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Spectrum Voice lets a SIP application, PBX, or voice agent place and receive live calls through a Spectrum iMessage line.
This guide is about live calls. To send an audio recording inside a message, use the voice() content builder.

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What is supported

Configure your SIP application to use TCP. Spectrum Voice does not currently accept UDP, TLS, or sips: connections.

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Choose a setup path

Inbound and outbound calling are configured separately. Set up one or both, depending on what your application needs.

Outbound calls

Configure SIP credentials and place calls from your iMessage line.

Inbound calls

Register inbound routing in the dashboard and receive calls in your SIP application.

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Quick reference

For outbound calls, configure your SIP application with these values: You can find the project ID and project secret in your project settings in the Spectrum dashboard. For inbound calls, register the inbound route in the dashboard. The dashboard connects the iMessage line to your SIP application.

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Business profile registration

A business profile is not required to place an outbound call. You can start building and testing before it is registered. However, outbound calls from an unregistered business may be flagged. For production traffic, we recommend registering the business profile in the dashboard. Registration is free and usually takes 1–2 business days.
Business profile registration and inbound route registration are different:
  • A business profile is optional and relates to outbound calling.
  • An inbound route is required if you want to receive calls.

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Current integration model

Voice is documented as a provider because it is a communication platform, but it does not yet use a voice.config() SDK provider. Today, your application connects directly through SIP:
  • Use SIP over TCP for inbound and outbound calls.
  • Use the dashboard to manage the project, business profile, line, and inbound route.
  • Do not expect voice calls in app.messages or app.webhook().
Webhook delivery, SDK call control, TLS transport, and voice-only lines are on the roadmap. No release dates are promised yet.