A secure peer-to-peer messaging protocol that provides end-to-end encryption, decentralized communication, and privacy-focused features. This protocol enables direct communication between users without relying on centralized servers.

Features

• End-to-End Encryption - AES-256 encryption for message security
• Peer-to-Peer Architecture - Direct communication without central servers
• Message Authentication - Digital signatures for message integrity
• Forward Secrecy - Perfect forward secrecy with key rotation
• Offline Capability - Messages stored locally when offline
• Group Messaging - Secure group chat functionality
• File Sharing - Encrypted file transfer capabilities
• Anonymous Communication - Optional anonymity features

Security Architecture

Encryption Layers

• Transport Layer - TLS/SSL for connection security
• Application Layer - AES-256 for message encryption
• Key Management - RSA-2048 for key exchange
• Authentication - ECDSA for digital signatures

Privacy Features

• No Metadata Storage - Minimal metadata collection
• Ephemeral Messages - Self-destructing message options
• Anonymous Routing - Optional onion routing support
• Zero-Knowledge Proofs - Privacy-preserving authentication

Tech Stack

• Protocol: Custom P2P protocol over WebRTC
• Encryption: AES-256, RSA-2048, ECDSA
• Network: WebRTC for peer-to-peer connections
• Storage: Local encrypted storage
• Frontend: React with TypeScript
• Backend: Node.js for signaling server

Installation & Setup

1. Clone the repository:

   git clone https://github.com/1cbyc/encrypted-p2p-messaging.git
   cd encrypted-p2p-messaging
   

2. Install dependencies:

   npm install
   

3. Generate encryption keys:

   npm run generate-keys
   

4. Start the application:

   npm start
   

Protocol Specification

Message Format

{
  "header": {
    "version": "1.0",
    "timestamp": "2024-02-28T10:30:00Z",
    "messageId": "uuid-v4",
    "sender": "peer-id",
    "recipient": "peer-id"
  },
  "payload": {
    "type": "text|file|group",
    "content": "encrypted-content",
    "signature": "digital-signature"
  }
}

Key Exchange Protocol

1. Key Generation - Each peer generates RSA key pair
2. Public Key Exchange - Exchange public keys via signaling server
3. Session Key Generation - Generate AES session key
4. Session Key Exchange - Encrypt and exchange session key
5. Secure Communication - Use session key for message encryption

Usage Examples

Basic Messaging

import { P2PMessenger } from './p2p-messenger';

const messenger = new P2PMessenger({
  peerId: 'user-123',
  privateKey: privateKey,
  publicKey: publicKey
});

// Connect to peer
await messenger.connect('peer-456');

// Send encrypted message
await messenger.sendMessage('peer-456', 'Hello, world!');

// Listen for messages
messenger.onMessage((message) => {
  console.log('Received:', message.content);
});

Group Messaging

// Create group
const groupId = await messenger.createGroup(['peer-1', 'peer-2', 'peer-3']);

// Send group message
await messenger.sendGroupMessage(groupId, 'Hello everyone!');

// Listen for group messages
messenger.onGroupMessage((message) => {
  console.log('Group message:', message.content);
});

File Sharing

// Send encrypted file
const file = new File(['content'], 'document.txt');
await messenger.sendFile('peer-456', file);

// Listen for file transfers
messenger.onFile((file) => {
  console.log('Received file:', file.name);
  // Save file to local storage
});

Security Considerations

Key Management

• Key Generation - Cryptographically secure random key generation
• Key Storage - Encrypted local storage with hardware security
• Key Rotation - Regular key rotation for forward secrecy
• Key Backup - Secure backup and recovery mechanisms

Network Security

• Connection Encryption - TLS/SSL for all network connections
• Peer Verification - Certificate pinning for peer verification
• Man-in-the-Middle Protection - Protection against MITM attacks
• DDoS Protection - Rate limiting and connection validation

Performance Optimization

Message Delivery

• Reliable Delivery - Automatic retry with exponential backoff
• Message Ordering - Sequence numbers for message ordering
• Compression - Message compression for bandwidth efficiency
• Caching - Local message caching for offline access

Network Efficiency

• Connection Pooling - Reuse connections for multiple messages
• Message Batching - Batch multiple messages for efficiency
• Adaptive Quality - Adjust message quality based on connection
• Bandwidth Management - Intelligent bandwidth allocation

Project Impact

This protocol has been used for:

• Secure Communication - Private messaging applications
• IoT Devices - Secure device-to-device communication
• Decentralized Apps - DApp communication protocols
• Privacy Tools - Privacy-focused messaging solutions

Future Enhancements

• Quantum Resistance - Post-quantum cryptography support
• Blockchain Integration - Decentralized identity management
• Voice/Video - Encrypted voice and video calling
• Mobile Optimization - Native mobile app development
• Enterprise Features - Enterprise-grade security features