For a long time Skype's P2P architecture worked great. It was the absolute best A/V calling experience, handily beating every other contemporary mainstream offe

For a long time Skype's P2P architecture worked great. It was the absolute best A/V calling experience, handily beating every other contemporary mainstream offer from MSN to Y!IM. It had issues such as getting crushed by patch Tuesday, and I assume it was likely not robust enough to adversaries, but one thing you can't say about Skype was that its P2P architecture didn't work. It absolutely did. I think even though there were many things that could've lead to the demise of Skype's P2P network, it was pretty undoubtedly the rise of mobile phones. Android or iOS, Skype was just dreadful; they were clearly ducktaping mobile support in. Sometimes you'd be sending messages and everything would appear to be working, little did you know the other person was responding but you weren't actually seeing anything. Push notifications? Sometimes you get them, but it was a crapshoot as to when you would get them. It probably was expensive to try to bridge their P2P network to mobile phones, and it definitely didn't work very well. I guess anyone can just say these things and it's really difficult to back them up since a large part of it is subjective (and aside from some reverse engineering efforts, I am not really intimately familiar with much of the details behind Skype and its transition off of P2P) but I think there is one thing that most people would definitely not disagree with: Skype was far more relevant and well-regarded when it was peer to peer. That's not to say that the move off had anything to do with its downfall, more just to say that if it was so awful, I think it would've been the other way around.