1. Objective

Getting Started: Familiarize yourself with socket programming.Implement: Develop a simple chat application for message exchange among remote peers.

2. Getting Started

Socket Programming: Beej Socket Guide: http://beej.us/guide/bgnet

3. Implement

3.1 Programming environment You will write C/C++ or Java code that compiles in Linux (e.g., Ubuntu) or Windows system

NOTE: You should (1) use TCP Sockets in your peer connection implementation; (2) use the select() API ormulti-threads for handling multiple socket connections; (3) integrate bothclient-side and server side code into one program and run on each peer.

3.2 Running your program Your process (your program when it is running in memory) will take one command line parameters. The parameter indicates the port on which your process will listen for the incoming connections. For example, if your program is called chat, then you can run it like this: ./chat 4322, where 4322 is the listening port. Run your program on three computers and perform message exchange.

3.3 Functionality of your program

When launched, your process should work like a UNIX shell. It should accept incoming connections and at the same time provide a user interface that will offer the following command options: (Note that specific examples are used for clarity.)

1. help Display information about the available user interface options or command manual.

2. myip Display the IP address of this process.

Note:The IP should not be your Local address (127.0.0.1). It should be the actual IP of the computer.

3. myport Display the port on which this process is listening for incoming connections.

4. connect :

This command establishes a new TCP connection to the specified at the specified < port no>. The is the IP address of the computer. Any attempt

to connect to an invalid IP should be rejected and suitable error message should be displayed. Success or failure in connections between two peers should be indicated by both the peers using suitable messages. Self-connections and duplicate connections should be flagged with suitable error messages.

5. list

Display a numbered list of all the connections this process is part of. This numbered list will include connections initiated by this process and connections initiated by other processes. The output should display the IP address and the listening port of all the peers the process is connected to. E.g.,

id: IP address Port No.

1: 192.168.21.20 4545

2: 192.168.21.21 5454

3: 192.168.21.23 5000

4: 192.168.21.24 5000

6. terminate

This command will terminate the connection listed under the specified number when LIST is used to display all connections. E.g., terminate 2. In this example, the connection

with 192.168.21.21 should end. An error message is displayed if a valid connection does not exist as number 2. If a remote machine terminates one of your connections, you should also display a message.

7. send

(For example, send 3 Oh! This project is a piece of cake). This will send the message to the host on the connection that is designated by the number 3 when command list is used. The message to be sent can be up -to 100 characters long, including blank spaces. On successfully executing the command, the sender should display Message sent to on the screen. On receiving any message from the peer, the receiver should display the received message along with the sender information.

(Eg. If a process on 192.168.21.20 sends a message to a process on 192.168.21.21 then the output on 192.168.21.21 when receiving a message should display as shown: Message received from 192.168.21.20

Senders Port:

Message:

8. exit

Close all connections and terminate this process. The other peers should also update their connection list by removing the peer that exits.