Create a Telnyx SIP Connection and Outbound Voice Profile for SIP trunking

Steps

1. Log in to the Telnyx Mission Control Portal and navigate to SIP Trunking > SIP Connections; create a new SIP Connection, choosing either IP-based authentication (add your PBX source IP) or credential-based authentication (set a username and generate a credential).
2. Configure the connection's inbound settings: set the SIP URI subdomain (e.g., yourcompany.sip.telnyx.com) which your PBX will register to or use as a destination; enable the codecs your PBX supports (Telnyx supports G.711, G.722, Opus, and others).
3. Create an Outbound Voice Profile under Voice > Outbound: set a name, choose the traffic type (Conversational, Metered, etc.), and add the SIP Connection(s) that will use this profile for outbound calls.
4. Assign phone numbers to the SIP Connection via the Numbers section so that inbound PSTN calls to those numbers are delivered to your PBX via the connection.
5. Test inbound and outbound calling; for outbound, your PBX dials Telnyx's SIP termination address (provided in the portal) and includes the calling number in the From header matching a number on your account.
6. Use the Telnyx API (POST /sip_connections and POST /outbound_voice_profiles) to manage connections programmatically with YOUR_API_KEY in the Authorization header for CI/CD automation.