типо такого должно быть
https://github.com/asterisk/asterisk/blob/7c52e1404223ecdf7a5863a1d8511def1a9f4bc6/configs/samples/pjsip.conf.sample#L233
Ага, вот нашёл интересное.
;auth_type= ; Authentication mechanism.
; Must be one of:
; "digest" : The standard HTTP/SIP digest
; authentication. "password" and/or one or more
; "password_digest" parameters must also be specified.
; "google_oauth": Google OAuth authentication used by
; Google Voice.
; "userpass" : (deprecated). Automatically converted
; to "digest". Used to mean plain-text password but
; that is now determined automatically.
; "md5" : (deprecated) Automatically converted
; to "digest". Used to mean pre-hashed password but
; that is now determined automatically.
; (default: "digest")

