Control Network usage and connection

i need this small application for my office use. I wanted to control and see who is connected with my network and how much consumption they have done. here is what i want... i should be able to see how much internet usage has been done by individual PC. (upload/Download) (Connected over LAN and WIfi) (PC/Laptop/Phone) I should be able to block any wifi connection even if they have wifi password. as i wanted to block phone connection mainly .