Citadel is an integrated email and groupware server built around a room-based architecture. A single installation can provide conventional Internet email alongside calendars, contacts and several forms of online collaboration.
The server includes its own SMTP, IMAP and POP3 services rather than requiring separate mail-server components. Users can work through conventional mail clients or through the WebCit browser interface.
Citadel’s room model is used for mail folders, discussion areas and other shared content, providing a consistent approach to private and collaborative information.
This is free and open source software.
Key Features
- Built-in SMTP and ESMTP mail transport.
- IMAP and POP3 access for conventional email clients.
- WebCit browser-based interface.
- Calendars and address books.
- Forums and discussion areas.
- Mailing lists with individual-message and digest delivery.
- Multiple and virtual email domains.
- Users can have multiple email addresses across different domains.
- Instant messaging facilities.
- Wiki and blogging functionality.
- RSS aggregation.
- Room-based organisation of private and shared content.
- DKIM signing for outgoing email.
- Designed as a self-contained server without requiring a separate IMAP or SMTP package.
Website: www.citadel.org
Support:
Developer: Citadel.org
License: GNU General Public License v3.0
Citadel is written in C. Learn C with our recommended free books and free tutorials.
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