Not sure how what you mean? It contacts their server and asks it to generate a new key for a product for the currently logged in user. What are you planing?
I was simply wondering, if Microsoft use a cleaverly coded webscript (.aspx) to generate key-codes. Planning, err, nothing, just asking.
The keys are generated on their servers. Would be a pretty big mistake to do it client side, since clients would then be able to get the algorithm, and be able to tell their servers, that the key is a valid key for activation ;-)