Peer-to-peer communication

Hey there amazing people! This repository holds all the most authentic way, for transferring files (images, video, pdf, etc) over WebRTC datachannels.

Previous knowledge

From the last few months I have been working with WebRTC live streams & one-to-one chat's. But as soon as it comes to file transfer, the system used to crash.

Reasons for system crash:

• dataChhannel.BufferedAmount() get's full.

Solution:

• We need to implement a callback listener to listen when the dataChannel bufferedAmount decreases below 16Kib

if (dataChannel.bufferedAmount > dataChannel.bufferedAmountLowThreshold) {
    dataChannel.onbufferedamountlow = () => {
        dataChannel.onbufferedamountlow = null;
        send();
    };
    return;
}

Run Locally

Clone the project

  git clone https://link-to-project

Go to the project directory

  cd my-project

Install dependencies

  npm install

Start the server

  npm start 

The defauly port for the express server is 3000. Visit http://localhost:3000 to view it on browser.

Establishing Connection

To establish connection between two peer's whether on same network or on different networks, follow the steps mentioned below:

Suppose: 👨‍🎓 This is George & 🙋‍♀️ This is Anna. Let George intiate the connection with Anna, later they can transfer files to each other.

• George: Open http://localhost:3000 after executing npm start in his machine.
• Anna: Open http://localhost:3000 after executing npm start in her machine.
• George: Click on Create Local Offer and copy the text i'e automatically generated. Now pass this text to Anna via WhatsApp or Telegram (Note: WhatsApp/Telegram are behaving as our signaling server as of now.)
• Anna: Copy the text passed by george and past it inside Remote Offer text box, then click on Connect. Now you are gonna see some text automatically generated inside your Local Offer text box. Copy that & pass it to George.
• George: Copy the text passed by Anna and paste it under your Remote Offer text box, and click on Connect.

If the connecton above was successfull, the the status text above will change to Connected to peer.

Note: In future we will use WebSockets which will work as signalling server and we will get rid of all this text passing heck.

Sending files

File transfer with WebRTC can be bi-directional. To send files to your peer:

• Click on choose file button, choose the file you want to send, and boom the file has been sent to your peer.
• Transfer speed will depend on both of your bandwidths.
• If you are behind a NAT then transfer speeds can really decrease, becasue TURN servers used in this project are not the best.

Protocols

• SDP (Session Description Protocol)

Alternatives

• Building an SFU and transfer files over it.
• Check EasyFi Db for more information.

Authors

• 👔 @priyangsubanerjee

Features

• 🔑 No API key is required to upload a file.
• 💰 Uploads are completely free as of now.
• 📱 Send large files easily.