This document summarizes a client-server chat application. It discusses networking basics like TCP, ports, and sockets. TCP ensures data is received in the same order sent using acknowledgements. Ports identify services/processes, and sockets connect two programs. The server runs each client on a separate thread. The client requests a connection to the server at a given port/IP. Classes like Swing, IO, and Net are used. Potential uses include private LAN chat, file transfer, broadcasting notices, and serving as a backup connection.

1. CLIENT-SERVER CHAT
APPLICATION
By
Piyush Rawat
PC Technology Pvt. Ltd.

2. Networking Basics
• Transmission Control Protocol (TCP)
• Port
• Socket

3. TCP
• This protocol ensures that the data sent over two points in a
Network is received in the same order as it is sent. This is
ensured by receiving acknowledgements from the receiver
side for every packet sent.

4. PORTS
• It is an address which determines the data origin and delivery
points over the Network. It is not a hardware device, but a
logical construct that identifies a service or process.

5. SOCKET
• A socket is one endpoint of a two-way communication link
between two programs running on the network. A socket is
bound to a port number so that the TCP layer can identify the
application that data is destined to be sent to.

6. Server Working
• The server is based on multithreading concept, which runs a
separate thread for each client connected to it.
• ServerSocket ss = new ServerSocket(3300); // a server socket is created
try {
while (true) {
new Handler(ss.accept()).start();
}
}
• The server is Broadcast type i.e. it allows the messages from
one client to be sent to other client and vice-versa.

7. Client Working
• The client requests connection to the server at a given port
and IP address.
• ip= getServerAddress(); //server address is received by user
s = new Socket(ip, 3300); //new socket is created at particular IP
and port
• Client is working on simple concept of creating new socket
and then sending and receiving messages
• Request of clients are placed in a cue for server to resolve.

8. Classes and packages used
• Server side:
• javax.swing
This package is dealing in providing user interface, i.e. panels,
scroll, text fields, etc.
• java.io
This package provides input/output facilities i.e. readers, writers, etc.
• java.net
This package provides network related facilities like creating server
sockets, accepting connections, etc.
• java.util
This package provides hashsets used for storing and updating objects
of DataOutputStream and name of different client connected to server.

9. Continued..
• Client side:
• javax.swing
Here also package is dealing in providing user interface, i.e. panels,
scroll, text fields, buttons, etc.
• java.io
This package provides input/output facilities i.e. readers, writers, etc.
• java.net
This package provides network related facilities like requesting server
for connections, sending and receiving messages, etc.
• java.util
This package provides hashsets used for storing and updating objects
of DataOutputStream and name of different client connected to server.

10. Final Implementation
Asking for IP address of server.

11. Asking for screen name

12. When user leaves

13. Scope
• Can be used for private chat over LAN and over Internet*.
• Can be further developed for file transfer.
• Can be used for broadcasting notices in an organization.
• Secure and reliable.
• Can also be used as a backup if there is sudden breakdown of
internet connection.
• Simple and effective with low memory and resource usage.
• No dedicated server is required if the application is used for
Local Area Network(LAN) i.e. any PC can become server.
• Basically this application can be for communication purpose
anywhere.
*For over the internet connection a dedicated server with global IP will be required.

14. QUESTIONS ?

15. Thank you