Kamilio as sip proxy

Asterisk Asterisk General
1

Hello.

I hope someone can tell me answer, because I spent a lot of hours finding answer on google, but no success.

I have this scenario.

Internet > asterisk pbx > VOIP provider

I was wondering if it’s possible to use kamilio for a additional security in registration SIP phones outside local network.

Internet > kamilio proxy > asterisk pbx > voip provider

I want that the user will have to register with two different passwords.
For example:

at sip.conf

            [218]
            type=friend
            context=company_internal
            username=218
            secret=112ddsaas
            nat=yes
            host=dynamic

AND with sip proxy with additional user name and password.

I need this because we already had once hack in our asterisk system.

Thanks for any additional information.