Zimbra Collaboration Suite (ZCS) is a groupware product created by Zimbra, Inc., located in
The ZCS Web Client is a full-featured collaboration suite that supports email and group calendars using an
The ZCS Server uses several open source projects (see the section, Included open source projects). It exposes a SOAP application programming interface to all its functionality and also is an IMAP and POP3 server. The server runs on many distributions of Linux as well as on Mac OS X.
ZCS is compatible with proprietary clients such as Microsoft Outlook and Apple Mail, both through proprietary connectors, as well as the open-source Novell Evolution, so that mail, contacts, and calendar items can be synchronised from these to the ZCS server. Zimbra also provides native two-way sync to many mobile devices (Nokia Eseries, BlackBerry, Windows Mobile, iPhone with 2.0 software).
imbra Collaboration Suite (ZCS) source code is available under the terms of the Yahoo! Public License (YPL) which is derived from the Mozilla Public License (MPL), and accordingly requires that modifications made to existing files, if distributed, be provided in source code form to the recipients under the same license. It also includes a clause requiring trademarks, logos, etc be preserved making it an "attribution-style" open source license.
Categorically it is similar to the Open Source Initiative (OSI) Common Public Attribution License (CPAL). Attribution-style open source licenses are a newer trend in recent years; and though now embraced by the OSI are not without some controversy. Some believe they may violate sections of the Open Source Definition and abuse the term "open source" while others believe they enable overall growth of the open source movement by allowing "commercial open source" companies (SugarCRM, Socialtext, Zimbra) to compete with proprietary ones in the enterprise.
Included open source projects
The ZCS Server utilizes open source projects such as:
Postfix
MySQL
OpenLDAP
Apache Tomcat (replaced by Jetty since 5.0)
Lucene
Verity
ClamAV
SpamAssassin
AMaViS and Amavisd-new
DSPAM
Aspell
James
Sieve
Perdition mail retrieval proxy (until 4.5)
nginx (since 5.0)