How to connect Telnyx to VICIdial

To connect Telnyx to VICIdial you create a Telnyx SIP Connection, pick IP authentication or credential authentication, then add a SIP Carrier entry in VICIdial pointed at the Telnyx SIP domain. Telnyx supports both auth styles, so a static-IP box can use the simpler IP path.

Get the connection from Telnyx

In the Telnyx portal create a SIP Connection (the FQDN/IP-authenticated type). Telnyx gives you a SIP domain to dial against and lets you choose the authentication method. Pick IP Authentication and add your server's public IP as an Authentication IP, or pick Credentials and Telnyx mints a username and password. Buy a number and assign it to the connection for inbound traffic.

• Note the SIP domain Telnyx shows on the connection page; you dial out to it.
• Add your VICIdial server's public IP under the connection's IP authentication settings.
• Confirm the Codec list includes G.711 ulaw so your allow=ulaw line matches.

Add the carrier in VICIdial

Open Admin then Carriers then Add New Carrier. With IP auth you leave the register line blank and pin the host. With credential auth, put the Telnyx username and secret in the Registration string as register => user:pass@<telnyx-sip-domain>.

Account Entry:

• [telnyx] / disallow=all / allow=ulaw / type=friend / context=trunkinbound
• host=<your Telnyx SIP domain> / dtmfmode=rfc2833 (Telnyx prefers RFC 2833 DTMF)

Set Protocol to SIP. Telnyx expects E.164 dialing. With campaign dial prefix 9 on a US number, strip the 9 and prepend +1:

• exten => _91NXXNXXXXXX,1,AGI(agi://127.0.0.1:4577/call_log)
• exten => _91NXXNXXXXXX,2,Dial(SIP/telnyx/+${EXTEN:1},,tTor)

Set Server IP, set Active to Y, and save. Wait about a minute for the conf files to regenerate.

Set sane channel and codec limits

Telnyx caps how many simultaneous calls a connection will carry. Match that ceiling to how hard your campaign dials so you do not generate more Concurrent calls than the connection allows and start collecting 503 rejections. On the VICIdial side, keep disallow=all then allow=ulaw so every leg is plain G.711 and the carrier never has to transcode; if you also want G.729 to save bandwidth, add allow=g729 only when both ends support it.

Telnyx also offers a TLS/SRTP profile if you want the signaling and media encrypted. That is optional — most outbound dialing runs plain UDP on 5060 — but if you enable it on the Telnyx side you must mirror it in the Account Entry transport, or the peer will never come up.

The call path

sequenceDiagram
  participant V as VICIdial
  participant T as Telnyx SIP Connection
  participant P as PSTN
  V->>T: INVITE +1NXXNXXXXXX
  T->>P: route outbound
  P-->>T: answer
  T-->>V: 200 OK + RTP
  Note over V,T: inbound DID returns via trunkinbound

Verify it

Run sip show peers on the Asterisk CLI. An IP-auth peer reads OK/reachable; a credential peer reads Registered. Place a single test call from Campaign Detail, listen for clean RTP audio in both directions, and check the caller ID. Point a campaign at the trunk only after that test connects.

The end-to-end mechanism is in our VICIdial carrier integration guide, and the account block fields are broken down in the carrier account entry walkthrough.

A VICIfast box gets a fixed public IP and is live in under 40 seconds, so the Telnyx IP-auth path is a copy-paste of one address. See pricing to get started.