Overview

Recently, there has been an explosion of applications using peer-to-peer (P2P) and Grid-computing technology. On the one hand, P2P has become ingrained in current grass-roots Internet culture through applications like Gnutella [6] and SETI@Home [3]. It has appeared in several popular magazines including the Red Herring and Wired, and frequently quoted as being crowned by Fortune as one of the four technologies that will shape the Internet's future. The popularity of P2P has spread through to academic and industrial circles, being propelled by media and widespread debate both in the courtroom and out. However, such enormous hype and controversy has led to the mistrust of such technology as a serious distributed systems platform for future computing, but in fact in reality, there is significant substance as we shall see.

In parallel, there has been an overwhelming interest in Grid computing, which is attempting to build the infrastructure to enable on-demand computing in a similar fashion to the way we access other utilities now, e.g., electricity. Further, the introduction of the Open Grid Services Architecture (OGSA) [21] has aligned this vision with the technological machine-to-machine capabilities of Web services (see Chapter 3). This convergence has gained a significant input from both commercial and non-commercial organizations ([27] and [28]) and has a firm grounding in standardized Web technologies, which could perhaps even lead to the kind of ubiquitous uptake necessary for such a infrastructure to be globally deployed.

Although the underlying philosophies of Grid computing and P2P are...