This project implements a Go-Back-N protocol for a chat scenario on the command line. It consists of two binaries: a client and a server. The client and server communicate with each other, allowing two participants to chat with each other. The implementation ensures reliable transfer of messages even in the presence of a bad network that can reorder, drop, delay, or duplicate packets. The communication is done using UDP packets with a payload size limit of 16 bytes.

• Chat between two participants: The client and server binaries facilitate a chat session between two users on the command line.

• Reliability using Go-Back-N protocol: The implementation employs the Go-Back-N protocol to ensure reliable transfer of messages over an unreliable network.

• Support for packet reordering, dropping, and duplication: The protocol handles various network conditions such as packet reordering, dropping, and duplication.

• Timer mechanism: Each sent packet has a timer associated with it, allowing the detection of lost packets through timeouts.

• User-friendly termination: The chat session can be terminated gracefully by entering three consecutive newline characters (two empty lines) in the user input.

• Threading for concurrent sending and receiving: Threading is used to listen for incoming ACK packets and data packets concurrently on both the client and server endpoints.

To build and run this project, you'll need the following:

• C programming language compiler (e.g., gcc)
• Linux environment

1. Clone the repository:

git clone https://github.com/ramazantokay/Go-Back-N-Chat.git

2. Change into the project directory:

cd Go-Back-N-Chat

3. Build the binaries:

make all

4. Start the server:

./server <client_ip_address> <server_port_number>

5. Start the client:

./client <server_ip_address> <server_port_number>

6. Start chatting between the client and server.

7. Terminate the chat session by entering three consecutive newline characters (two empty lines) in the user input.

This project is based on the Go-Back-N protocol described in the textbook "Computer Networking: A Top-Down Approach" by James F. Kurose and Keith W. Ross.

Please note that this implementation may contain limitations, potential bugs, and dependencies on external libraries and tools. While efforts have been made to ensure correctness, there is no guarantee of flawless execution. Exercise caution, conduct thorough testing, and adapt the code to your requirements. Report issues on GitHub and contribute to improvements. Use responsibly, validate results, and the authors disclaim liability for any damages or issues arising from the use of this code.

This project is licensed under the MIT License - see the LICENSE file for details.