OpenSIPS is a mature SIP server designed for professional VoIP and real-time communications platforms.
It combines core SIP signaling and routing with a large set of modules for registration, call handling, presence, load balancing, NAT traversal, security, database connectivity, and external integrations, making it suitable for building scalable communication services and SIP infrastructure.
This is free and open source software.
Key Features
- Modular architecture with support for SIP registrar, transaction handling, dialog management, back-to-back user agent logic, and call center functionality.
- Advanced SIP routing capabilities including dispatcher, dynamic routing and least-cost routing, quality-based routing, and call load balancing.
- Support for NAT traversal, topology hiding, STIR/SHAKEN, SIP message operations, and presence services.
- Extensible scripting environment with Python, Lua, and Perl integration, plus JSON, XML, SQL, regex, and utility modules.
- Broad data-store support through SQL modules and CacheDB backends for systems such as Cassandra, Couchbase, Memcached, MongoDB, Redis, and SQL databases.
- External integration modules for embedded HTTP services, management interfaces, RabbitMQ, Kafka, RTPengine, RTPproxy, and FreeSWITCH.
- Infrastructure support for clustering and multiple transports including UDP, TCP, TLS, WebSocket, and secure WebSocket.
Website: github.com/OpenSIPS/opensips
Support:
Developer: OpenSIPS Project
License: GNU General Public License v2.0
OpenSIPS is written in C. Learn C with our recommended free books and free tutorials.
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Read our verdict in the software roundup.
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