Connect a phone number

An agent reaches the phone network through a connection: a SIP link between your carrier and SLNG. You bring your own phone numbers. They come from a carrier such as Twilio, not from SLNG. Create an inbound connection, an outbound connection, or both. An agent can use one connection in each direction. Inbound: a caller dials a number you own. Your carrier hands the call across the inbound connection to the agent, and audio flows both ways from there. Outbound: the agent opens the outbound connection to your carrier, which rings the number. Audio flows both ways once the person answers.

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Pick a direction

Choose whether the agent needs to receive calls, place calls, or both: If callers dial you and the agent also calls people back, create both.

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Pick a setup mode

Within each direction, choose a setup mode:

• Twilio: provider-specific guidance and a checklist for the Twilio console.
• Manual: SIP settings that you enter yourself. Use this mode with another carrier, or with Twilio when you want to configure the trunk without the guided flow.

An outbound Twilio connection uses Elastic SIP Trunking termination. An inbound Twilio connection gives you a webhook URL to paste into the number’s voice settings in Twilio.

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Where connections live

Connections are org-wide, like BYOK keys. You create them once and attach them to as many agents as the direction allows: Create and edit connections in the dashboard. The public API does not support connection management. You can attach an existing connection from either the dashboard or the API through sip_inbound_trunk_id and sip_outbound_trunk_id on the agent.

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When a connection cannot be attached

The dashboard marks an unavailable connection with the reason. The sip-trunk-options API endpoint returns the same reason in unavailable_reason.