IMP Info

Latest things in Softwares,Freewares,Open Source,Internet,Programming…

Dovecot – Secure IMAP server

Posted by Parth Barot on January 6, 2006

Dovecot is an open source IMAP and POP3 server for Linux/UNIX-like systems, written with security primarily in mind. Although it’s written in C, it uses several coding techniques to avoid most of the common pitfalls.

Dovecot can work with standard mbox and maildir formats and it’s fully compatible with UW-IMAP and Courier IMAP servers’ implementation of them as well as mail clients accessing the mailboxes directly. It’s easy to migrate from them to Dovecot. I have also plans to support storing mails in SQL databases.

Dovecot is easy to set up and doesn’t require special maintenance. Only thing you need is to get the authentication working properly – if your users are in /etc/passwd there’s hardly anything you have to do.

Dovecot should be pretty fast. There are still some optimizations that could be done, but I believe it already beats most other IMAP servers in overall performance. This is mostly because of index files that Dovecot maintains; instead of having to scan through all the data in mailbox, Dovecot can get most of the wanted information from index with little effort. Dovecot’s indexes can scale to huge amount of messages per mailbox with hardly any noticeable slowdown. I’ve tested only up to 367000 mails, but millions of messages should be no problem.

Dovecot takes very little memory. Most of it goes to mmap()ed index and mailbox files, meaning that if operating system is low on memory, it can simply drop those memory pages without having to store them in swap. Connections are handled in separate processes, each one currently using around 100kB of swappable memory. Some extensions like SORT and THREAD will require more memory to work though.

More @


One Response to “Dovecot – Secure IMAP server”

  1. Wilco said

    Thank you very much for your post, you gave me some missing info i needed for my study

    I have bookmarked your site and hope to see more great stuff coming


    Wilco Breek

Sorry, the comment form is closed at this time.

%d bloggers like this: