Btw, I tried hello a couple of weeks ago and it felt like voice/video over the net 5 or 6 years ago, no proper echo cancelation, similar to the old video plugin in pidgin. Also, there is no text IM.
It's based on the WebRTC standard, so in general, yes it's peer-to-peer. However, in cases where the peer-to-peer connection cannot be established (e.g. a user behind symmetric NAT), then a third-party relay server is used (called a TURN server) which acts as the intermediary between the peers (sort of like a proxy).
Btw, I tried hello a couple of weeks ago and it felt like voice/video over the net 5 or 6 years ago, no proper echo cancelation, similar to the old video plugin in pidgin. Also, there is no text IM.