SimulCaster is a network protocol for Cloud VR. Virtual and augmented reality could be a big part of the future economy, but with current technology it is difficult to offer a high quality and low latency immersive experience without access to expensive PC hardware. With its innovative approach to latency, the SimulCaster protocol allows large-scale, high-quality immersive experiences on cheap, lightweight headsets, streamed directly from the Cloud. With immersive content housed in the Cloud and streamed only when needed, access to the spatial internet becomes instantaneous, opening a new universe of possibilities for applications of immersive technology.