Gossip Protocol-based P2P Messaging Application

OVERVIEW

This is a peer-to-peer messaging app where multiple nodes can connect to each other and exchange encrypted messages. Messages are synchronized across the network using a gossip protocol.

INSTALLATION

Install dependencies:

pip install -r requirements.txt

RUNNING LOCALLY

Start the first node on port 5001:

py app.py 5001

In another terminal, start the second node on port 5002:

py app.py 5002

Open http://localhost:5001 and http://localhost:5002 in separate browser windows

• On the 5001 interface, click "Sambungkan Peer" and enter 5002
• On the 5002 interface, click "Sambungkan Peer" and enter 5001

Select a peer from the sidebar and send messages

HOW IT WORKS

• Each node generates RSA public/private key pairs on startup
• When you connect to a peer, your public key is exchanged
• Messages are encrypted with the recipient's public key
• The gossip protocol automatically spreads messages across all connected peers
• Messages are stored locally in SQLite databases

STRUCTURE

app.py - Main Flask server with all routes and logic
requirements.txt - Python dependencies
docker-compose.yaml - Multi-node Docker setup
static/ - CSS and JavaScript files
templates/ - HTML template
instance/ - Created automatically for database files

NOTES

• Each node listens on its own port (5001, 5002, etc.)
• Data persists in node_PORT.db files
• The app runs in debug mode locally
• Messages sync every 2 seconds in the UI