Yes, it is. The first peer to visit a multiplayer URL hosts the Quake 3 server in their browser. Subsequent visitors to the same multiplayer URL send UDP traffi

Yes, it is. The first peer to visit a multiplayer URL hosts the Quake 3 server in their browser. Subsequent visitors to the same multiplayer URL send UDP traffic directly to that peer. The packets travel directly between peers, not bouncing off any third server (after connection establishment). If your clients are on the same LAN, your UDP traffic will be entirely local, not going to the Internet at all (assuming your browser's WebRTC implementation provides the right ICE candidates). It won't work completely offline unfortunately, as the server is required for the connection establishment step in WebRTC. A peer-to-peer protocol for connection establishment on offline LANs would be awesome, but understandably low priority for browsers. The feature set of WebRTC is basically "whatever Google Meet needs" and then maybe a couple other things if you're lucky.