UDP Client-Server Communication Models (CN Lab)

This project showcases two implementations of a UDP-based Client-Server model in Python. Developed as part of our Computer Networks Lab at IIT Palakkad, it explores:

• Thread-based architecture: Concurrent handling of clients using threading
• Asyncio-based architecture: Event-driven concurrency using asyncio without manual threading

Originally developed in collaboration with @PranavRao25

Project Structure

Networks-Client-Server-Model/
├── thread-based/          # Uses socket + threading
│   ├── server.py          # Threaded UDP server with session management
│   └── client.py          # Simple command-driven client
│
├── no-thread-based/       # Uses asyncio for concurrency
│   ├── server.py          # Async UDP server with protocol state handling
│   └── client.py          # Interactive and file-based client with ALIVE/GOODBYE flow

How to Run

Thread-Based Version

cd thread-based

# Terminal 1
python3 server.py <port_number>

# Terminal 2
python3 client.py <server_ip> <port_number>

No-Thread (Asyncio) Version

cd no-thread-based

# Terminal 1
python3 server.py <port_number>

# Terminal 2
python3 client.py <server_ip> <port_number>

Features Implemented

✅ Custom binary protocol with headers
✅ HELLO, DATA, ALIVE, and GOODBYE message types
✅ Session ID, logical clock, and sequence number tracking
✅ Timeout handling for inactive clients
✅ Duplicate and out-of-order packet detection
✅ Clean shutdown using GOODBYE messages

Contributors

• Arnav Kadu
• Pranav Rao