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rtpengine and the integration map

rtpengine proxies RTP, rewrites SDP, and can bridge ICE and SRTP. It runs on GNU/Linux and is meant to sit with Kamailio.

Learn in 5 minutes

  1. List media features the README states
  2. Draw the SIP server beside the media proxy
  3. Keep kernel forwarding as an optimization the README describes

Visual

SIP on Kamailio, RTP toward rtpengine · study drawing · cyphermonkeylabs.com PhoneKamailiortpengine INVITE offer answer 200

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SIP stays on Kamailio. RTP can be forwarded by rtpengine, in kernel or in userspace.

Worked example

Read the rewritten c= line The offer points at the phone. The answer points at the proxy. That is the anchoring idea.

  1. Negotiate.
  2. Compare c=.
  3. Say which address the caller will send RTP toward.

Fault

The kernel module failed to load. RTP still flows. An alarm says rtpengine is dead because kernel forwarding is off.

Fallback to userspace is a documented behavior, not proof the process exited.

Quiz

rtpengine proxies


The supported platform named in the README is


In-kernel forwarding


ICE support in the README includes


SRTP support includes


SDP rewriting is available


Ecosystem

Glossary, sister systems, and the integration seam for this room.

CRM Screen pop uses data the contact center already has: ANI, DNIS, case id. Those values may arrive in SIP headers or in a CTI event after the call is up. The CRM is not a SIP element.

Glossary · Ecosystem map · Ports · Troubleshooting

Sources and go deeper