TFA talks about it a bit, but your biggest problem is multiplexing/demultiplexing, since that requires you to essentially create a MITM attack (i.e. read the da

TFA talks about it a bit, but your biggest problem is multiplexing/demultiplexing, since that requires you to essentially create a MITM attack (i.e. read the data at a 3rd point besides the sender/reciever), which kind of defeats the purpose of quantum computing. They mention a hub based system, but again, TFA talks about scaling which can be very hard to do when you're essentially relying on a single point of failure that has to scale with the entire network.