I'm researching the solution on Kamilio like SIP forward message:

- At the moment, the customer has server IP PBX and their clients.

- Then, the client just point the SIP Porxy configure to Kamailio. After that, Kamailio will forward to IP PBX and send the event to another server.

- Everything will be not changed for customer site. 

I found the link do the similar thing but it still authenticate on Kamailio: http://kb.asipto.com/asterisk:realtime:kamailio-4.0.x-asterisk-11.3.0-astdb#kamailio_configuration

Do you have any advice ? 

Regrads,

Hai Bui
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