What i\'m trying to do is group 2 clients and make them communicate with eachother. So if 2 clients are connected they would only be able to communicate with eachother and i
What youre trying is a message broadcast or a message-repeater-client. broadcasting is implemented on network layer (using brodcast the local network broadcast adress).
And if you implementing it that way, you'll flood your network, when you have more than 2 clients. Best regards to your network admin. ;-)