Asterisk
Open-source framework for building telephony systems
Asterisk is a widely used open-source PBX and telephony toolkit that powers IP PBX systems, VoIP gateways, and conferencing servers. It supports SIP, voicemail, IVR, and call queues.
Key features
- Full-featured IP PBX
- IVR and call queues
- Voicemail and conferencing
- SIP and PSTN connectivity
Strengths
- Released under the GPL-2.0 license
- First-class Docker support for quick deployment
- Active community (3.6k GitHub stars)
- Written in C
Asterisk replaces
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