SIP Trunking

A SIP Trunk connects Teler to your own SIP infrastructure (a PBX, SBC, softswitch, or an AI voice platform) over SIP. It defines how Teler authenticates and routes SIP calls to and from that infrastructure, in both directions: inbound origination and outbound termination.

Trunks are created and managed in the Teler dashboard.

Tip

Use a Voice App when you want Teler to answer a number and run a programmable Call Flow you host. Use a SIP Trunk when you want to interconnect Teler with your own SIP system. They’re independent paths, and you can run both from the same account.

Configure a trunk

Click Create Trunk in the dashboard and fill in these fields:

Field	Required	Description
Name	yes	Internal label shown in the dashboard. Example: Production Trunk.
Domain Name	yes	Unique subdomain assigned to the trunk. All outbound calls route to this domain (a.k.a. the Termination URL). Alphanumeric and hyphens only.
Call Status URL	no	HTTPS endpoint that receives webhook events.
Secret	no	Signing secret used for HMAC signatures on webhooks. Rotatable without downtime.
Channel Limit	no	Maximum concurrent calls. Defaults to 0; purchase more as needed.
Recording	no	When enabled, all call audio is recorded and delivered via recording events.
Secure Mode	no	Controls transport encryption. See below.
Webhook API version	no	Pin the webhook payload shape to 2025-08-01 or 2026-06-01. See API versioning.

Secure Mode

Controls encryption for SIP signaling and media:

Mode	Signaling	Media
Enabled	SIP over TLS	SRTP
Disabled	SIP over TCP	RTP

TLS + SRTP is recommended for any trunk carrying customer PII.

Outbound authentication

Every trunk authenticates outbound calls one of two ways:

Method	Use when	How it’s configured
IP	Calls originate from fixed, static IP addresses.	List up to 5 IPs in the dashboard. Calls from those IPs are accepted without credentials.
Credential	Your SIP system authenticates via username and password.	Set the username and password in the dashboard; your SIP client presents them on each INVITE.

Caution

IP authentication is not suitable for dynamic or cloud-based environments where your SIP client’s egress IP may change. Prefer credential authentication in those cases.

Inbound routing

Inbound routing tells Teler where to deliver calls that arrive on the trunk. Configure a route with:

Field	Required	Description
Name	yes	Internal label for the route.
SIP URL	yes	The SIP URL where Teler should forward inbound calls (a.k.a. the Origination URL). Provided by your downstream platform (AI provider, PBX, SBC, or softswitch). Example: sip:sip.rtc.elevenlabs.io:5061.
SIP User	no	SIP username to present to the destination, if your downstream platform requires one.

Next steps

Network requirements Teler IP addresses, ports, and protocols to allow on your firewall.

Call events Lifecycle webhooks delivered to your Call Status URL.

API versioning Pin your trunk to 2025-08-01 or 2026-06-01.

Signing & verification HMAC-SHA256 signature verification for the trunk's webhook secret.