Build a demo application (Chat System) for Clear Voice Telecommunication (CVT) using Java core and Socket programming

I need help in developing a demo application (Chat System) for Clear Voice Telecommunication (CVT) using Java core and Socket programming. Technology:- Java Remote Method Invocation (RMI) User Datagram Protocol (UDP) Transmission Control Protocol (TCP). Requirement:- No need fancy UI. Just for demo. There are 2 type of users needed (agent and customer). After a successful login process, the customer must be able to communicate via text or voice chat (without uneven delays, and minor packet loss) with the agent. ONE agent can interact with maximum TWO customers only. If third customer requests for conversation, a new agent must be available (logged in) for chat. Otherwise system will ask the customer to wait for available agent.