I want to restrict some sip phones so that they will not able to dial pstn.
I know there is “Authentication” app that i can use but, i don’t want the user to press the password first before they are making pstn call.
Said I have SIP phone with extension 4112 and 4242
I want to allow 4112 to dial 9xxxxx
but the 4242 is not allow. how to achive this?