OpenSIPS
Open source SIP proxy/server for VoIP, video, IM, and presence.
1.5k stars 665 forks last commit first released
Actively maintained
Last commit 27 Jul 2026.
OpenSIPS is an Open Source SIP proxy/server that handles signaling for voice, video, IM, presence, and other SIP extensions. It is designed for carriers, ITSPs and enterprises, offering scalable routing, load balancing, and rich signaling features.
Key Features
- High-performance, multi-functional SIP signaling engine suitable for large-scale deployments.
- Modular architecture with pluggable modules for routing, security, presence, and application integration.
- Front-end load balancing, session routing, and versatile deployment options including SBC-like uses.
- TLS/SSL support for secure signaling via the tls_openssl module.
- Active project with official releases and packaging across platforms.
Use Cases
- Carrier/ITSP trunking and enterprise PBX-like deployments.
- Front-end load balancing for SIP signaling across clustered OpenSIPS instances.
- IMS-like deployments or enterprise applications requiring centralized signaling control.
Conclusion: OpenSIPS is a mature, open-source SIP signaling platform widely used by carriers and enterprises to build scalable, resilient SIP infrastructure. It benefits from a modular architecture, active development, and official packaging and releases.
Categories:
Tags:
Tech Stack:
Similar to OpenSIPS
Wazo Platform
Open-source programmable IP telecommunication platform
Open-source, API-first platform for carrier-grade IP communications: VoIP, WebRTC, messaging, conferencing and programmable telephony microservices.
Spectrum 2
Open-source instant messaging transport gateway for multiple IM networks
A protocol gateway that bridges users across different instant messaging networks using libpurple adapters, enabling cross-network chat and presence.
Flexisip
Modular C++ SIP server suite for VoIP, messaging, and conferencing
Open-source, modular SIP server (proxy, presence, conference, B2BUA) with push gateway, ICE/STUN/TURN, MySQL/SQLite support; optimized for mobile and embedded systems.
Jami
Distributed, open source communication platform for calls and messaging
Jami is a distributed communication platform for private messaging, audio/video calls, and conferencing, designed to work without central servers and with end-to-end encryption.
Mattermost
Secure, self-hosted team collaboration and messaging platform.
Open-source, self-hosted messaging platform for secure team collaboration with real-time chat, audio calls, screen sharing, and integrations.
Zammad
Web-based helpdesk and customer support ticketing system
Open source, web-based helpdesk for managing customer support tickets across multiple channels like email, chat, phone, and social media.