needs.
Users can create and share rich web documents including imbedded objects and attach versioning and last-modified information. These documents are saved into personal “notebooks”, which act as document repositories, and can be shared within the domain. The Briefcase application allows users to save documents in a wide variety of formats in folders which can be accessed remotely and shared with others, with users able to set permission levels for read or write access.
Zimbra’s role-based administration feature allows the administrator to delegate rights, as well as search across mailboxes, set mailbox and contacts quotas, and customize the interface. An impressive array of security features exist, such as message filtering, flags, anti-spam with configurable spam sensitivity, native antivirus with configurable virus signature update frequency, a system dashboard, and an ability to enforce SMPT authentication before relaying mail.
For support, the Zimbra forums contain 29,235 threads and 145,989 posts, with a very high level of reply. Ample documentation is also provided, which includes an installation manual, a massive 229 page end-user guide, and separate admin and how-to guides.
A major disadvantage of Zimbra is that, although it is compatible with most mobile web devices, the Open-source Edition doesn’t include the Standard Edition’s Connector for Outlook which enables full offline access to all shared and delegated folders.
Open Xchange – Appliance Edition
The award-winning Appliance Edition from Open-Xchange is a commercial web-based email and groupware solution aimed at small to medium sized businesses. The software has a strong following, a number of paid users totaling 8.4 million in 2008, quadrupling from the year before.
Like Zimbra, Open-Xchange has a tidy interface boasting high-level user interface features such as AJAX drag-and-drop, configurable views, and auto-complete. Advanced collaboration features allow users to share, delegate, set priorities and tasks, and measure progress. An “infostore” acts as a united document repository for the sharing of knowledge entries.
To extend the application, Open-Xchange uses UWA modules from Netvibes, which are external service tools similar to zimlets from Zimbra. If you’re interested in customizationor, like Zimbra, Open-Xchange is written in Java.
The software is protected by built-in antivirus and anti-spam functionality. Additionally, information sharing is filtered by identity, role-based management. Administration of this is made easy with a menu-based dashboard to manage groupware functions, users, groups and permissions.
With a self contained, menu-driven installation package, Open-Xchange states the software “can be installed in minutes” and can even be automated, as apposed to almost six hours for the eGroupWare package. Also included in the Appliance Edition is “OXtender” – an installer package to synchronize the software with Outlook. This enables offline access to e-mail, calendar, tasks, and contacts folders. Open-Xchange also works seamlessly with most modern smart-phones.
Documentation for the software is abundant, including a comprehensive FAQ section, a wiki, installation and user manuals, and a database of problem/solution articles. The Open-Xchange community forums hold little more than 11,000 posts, low compared to Zimbra and eGroupWare, but the rate of reply is very high. Support contracts are also available if necessary.
Open-Xchange provides a “future-proof upgrade assurance”, so there is no additional cost for maintenance, with a “data migration tool” included to facilitate the export and import of valuable data during upgrade processes. Finally, with regard to maintenance, the software’s “Bugzilla” application assists bug tracking, but no facility exists for public patch submission.
Zarafa is a workgroup sharing solution based on the look-and-feel of Microsoft Outlook. The software positions itself as a web-based substitute for Outlook, and consequently offers common features such as a soft-delete system to retrieve deleted emails after 30 days, and an out of office message. It has a slick interface which includes AJAX, split screen viewing, and drag and drop.
Zarafa has a convenient method for supporting groups. Directly below the main folder list are hyperlinks for accessing collaborative information in the form of shared folders or multi-user calendar. Providing quick and easy access, clicking the shared folders link produces a pop-up window of users of with public folders available. After selecting a user, all the public folders from that user are then added to your folder list. However, as it stands now, Zarafa only provides sharing services for emails, calendars and contacts, not documents, so offers limited options for collaboration.
For extension and configuration, Zarafa supplies no modular add-ons, like those of Zimbra and Open-Xchange. The software is written in PHP, suiting most developers. Zarafa provides a command-line administration tool used to manage users and groups, but without a graphical interface, administration of the Zarafa groupware could become cumbersome.
A drawback of the Zarafa software is that it does not include inbuilt antispam and antivirus protection, so, to ensure security, the groupware needs to be separately integrated with third-party antispam and antivirus software. Despite this, Zarafa allows connection to the server using HTTPS protocol, thus ensuring all connections over the network are encrypted before sending. Zarafa’s self-proclaimed unrivalled, stable Outlook sharing indicates easy integration with WebbingIt’s current desktop groupware, and as Zarafa utilizes “AirSync”, the software is also compatible with modern mobile devices.
The community forums contain only 13230 posts, but there is a high rate of reply. Documentation is sufficient, with plenty of manuals, a wiki, and separate whitepapers. However, regarding maintenance of the software, no public bug-tracking or patch submission facilities exist.
eGroupWare Enterprise Collaboration
Although the PHP web-based shareware package from eGroupWare lacks some of the view configuration and AJAX functionality of the other packages, it makes up for this by offering the widest range of collaboration structures.
To coordinate the sharing of the company’s know-how, included in a central repository is a searchable file manager, an “infolog”, which is a CRM-focused TODO list, and a shared FAQ application called Knowledgebase. A powerful calendar supports scheduling of groups, resources and contacts and, conveniently, a news section on the shareware’s homepage allows management to keep employees informed of recent developments. Significantly, eGroupWare is the only software of the group that includes project listing and tracking facilities to aid customer relationship and project management. This is a valuable feature for any company with project-based business processes.
eGroupWare can be synchronized easily with groupware modules synchronizing natively with Outlook and smart-phones via SyncML, although a review by Simple Thoughts website suggests that synchronization is not yet fully stable. As with Zarafa, the software lacks built in anti-virus and anti-spam, providing minimal security through email flagging and configurable message filtering, while the collaboration structures are guarded by user and group access rights management.
Documentation includes printed and online 180 page English manuals, and a detailed installation wiki. Support is available through an expansive forum with over 45,000 threads, although closer inspection reveals that the reply rate for posts is relatively low and most English threads are organized under only one category: Users. To help to maintain software reliability, the developers at eGroupWare maintain a changelog that is generated hourly, a prioritized bug-tracking system, and a patch manager application.
That’s all there is about open-source mailers and groupware. I hope it helped you to decide what’s right for you.