The Kamailio® SIP server is a leading Open Source software for building SIP services such as a SIP proxy, SIP Presence Server, SIP location server and much more. With a rich configuration language, modularity and continuos development Kamailio is the choise for building enterprise as well as carrier solutions. Kamailio runs on Unix and Linux systems, ranging from embedded systems to large scale multi-core servers.

Kamailio is the result of over 10 years of development, in the SIP express router project, the Open SER project and the SIP Router project. Kamailio is the result of a merger of multiple projects, a collaboration process that started on November 4, 2008. To understand the meaning of Kamailio in the SIP please see the Kamailio SIP Router Releases pages.

Kamailio  is released under GNU Public License v2 (GPLv2). Beginning with 3.0.0, the application includes parts of code under BSD license that can be used such as individual components.

Kamailio  can be:

  • SIP proxy server
  • SIP registrar server
  • SIP location server
  • SIP application server
  • SIP dispatcher server
  • SIP Websocket server

A more detailed list of capabilities is available in features page

Kamailio  cannot be:

  • SIP phone
  • media server
  • back-to-back user agent

Get involved!

We invite individuals, academic institutes or companies to actively take part in the development of the project. It is not only about writing C code, you can help with:

  • code development – core, modules and adjacent applications
  • documentation – writing or enriching documentation
  • miscellaneous – different management tasks (e.g., web site maintenance)
  • ideas – new ideas bring brilliant solutions

Join our mailing lists, start using and contributing to the SIP server.

Evolution of the project over the time is summarized in History page.

You can get in contact with developers via public mailing lists and web forum.