Please take time to read all the links and PDFs. As suggested before anyone ask questions.
NO (depending on your receiver) you do not need a CAM.
It can connect direct to the older Diablo Wireless.
Fausto can connect via Internet/WiFI as Server/Client.
It can connect to a CAM or some card slots using Season Interface.
And it can use Serial/RS232/SSSP connection methods and connect direct to some receivers directly.
empb