> If all computers were publicly reachable it would be trivial to send files peer-to-peer.
WebRTC exists today, and it's quite good. It's not a technology problem, it's a matter of practicality. Mobile devices being reachable over the network 24/7 is just not realistic (connectivity falls off, battery considerations, etc.). I don't want my phone to heat up and come to a crawl because the video I just shared is being downloaded by three friends over LTE while I ride the train.
WebRTC exists today, and it's quite good. It's not a technology problem, it's a matter of practicality. Mobile devices being reachable over the network 24/7 is just not realistic (connectivity falls off, battery considerations, etc.). I don't want my phone to heat up and come to a crawl because the video I just shared is being downloaded by three friends over LTE while I ride the train.