FreeSWITCH is an open-source software-defined telecom stack for building VoIP and real-time communication services with SIP and WebRTC support.
5.1k stars1.8k forkslast commit Actively maintained
5 self-hosted Metaswitch (Alianza) alternatives
Cloud-native telecom platform for communication service providers providing cloud-hosted VoIP/IP-PBX, IMS/core network functions, session control, SBC, and hosted voice/unified communications features for carrier-grade SIP calling, numbering and interconnect.
Alternatives to Metaswitch (Alianza)
#2
Open-source PBX and telephony toolkit for building communications applications; modular C-based engine with SIP, WebRTC, RTP, ARI/AMI APIs and hardware support.
3.5k stars1.3k forkslast commit Actively maintained
#3
Kamailio is an open source SIP signaling server for scalable VoIP and real-time communication platforms, supporting routing, load balancing, WebRTC, and IMS/VoLTE.
2.9k stars1.1k forkslast commit Actively maintained
#4
Routr is a programmable SIP server (proxy/registrar/location) for building scalable VoIP infrastructure with APIs, multi-tenancy, and Kubernetes-ready deployment.
1.7k stars179 forksMITlast commit Actively maintained
Carrier-grade VoIP softswitch/SBC for routing, billing, and managing SIP traffic, with LCR, fraud control, and high-availability deployment options.
Activity unknown
What replacing Metaswitch (Alianza) actually involves
Every option on this page is open source and free to run on your own hardware, so you own the data and there is no subscription to cancel. 4 of 5 shipped a commit in the last six months. Licences in this list: MIT. In exchange you take on hosting, backups and updates yourself.
Browse everything in VoIP / SIP & PBX.
