In the past four decades, several technological breakthroughs have made it feasible to sell computing as a service rather than a product. Supercomputers and clustering technologies have made huge amounts of raw computing power available, while time-sharing operating systems have made computing resources a divisible utility. Personal computers have educated generations of home and office computing users, who now depend on such devices. Meanwhile, the Internet has become the world's largest data and computing-service delivery infrastructure, offering a new platform for net-work-centric computing.

Recently, application service providers have begun marketing the ASP model, which uses the Internet or other wide area networks to provide online application services on a rental basis—commercially delivering computing as a service. For the ASP model to become the computing industry's mainstream paradigm, ASPs must make significant breakthroughs in networking infra-structure, computing technologies, and rental-based cost models and financial services.

If it can overcome the challenges facing it, the ASP model will foster a new generation of distributed, component-based computing services.