Early media and 183

Visual

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This ladder's 183 happens to carry SDP. 180 is ringing and has no SDP here. A 183 is allowed to omit SDP.

Worked example

183 has SDP, 180 does not Extract both responses. One progress message has SDP and the ringing message does not.

1. Press Extract SIP.
2. Open the 183 and look for m=.
3. Open the 180 and confirm there is no SDP.

Fault

The caller plays local ringback and a remote announcement at the same time.

RFC 3960 separates remote early media from local ringback. Playing both is the clipping and double-audio failure.

Quiz

Ecosystem

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

AI omni-channel agents A voice bot still needs a session. SIP creates, modifies, and ends sessions. Omni-channel, in the contact-center sense, means the same contact can also live on chat or another digital channel. Those channels do not replace the voice session. On Amazon Connect the platform owns the managed PSTN voice channel. Bridging an outside carrier into Connect with a Chime Voice Connector is not a supported pattern unless AWS reviews it. When an SBC forks the voice leg to a recorder, that fork is SIPREC, a different plane from the customer dialog.

AI agents A voice bot still needs a session. On Amazon Connect the platform owns the managed PSTN voice channel. Bridging an outside carrier into Connect with a Chime Voice Connector is not a supported pattern unless AWS reviews it. The FreeSWITCH manual page also describes SignalWire, founded by the FreeSWITCH team, as a hosted platform with AI agents behind REST APIs and SWML.

Glossary · Ecosystem map · Ports · Troubleshooting