P2P File Transfer System using WebRTC

🚧 Work in Progress...

Ongoing improvements to enhance transfer speeds for larger files.

🔹 Supports both LAN & WAN

• LAN Speed > WAN Speed

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📌 Overview

This repository contains the code for a peer-to-peer (P2P) file transfer system that leverages WebRTC to enable file sharing over local and wide-area networks (LAN & WAN). The system allows users to establish direct peer-to-peer connections without relying on a central server, ensuring faster and secure file transfers.

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📂 Files & Components

• index.html
  Contains the HTML & CSS for the front-end user interface, allowing users to:

  • Initiate connections
  • Select files for transfer
  • Monitor transfer progress

• index.js
  Implements the signaling server using Express.js & Socket.io, handling:

  • WebSocket communication between peers
  • Static file serving
  • Establishment of peer-to-peer connections

• package.json
  Defines the project's metadata and dependencies, including Express.js, Nodemon, and Socket.io.

• package-lock.json
  Ensures consistent dependency versions across different development environments by locking package versions.

• vercel.json
  Contains deployment configurations for Vercel, specifying source files and routing settings.

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🚀 How to Use

🔗 Live Demo: WAN_P2P

Or follow these steps to use the repository:

1. Open index.html on the devices that will participate in the file transfer.
2. On the first device, click "Create Local Offer" to generate a connection offer. Copy this text.
3. Share this offer with the second device (use Q-Text for easy sharing).
4. On the second device, paste the copied text into the "Remote" field and click "Connect". This generates a response in the "Local" section.
5. Copy this response and send it back to the first device. Paste it into the "Remote" field and press "Connect".
6. Once connected, the status will show "Connected to peer". The sender can now select a file and transfer it.

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⚙️ Mechanism

The P2P file transfer system operates in the following steps:

1. Signaling

   • Peers exchange session descriptions (offer & answer) through a signaling server (Socket.io).
   • This exchange helps establish a direct P2P connection.

2. Connection Establishment

   • WebRTC attempts to create a direct connection between peers.
   • Uses ICE (Interactive Connectivity Establishment), STUN, and TURN servers for NAT traversal.

3. Data Channel Creation

   • A WebRTC Data Channel is established for binary file transfer.

4. File Transfer

   • The sender transmits metadata (file name, size, type) first.
   • The file is read in chunks and sent via the data channel.
   • The receiver reconstructs the file upon receiving all chunks.

5. Transfer Monitoring

   • Both sender and receiver track the progress using a progress bar.

6. Completion & Cleanup

   • Once the file transfer completes, the connection is closed, and cleanup operations are performed.

✅ Why WebRTC for File Transfer?

• No centralized server needed (except for signaling)
• Direct peer-to-peer connection ensures fast and secure transfers
• Real-time communication via WebRTC's Data Channel

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👥 Team

• Nishant Kumar
• Viswanadha Sai Nissankararao (@ME)

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📌 Notes

• The system is currently under development to optimize performance for large files.
• WebRTC works best in LAN environments, but performance in WAN scenarios depends on network conditions.
• If WebRTC fails due to NAT issues, a TURN server may be required for relaying data.