» Releasing OpenSIPS 2.4.0 LTS - 30th of April 2018 The latest stable LTS release for the 2.4 major version, code-named The Cluster Maker.  » The OpenSIPS Summit - 1st - 4th of May 2018, in Amsterdam, NL Four days of presentations, demos, round tables and design clinics for and by the FOSS developers and community from various VoIP & RTC projects. Check our speakers and papers!  » Trainings for FreeSWITCH & OpenSIPS @ Summit - 4st of May 2018 Don't miss the first certified FreeSWITCH training ever run in Europe.

OpenSIPS is an Open Source SIP proxy/server for voice, video, IM, presence and any other SIP extensions.

OpenSIPS is a multi-functional, multi-purpose signaling SIP server used by carriers, telecoms or ITSPs for solutions like Class4/5 Residential Platforms, Trunking / Wholesale, Enterprise / Virtual PBX Solutions, Session Border Controllers, Application Servers, Front-End Load Balancers, IMS Platforms, Call Centers, and many others - see the full Set of Features.

OpenSIPS is recommended for any kind of SIP scenario / service by:

• the high throughput - tens of thousands of CPS, millions of ‏simultaneous calls (see official tests)
• the flexibility of routing and integration - routing script for implementing custom routing logics, several interfacing APIs (see the Manual)
• the effective application building - more than 120 modules to provide features, for SIP handling, for backend operations, for integration, for routing logics (see List of Modules)

Latest News...

Clustering Presence Services with OpenSIPS 2.4
27th of March 2018 Use presence clustering support to distribute and secure your data by implementing High Availability, Load Balancing or Federating scenarios. Read more...

Clustering ongoing calls with OpenSIPS 2.4
23rd of March 2018 Use dialog clustering to achieve High Availability and Load Balancing for your calls in setups as active-backup, active-active or anycast based. Read more...

Full Anycast support in OpenSIPS 2.4
21th of March 2018 Learn how you can do a full anycast scenario using OpenSIPS 2.4 Read more...

Scaling, Distributing and Partitioning Registrations with OpenSIPS 2.4
15th of March 2018 Everything about the upcoming usrloc change-storm in OpenSIPS 2.4 Read more...

The new Clustering Engine of OpenSIPS 2.4
13th of March 2018 Check the enhancements done in the clustering engine in OpenSIPS 2.4 - there are some interesting new concepts that are used for more complex clustering scenarios! Read more...

Announcing the Speakers and Papers for OpenSIPS Summit 2018
16th of February 2018 The Call for Papers is ended, resulting in 33 speakers and 29 exiting papers covering different topics. Check the list and join the Summit! Read more...

Two training sessions, two projects, one event – OpenSIPS Summit 2018
6th of February 2018 Along the OpenSIPS training, Amsterdam will host the first certified FreeSWITCH training in Europe ever. Read more...

How To Script Advanced FreeSWITCH Integrations with OpenSIPS 2.4
17th of January 2018 Latest FreeSWITCH integration enhancements--what they are and what we can build with them Read more...

Releases...

Major release: OpenSIPS 2.4.0 beta
28th of Mar 2018 A new major step in OpenSIPS evolution - the 2.4 branch is now ready with the OpenSIPS 2.4.0 beta released! Read more...

Minor releases: OpenSIPS 2.3.3 and 2.2.6
17th of Jan 2018 After several months of bug fixes, two new releases are nnow out: OpenSIPS 2.3.3 and 2.2.6! Read more...

Minor release: OpenSIPS 2.3.2
31st of Aug 2017 A new OpenSIPS 2.3 version featuring major fixes has been released! Read more...

Minor release: OpenSIPS 2.3.1 and 2.2.5
5th of Jul 2017 All releases contain important fixes, so upgrade your installs as soon as you can! Read more...

Minor release: OpenSIPS 2.2.4 and 1.11.11
18th of May 2017 All releases contain important fixes, so upgrade your installs as soon as you can! Read more...

Major release: OpenSIPS 2.3.0
26th of Apr 2017 After several fixes and improvements, we've finally released the latest OpenSIPS 2.3 stable version! Read more...