If I want to use some fixed sip phones in the same office, you can make outgoing calls without logging in. But another rule is that when all the phones in the office want to make an international call, they must confirm the identity of the user and enter the password to make the call correctly.

Hello Gary,

I don't believe that we have any documentation on configuring a PIN for international calls. Some carriers do not require / support that feature, but you will still want to check with your carrier if they can set up a PIN to be used for international calls.

You could create a site where only certain people are allowed to make international calls with an International Number Plan. You also may want to suggest a passcode feature to allow international dialing in the Product Ideas Lab.