SIP credentials

SignalWire’s platform handles SIP with two complementary features:

• A SIP Credential is a SignalWire Resource that represents a SIP identity and controls how that identity places outbound calls.
• A Resource SIP Address is a unique SIP address you can assign to any Resource so that all inbound SIP calls are handled by that resource.

Used together, they provide a way to send SIP traffic to SignalWire and run your own logic on it.

SIP Credentials

A SIP Credential gives you a SIP address of the form sip:username@your-space.sip.signalwire.com and a password that SIP devices use to register with SignalWire.

Create a SIP Credential under Resources in your SignalWire Dashboard, or programmatically with the Create a SIP Credential REST API. You choose its username and a password for registration.

For a full walkthrough of the security, codec, and cipher settings, see the SIP trunking guide.

Controlling outbound calls

A SIP Credential’s call handler controls how it places outbound calls:

• default — use the outbound policy from your SIP Profile settings, for centralized management across endpoints.
• passthrough — allow the endpoint to dial PSTN phone numbers.
• block-pstn — block the endpoint from dialing PSTN phone numbers.
• resource — dial a specified resource and execute its instructions, for custom outbound workflows.

Resource SIP Addresses

To run your logic on inbound SIP calls, give the resource that holds that logic its own SIP Address. Inbound SIP traffic sent to that address is handled by the resource. You can assign a SIP Address to resources such as:

• AI Agent — connect the caller to a SignalWire AI Agent.
• SWML Script — execute a SWML script.
• Subscriber — route the call to a subscriber.
• Call Flow — hand the call to a flow built in the Call Flow Builder.
• Video room — connect the caller straight into a SignalWire video room.

To add a SIP Address to a resource from your SignalWire Dashboard:

Inbound BYOC

To send traffic from your own carrier to SignalWire (inbound BYOC), assign a SIP Address to the resource that should handle the calls. See the Bring your own carrier guide for the full flow.