Freepbx sip trunk configuration

Hi all members!

I need some help relating sip trunk configuration. The problem is that my provider uses 3 way authentication method, so I have: «User Name» (my phone number 38XXXXXXXX), «Authorization user name» (XXXXXXCKFT) and «Password». In 3CX it’s all OK, it has a checkbox for 3 way authentication. How I should define these parameters in PEER and USER detail and register string? And should I add some extra parameters in PEER box? (for example fromuser,fromdomain,disallow=all,allow=alaw&ulaw&g729,nat,canreinvite
insecure, dtmfmode…)

Thank you.