Telnyx

Telnyx SIP connections support multiple authentication methods based on network topology and security requirements.

Methods

Method	Description	Details
Credential-based	Username/password for SIP registration	See below
IP + Token	`X-Telnyx-Token` header with IP validation	Separate page
IP + Tech Prefix	4-digit prefix prepended to dial string	Separate page
IP + P-Charge-Info	Phone number in `P-Charge-Info` header	See below
FQDN	Hostname-based inbound routing	See below

Username and password for SIP registration. POST /v2/credential_connections

{
  "connection_name": "my-connection",
  "user_name": "username",
  "password": "secure-password"
}

For WebRTC applications requiring dynamic credentials or JWT tokens, see WebRTC Authentication.

SIP header containing a phone number associated with the connection.

P-Charge-Info: <sip:[email protected]>

Requires E.164 format. The number must be assigned to the connection.

Hostname-based inbound routing combined with credentials or IP authentication for outbound.

Inbound	Outbound
FQDN	Credentials
FQDN	IP address

Method	Inbound	Outbound	Dynamic IP	Static IP
Credentials	✓	✓	✓	✓
IP + Tech prefix	✓	✓	-	✓
IP + Token	✓	✓	-	✓
IP + P-Charge-Info	✓	✓	-	✓
FQDN + Credentials	✓	✓	✓	✓
FQDN + IP	✓	✓	-	✓