PJSIP
lastmod 2026-11-10created 2019-01-102 edits
PJSIP is an open-source multimedia communication library written in C that bundles SIP signaling, RTP media transport, audio and video codecs, and NAT traversal (ICE, STUN, TURN). It is designed to be small and highly portable so that it runs on embedded devices and mobile, and its high-level API, PJSUA, makes it relatively easy to build a softphone. It is offered under both the GPL and a commercial license.