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Four projects, four roles
Read the role each project states. Do not treat them as four names for one PBX.
Learn in 5 minutes
- Place Asterisk, FreeSWITCH, Kamailio, and rtpengine
- Say which one is a media proxy meant to sit with Kamailio
- Refuse a single configuration that the pages do not share
Visual
Kamailio can sit in front of a PBX. rtpengine proxies the RTP. This drawing is that relationship, not a production size.
Worked example
Place the box Four lines. Pick the one that proxies RTP.
- Read each name.
- Match it to the page you would open.
- Pick the media proxy.
Fault
Calls reach Kamailio. Someone pastes an Asterisk dialplan into rtpengine and expects extensions to run.
The README defines rtpengine as a media proxy. Asterisk and FreeSWITCH document the dialplan.
Quiz
Ecosystem
Glossary, sister systems, and the integration seam for this room.
Workforce management WFM forecasts volume and builds schedules. It consumes contact-center events. It does not parse Via headers. When a forecast is wrong, the SIP symptom is usually queue delay and 480 or carrier congestion, not a broken dialog ID.
Sources and go deeper
- A brief history of the Asterisk project — last checked 2026-10
- Asterisk res_pjsip configuration — last checked 2026-10
- FreeSWITCH users manual — last checked 2026-10
- Kamailio SIP server — last checked 2026-10
- rtpengine README — last checked 2026-10