Browser Fingerprints 101: WebRTC

What Is WebRTC

WebRTC, which stands for Web Real-Time Communication, allows for real-time communication between web browsers without the need for plugins or third-party applications. This technology has a wide range of applications, including:

• Video and Audio Calls: WebRTC is used to create in-browser video and audio call applications, making it valuable for remote work, online meetings, and telehealth services.

• File Sharing: You can use WebRTC to share files between web browsers without relying on email or other file transfer services.

• Real-Time Chat: WebRTC is employed in building real-time chat applications, enabling users to communicate through text, audio, and video.

• Online Collaboration: Many collaboration tools use WebRTC to facilitate real-time collaboration, such as screen sharing, whiteboard drawing, and collaborative editing.

• Online Gaming: Online games can implement WebRTC for multiplayer gaming and voice chat functionalities.

• Remote Desktop Access: WebRTC can be applied in remote desktop applications, allowing users to access and control other computers.

• Streaming: WebRTC supports real-time streaming, making it suitable for creating video streaming and streaming services.

Besides Facebook Messenger, WhatsApp, Discord, Google Meet, and Zoom, there are numerous other applications that utilize WebRTC technology. These applications include various communication platforms and services.

How does WebRTC leak IP

WebRTC technology enables web browsers to directly exchange audio and video streams without relying on intermediate media servers in most scenarios. However, in cases where NAT and firewall settings pose challenges, additional media servers may be utilized to obtain the actual IP addresses and establish communication between the parties involved.

What is NAT

When you connect to the internet, your device is typically assigned a local IP address, which is only valid within your local network. However, you may need to communicate with other computers on the internet, which requires mapping your local IP address to a globally unique public IP address. This mapping process is called Network Address Translation (NAT).

 

Imagine your home as a small village, where each person has their own house number (local IP address), but the entire village shares a postal code (public IP address). When you send a letter to someone outside the village, you need to include the postal code of the village so that the postal worker knows where to deliver the letter. NAT acts like a post office, responsible for routing your packets of data from the village (local network) to destinations outside (internet).

 

Therefore, NAT allows multiple devices to share a single public IP address and ensures that data packets from these devices are sent to the correct destinations. This way, multiple devices in your home can access the internet through a single public IP address, just like the entire village sharing a postal code.

In order to establish direct peer-to-peer connections for communication between web browsers, WebRTC needs to obtain the user's real IP address. WebRTC uses the ICE (Interactive Connectivity Establishment) framework to accomplish this, which consists of two main components: STUN (Session Traversal Utilities for NAT) and TURN (Traversal Using Relays around NAT).

• STUN Server：STUN servers are used to obtain the user's public IP address. By communicating with a STUN server, the browser can determine its public IP address and port. This is necessary because many users are behind NAT (Network Address Translation), which maps their internal IP addresses to public IP addresses. The STUN server helps the browser discover its public IP address.

• TURN Server：Sometimes, STUN servers may not be able to directly obtain the public IP address due to certain network configurations that may block it. In such cases, browsers can use TURN servers, which act as relays to help establish connections between browsers and bypass NAT. However, TURN servers often introduce additional latency in communication, so STUN is more commonly used due to its efficiency.

If the above principles are still unclear, it's okay. Just understand this: WebRTC uses STUN or TURN servers to obtain the user's real IP address for establishing peer-to-peer connections. This is part of WebRTC's real-time communication, but it has raised concerns about privacy and security, as your real IP address may be leaked.

How to check for WebRTC leaks

To check for WebRTC leaks, you can use a browser and access BrowserScan while connected to a VPN. In the IP address section, you can see the IP address obtained through the proxy and the real IP address (obtained by WebRTC).

Some VPNs or proxies may not solve the issue of WebRTC leaks, which can still pose privacy and security concerns.

How to Prevent WebRTC IP Leaks

There are several methods to prevent WebRTC IP leaks:

📌Disable WebRTC completely: In most modern browsers, you can disable or restrict WebRTC functionality through browser settings. You can usually find relevant options in the browser's settings or privacy preferences. Disabling WebRTC is one of the simplest methods.

📌Browser extensions: There are browser extensions specifically designed to protect user privacy and prevent WebRTC leaks. Examples include:  WebRTC Network Limiter, WebRTC Control, and WebRTC Leak Prevent. These extensions can help you have better control over WebRTC.

📌Choose a better proxy server or VPN: As mentioned earlier, some proxy servers or VPNs may not prevent WebRTC leaks. Therefore, when selecting such services, make sure to use BrowserScan to check for any WebRTC leaks.

📌Use anti-detect browser (recommended): Anti-detect browsers are excellent tools for privacy protection. Almost all anti-detect browsers in the market support modifying WebRTC functionality. This can prevent third-party websites from obtaining your real IP address. Even if they can obtain an IP address, it will be a proxy IP address, not your real IP address. Sometimes, replacing is more realistic than disabling, which makes websites perceive you as a regular user.

Read Also

Browser Fingerprinting Guide for Beginners

10 Browser Fingerprints to Know in 5 Minutes

IP Address

UserAgent

Canvas

Do Not Track(DNT)

WebGL

Geolocation

Language

Media Device& Audio

Client Rects & Fonts

Port Scanning

Bot Detection

Time Zone & Local Time & System Time

DNS Leak

WebGPU