Thanks — I’m responding to your question about what the “username” is in a SIP URI when you have a SIP trunk that uses a username and password. • The username in the SIP URI is the authentication identifier for the SIP trunk account. It identifies the trunk or account to the SIP provider and is used for SIP digest authentication (together with the password). • It usually appears in URIs like:

<sip:username@sip.provid>er.com

— where

username

is the value the provider gave you and

<http://sip.provider.com|sip.provider.com>

is the provider’s domain or host. • The username does not have to be a phone number (some providers use alphanumeric IDs); it just needs to match the credential the provider expects. • The full credential pair (username + password) is supplied in your trunk configuration and used during REGISTER or session setup messages; the username is what appears in the SIP identity/From/Contact fields and routing URIs. If you’d like, tell me: • the provider string you were given (or a masked example), and • whether you want the username shown in the From URI or only used for authentication, and I’ll show the exact URI format you should use or an example configuration. Sources: sip | livekit/livekit_composite | DeepWiki