Table of Contents
Citadel is a highly integrated Groupware Platform with a AJAX-powered “Web 2.0” interface, but also providing SMTP, IMAP, POP3 and GroupDAV access to its content.
Citadel offers versatile email services with very low administration needed. It provides its own implementations of these server protocols: IMAP, POP3, SMTP, ManageSieve, XMPP, Citadel.
It is 100% free open source, its codebase is written mostly in C.
Feature list
- Email, calendaring, address books, bulletin boards, instant messaging, and more … all in one tightly integrated server package. Unlike other open source groupware systems, all of Citadel's data stores are built-in. All that tedious mucking about with dependencies and config files is a thing of the past.
- High-performance, multiprotocol, multithreaded server engine
- Wiki and blog engines built in. Citadel is a collaboration server and a content management system!
- Web browser, telnet/SSH, local client software accessible
- Standards-compliant e-mail built in: IMAP, POP3, ESMTP
- Group calendaring and scheduling (WebDAV, GroupDAV, and Kolab-1 compatible)
- Built-in listserv (mailing list server)
- Built-in RSS Feed Aggregation
- Integrated server-side mail sorting and filtering. Users can choose between an easy-to-use web based rules editor, or the power of writing complex scripts using the industry standard Sieve language.
- Database-driven, single-instance message store
- Built-in full text index for fast searching
- Authenticated SMTP for remote email submission
- Multiple domain support
- Built-in integration with perimiter email filtering technologies such as Realtime Blackhole Lists (RBL's), SpamAssassin, and ClamAV antivirus
- Server-to-server replication. Users in any number of domains can be spread out across any number of Citadel servers, allowing you to put data where you need it, and enabling infinite horizontal scalability.
- Web-based access to email, calendars, and everything else through a powerful AJAX-style front end
- Very strong support for “public folders” and message forums.
- Built-in instant messenger service
- SSL/TLS encryption for all protocols
- Citadel is true open source software. Unlike other groupware servers, it isn't a cut-down version of an expensive proprietary “pro” version. We make our very best work available to everyone on the same terms. 100% of our code is covered by the GNU General Public License (GPL3).
Provided Services
Mail Transfer Agent
- POP3 and IMAP (with optional SSL support)
- SMTP (with integrated auth mechanism)
Groupware/BBS Style Services
- Addressbook
- Calendar/Scheduling
- Filestorage
- Notes
- Tasks
- Wiki
- Blog
- XMPP/Jabber
Clients and Tools
- WebCit http interface for fullfeatured Groupware experience (as a standalone webserver)
- sendmail replacement
- Citadel console client (BBS style)
- 3rd party Outlook Connector
- 3rd party SyncML/OMA DS Funambol Server for syncing mobille devices
- also avaiable is a sendcommand for bash scripts or direct CLI usage
Requirements
- Berkeley DB (for internal data storage)
- GNU Conversion Library ( in order to support different languages)
- Expat
- Curl
- libical (Citadels own iCAL format)
- libsieve
Optional auth mechanisms
- OpenLDAP and Microsoft Active Directory
- PAM
- OpenSSL
Operating Systems
- All Linux flavours with an easy_install.sh
- Debian and Gentoo with dedicated .deb and .ebuild files
- Solaris and *BSD Systems work, too
Access
- HTTP: Firefox, Opera, Internet Explorer 7 and above
- KOLAB/GroupDAV: Thunderbird (with plugins), Evolution
- SyncML/OMA DS (optional): Android as of version 2.2, Symbian S60, Windows Mobile, iPhone and Blackberry devices are supported
Enhancements
- Nginx, Lighttpd or Apache as http proxies
- Postfix can be used for advanced mail setups
- ManageSieve