A complete platform for mail and collaboration
In the enterprise email market, Microsoft Exchange dominates with an integrated ecosystem of email, calendar, contacts and tasks, tightly coupled with Outlook as the client. Open source alternatives exist — Postfix, Dovecot, SquirrelMail — but they are separate components requiring manual integration, system administration expertise and offering no comparable user experience.
Zimbra Collaboration Suite tackles the problem differently: building a single platform that integrates all communication and collaboration services, with a modern web interface and a complete backend, released as open source software under an MPL (Mozilla Public License) licence in its community edition.
The AJAX client
The most visible element of Zimbra is its AJAX web client, an interface that in 2006 represents the state of the art in web applications. Drag and drop, context menus, message previews, folder management — everything happens in the browser without reloading the page. The experience is comparable to a desktop client, in an era when most webmail services offer static interfaces based on simple HTML.
The client integrates email, a calendar with invitations and confirmations, contacts with a shared address book, tasks with deadlines and priorities and a briefcase for document sharing. Every component is interconnected: an email can generate an appointment, a contact can be linked to a task.
Integrated backend
The backend is written in Java and orchestrates a series of established open source services: Postfix as the MTA (Mail Transfer Agent), OpenLDAP for authentication and directory services, MySQL for metadata, Lucene for full-text search. The architecture is designed for horizontal scalability: multiple Zimbra servers can be configured in a cluster to handle thousands of mailboxes.
Administration takes place through a dedicated web console that manages domains, mailboxes, distribution lists, disk quotas, security policies and backups. Support for standard protocols — IMAP, POP3, SMTP, CalDAV, CardDAV — ensures compatibility with third-party clients.
The alternative to Exchange
Zimbra positions itself as the direct open source alternative to Microsoft Exchange: the same breadth of functionality, without licence costs for the community edition. For organisations that need a complete and internally controllable communication platform, Zimbra eliminates dependence on a single proprietary vendor while maintaining a level of integration and usability that individually assembled components cannot offer.
Link: zimbra.com