What Is WebRTC?
WebRTC (Web Real-Time Communication) is the browser technology that powers video chat without plugins or downloads.
WebRTC (Web Real-Time Communication) is the open-source technology that makes browser-based video chat possible. It's the reason you can video call someone on platforms like Glimr without installing any software — your browser handles everything natively.
How WebRTC Works
WebRTC enables peer-to-peer communication directly between two browsers. Here's the simplified flow:
- Media capture — WebRTC accesses your camera and microphone through the browser's MediaDevices API
- Signaling — Before two peers can connect, they need to exchange connection information. This happens through a signaling server (not part of WebRTC itself — platforms like Glimr use Socket.io for this)
- ICE candidate gathering — Each browser discovers its possible connection paths using STUN and TURN servers, generating ICE candidates
- Connection establishment — Browsers exchange offers, answers, and ICE candidates to find the best direct path
- Direct peer-to-peer stream — Once connected, audio and video flow directly between the two browsers, bypassing the server entirely
The critical insight is that after the initial setup, the server is no longer involved in the media stream. Your video and audio travel directly to the other person's browser, which means lower latency and better privacy.
Why WebRTC Matters for Video Chat
Before WebRTC, real-time video in browsers required plugins like Flash, Java applets, or proprietary browser extensions. These were:
- Security risks (Flash was notoriously vulnerable)
- Compatibility nightmares (different plugins for different browsers)
- Barriers to entry (users had to install and update plugins)
WebRTC eliminated all of these problems. It's:
- Native to browsers — No downloads or plugins required. Chrome, Firefox, Safari, and Edge all support it
- Peer-to-peer — Video goes directly between users, reducing server load and improving privacy
- Low latency — Direct connections mean minimal delay
- Adaptive — Automatically adjusts video quality based on network conditions
- Encrypted — All WebRTC streams are encrypted by default using DTLS and SRTP
Key Components
STUN Servers
STUN (Session Traversal Utilities for NAT) servers help your browser discover its public IP address. Since most users are behind a router (NAT), STUN helps determine how to reach them from the outside internet.
TURN Servers
TURN (Traversal Using Relays around NAT) servers act as relay points when a direct peer-to-peer connection is impossible (which happens for about 10-20% of users behind strict firewalls or symmetric NATs).
ICE Framework
The ICE (Interactive Connectivity Establishment) framework orchestrates the process of finding the best connection path between two peers, trying direct connections first and falling back to relay servers if needed.
WebRTC in Random Video Chat
Platforms like Glimr use WebRTC as the backbone of their video chat experience. When you're matched with a stranger, the platform's signaling server coordinates the WebRTC handshake, and then steps aside as your video streams flow directly peer-to-peer.
This architecture means:
- The platform never sees your video — streams go directly between peers
- Low latency — no round-trip through a central server
- Scalable — the platform only handles signaling, not heavy media processing
Browser Support
WebRTC is supported in all major modern browsers:
- Google Chrome (since 2012)
- Mozilla Firefox (since 2013)
- Apple Safari (since 2017)
- Microsoft Edge (since Chromium-based version)
- Opera, Brave, and other Chromium-based browsers
This near-universal support is why modern random video chat works seamlessly across devices without any downloads.
Definition
Web Real-Time Communication — an open-source technology standard that enables real-time audio, video, and data sharing directly between web browsers without plugins.
Category: Technology