This is the source code of a full-scale simulation of the Internet based on the Border Gateway Protocol (BGP), built on SpatialOS (http://improbable.io/2016/03/24/what-we-found-when-we-simulated-the-backbone-of-the-entire-internet-on-spatialos)
To compile and run this simulation, you need Unity and the SpatialOS SDK. You can apply to get early access to SpatialOS at http://improbable.io/get-spatialos