Computer Networks

This repository contains a collection of 4 assignments completed as part of the CS425: Computer Networks course at IIT Kanpur under Prof. Adithya Vadapalli (Jan '25 – Apr '25). Each assignment focuses on a core networking concept, implemented from scratch using C++ and Python. They include a chat server, dns resolver, tcp handshake constructor and a routing simulator

---

📁 Contents

1. Chat Server (C++)

A multi-threaded TCP chat server featuring:

• User authentication
• Private and broadcast messaging
• Dynamic group creation and management
• Thread synchronization using mutex-guarded maps

2. DNS Resolver (Python)

Iterative and recursive DNS resolvers implemented using dnspython, with:

• Full traversal from root → TLD → authoritative
• Timeout and error handling for non-responsive servers

3. TCP Handshake (C++)

Custom TCP client using raw sockets:

• Manual construction of SYN, SYN-ACK, and ACK packets
• Header checksum and sequence number manipulation

4. Routing Simulator (C++)

Simulation of:

• Distance Vector algorithm (Bellman-Ford)
• Link State algorithm (Dijkstra)
• Arbitrary graph input and convergence analysis