The SID of the [Account](https://www.twilio.com/docs/iam/api/account) that will create the resource.

The unique address you reserve on Twilio to which you route your SIP traffic. Domain names can contain letters, digits, and "-" and must end with `sip.twilio.com`.

A descriptive string that you created to describe the resource. It can be up to 64 characters long.

The URL we should when the domain receives a call.

The HTTP method we should use to call `voice_url`. Can be: `GET` or `POST`.

The URL that we should call when an error occurs while retrieving or executing the TwiML from `voice_url`.

The HTTP method we should use to call `voice_fallback_url`. Can be: `GET` or `POST`.

The URL that we should call to pass status parameters (such as call ended) to your application.

The HTTP method we should use to call `voice_status_callback_url`. Can be: `GET` or `POST`.

Whether to allow SIP Endpoints to register with the domain to receive calls. Can be `true` or `false`. `true` allows SIP Endpoints to register with the domain to receive calls, `false` does not.

Whether emergency calling is enabled for the domain. If enabled, allows emergency calls on the domain from phone numbers with validated addresses.

Whether secure SIP is enabled for the domain. If enabled, TLS will be enforced and SRTP will be negotiated on all incoming calls to this sip domain.

The SID of the BYOC Trunk(Bring Your Own Carrier) resource that the Sip Domain will be associated with.

Whether an emergency caller sid is configured for the domain. If present, this phone number will be used as the callback for the emergency call.