Voice Agents

New page: SIP Wire Reference

New deep-dive page for SIP trunk integrators: SIP Wire Reference, linked from the SIP Trunking page.

It documents the exact wire contract, sourced from production packet captures: inbound and outbound call-flow ladders (including the digest-auth challenge on outbound), a real sanitised INVITE with its SDP, how each of your final responses is handled (what gets retried, what gets CANCELled), transfer semantics (a second outbound INVITE carrying X-Caller-ID, never SIP REFER, two channels per transferred call), the timer table (RTP keepalive, ringing, max duration), and how to debug with support using the SCL_ call ID that rides on the From tag of every INVITE we send.

The SIP Trunking troubleshooting section now also tells you to include that call ID in support tickets: every call that reaches us has a full capture on our side, and the ID is how support pulls it.