Group calling

hello everyone ,
i am trying to install 10 sip cameras for 2 way audio video calls
can anyone help me how to make a group call to 10 extensions at a

i have installed freepbx 1.7.1 now i need to get 2 pstn trunk to my freepbx i have a micronet SP 5052 2 port fxo gateway can any one help to to add this trunk for incoming and out going call setup