client/server chat

I am a novice java script programmer, in need of a client/server chat application that i can put onto a web site.. The chat session MUST be a requested session between a client and the server. The session must be 1 to 1, but if another client joins they will be able to chat ONLY to the SERVER, they will not be able to see any clients online or any messages posted by other clients. But if possible, the code should cater for the multicast session, but be to alter the code to enable and disable it. ## Deliverables Complete source code of all programming work done