Like all P2P networks, Skype continues to function well as it grows in size. As more and more users join Skype, they bring with them the processing power, data storage, and networking power needed to accommodate them. This is very different from traditional Internet applications, which require more and more servers and bigger and bigger network data pipes as more users join. In the traditional model of Internet applications adding more users eventually creates the need for more infrastructure, whereas, for a P2P network application such as Skype, additional users bring with them their own solution to growth! Perhaps the most important consequence of Skype’s growing, but self-sustaining, P2P network is that Skype doesn’t have to invest in and maintain large data-processing facilities of its own. This means that Skype can provide its softphone and services at very low or no cost to its users. It also helps explain how Skype can afford to give away free phone calls without going out of business: the simple answer is that it costs Skype nothing to do so—you bring the PC, data storage, and network connection and Skype merely provides a piece of (free) software. That’s why Skype can boast that Skype-to-Skype calls will always be free!
