Skype replaces P2P supernodes with Linux boxes hosted by Microsoft

Is this in response to the Skype IP Lookup tool that was released this past week? Or something completely unrelated?

Something not mentioned by Ars is that the difference in cost between datacenter bandwidth and broadband has changed significantly in the last 10 years. Datacenter resources are now so cheap that P2P has little advantage. (I think the rise of cyberlockers are another manifestation of this trend.)

Let me just make this very clear: you don't go from zero operating cost to multiple millions of hardware and colo space to do the very same thing, in a move so transparent that it needs security researchers to dig into your program to find out it has happened at all.

I guess Skype (by extension, Microsoft) is growing interested in what people are speaking about. To get hold of that data you need to route it through your own network, at significant processing and bandwidth cost.

I would assume being able to guarantee a certain level or "service quality" played a bigger role than finding out what people are talking about. They're probably going to integrate Skype at a much deeper level into WP8 and they need to make sure there are fewer breaking points, both technical and legal.

That's one option. Other options:

a) datacenter bandwidth is now much cheaper than it was 10 years ago, to the point that the cost saving from using p2p is not that significant anymore. (Skype did not have zero operating cost, and contrary to the article, they did operate their own supernodes - few tens to a few hundreds at least).

b) Microsoft is going to change the business model, e.g. no more free calls (or, no more free conference calls, or something like that), and if they are going to charge money, they need to guarantee a level of service - which they cannot with a P2P infrastructure.

c) The marginal cost for Microsoft (who already have data centers etc) is actually LOWER than running a p2p, with everything (including end user liability) is taken into account. Running 10,000 servers in existing data servers would cost ~$1M/month. May seem a lot to you, but it's a rounding error for microsoft (and certainly, at a $8.5B total cost, 4 years would make this ~$8.55B from Microsoft's side. Rounding error)

d) Microsoft is planning some kind of integration with their other properties (hotmail? live? office live?) for which hosting everything is essential.

I would guess (c) or (d), although the parent's guess is not without merit.