Linux Message Center

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The Linux Message Center is a complete mail solution designed for enterprise users. It consists of all essential components to build a mail server such as SMTP, IMAP and POP3 services. Furthermore a web interface to the mailboxes, a web-based administration tool and a LDAP server for storing account information is included in this package.



Our philosophy was to provide a solution, which is completely build on Open Source software. We used the best software available for the particular services:

  • Postfix (SMTP): Sending and receiving mail
  • Cyrus Imapd (IMAP/POP3): Mail storage
  • OpenLDAP (LDAP): Storing account information
  • Apache (HTTP): Web server
  • Squirrelmail: Web mail client
  • LMC Admin: web-based administration

Design Goals

We always kept an eye of our design goals. The implementation of the software components must be done with security and speed in mind. Furthermore it has to prove its reliability in various tests with many users. And through software is only good if it matches your needs, flexibility is a necessity.

System Structure

The mail handling (send and receive) is done through Postfix. If it receives a message, it queries the OpenLDAP server if the recipient of the mail exists on this server. If a match was found Postfix hand the message over to the Cyrus Imapd, which stores it in its internal message database. If a user checks his mail by using a traditional mail client, he must authenticate himself to the Cyrus Imapd. The user name and password are compared to strings, which are stored in the LDAP server and if the authentication was successful, the user has access to his mailbox through IMAP or POP3. The authentication and the data transfer can be encrypted. The access to the mail of an user over the web interface is similar and always encrypted.

Through the web-based administration interface, you can create, modify or delete user accounts. At the time of writing this introduction, it is relatively simple yet and you can not create such things as shared folders. For these you have to use the shell tools, but this will change soon.