This document summarizes a Java-based chat application created by DVS Technologies. It discusses what chatting and chat applications are, how they allow real-time communication, and how they are used on websites and mobile devices. It then explains the technical details of how sockets allow for two-way communication between client and server programs by binding to specific port numbers, allowing the server to listen for connection requests and the client to identify the server to connect to. Diagrams demonstrate how a port scanner can find the port a chat server is listening on so the client can connect and authenticate with the server.

1. Chat Application: a Java-based
chat application
Guided By Prepared By
Ms Nehal Pa5tel Parth
Patel
(12IT066)

2. What is Chatting?
• On the Internet, chatting is talking to other people
who are using the Internet at the same time you
are.
• In some cases, a private chat can be arranged
between two parties who meet initially in a group
chat.

3. What is Chat Application?
• Chat Application is primarily meant based group
chat to refer to direct one-on-one chat or text.
DVS Technologies provide both type of chat
application. DVS Technologies chat application
facilitates real-time communication, with its
superior feature set and unprecedented reliability.
DVS Technologies chat application increases the
efficiency of the communication process.

4. • Many of our clients are using DVS Technologies
chat application in their websites worldwide for
communicating to their prospective clients. We
can embed different type's forms to login to the
chat application.

5. How Mobile Chat application looks like

6. What Is a Socket?
• Definition: 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 [4].
• Normally, a server runs on a specific computer
and has a socket that is bound to a specific port
number. The server just waits, listening to the
socket for a client to make a connection request.

7. • On the client-side: The client knows the hostname of
the machine on which the server is running and the
port number on which the server is listening. To
make a connection request.The client also needs to
identify itself to the server so it binds to a local port
number that it will use during this connection. This is
usually assigned by the system.

8. • If everything goes well, the server accepts the
connection. Upon acceptance, the server gets a
new socket bound to the same local port and also
has its remote endpoint set to the address and port
of the client. It needs a new socket so that it can
continue to listen to the original socket for
connection requests while tending to the needs of
the connected client.

9. • On the client side, if the connection is accepted, a
socket is successfully created and the client can use
the socket to communicate with the server.
• The client and server can now communicate by
writing to or reading from their sockets.

10. Port Scanner
findTheApplicationPort(Host Address,
Start Port,
End Port )
Keep Trying…

11. Port Scanner
Chat “Client” Chat “Server”
(Port 50005)

12. Port Scanner
Chat “Client” Chat “Server”
(Port 50005)Try 50000…
Timeout …

13. Port Scanner
Chat “Client” Chat “Server”
(Port 50005)
PortScanner
Ooops!

14. Port Scanner
Chat “Client” Chat “Server”
(Port 50005)
PortScanner
Try 50001…
Try 50002…
Try 50003…
Try 50004…
PortScanner
Threads

15. Port Scanner
CheapChat
“Client”
CheapChat
“Server”
(Port 50005)PortScanner
PortScanner
Threads
Connect at
50005
Authenticate:
“Are you a
Chat server?”

16. Port Scanner
CheapChat
“Client”
CheapChat
“Server”
(Port 50005)PortScanner
PortScanner
Threads Reply:
“I am a Chat
server!”

17. Port Scanner
CheapChat
“Client”
CheapChat
“Server”
(Port 50005)
Connect at
50005

18. • This is how communication between server
And Client takes place using socket.

19. Thank You