[sip-comm-dev] architecture is been used in the sip communicator

Dear all
             I am new to sip communicator i have downloaded its complete
code from the net now i would like to know which architecture is been used
in the sip communicator project .and which class/interface is been used to
interact with the mobicents server (in localhost) while registering using
sip protocol please me

Thanks
Regards
Arpit kukreti