The lives of people all around the world, especially in industrialized nations, continue to be changed by the presence and growth of the Internet. Its in?uence is felt at scales ranging from private lifestyles to national economies, boosting thepaceatwhichmoderninformationandcommunicationtechnologiesin?uence personal choices along with business processes and scienti?c endeavors. In addition to its billions of HTML pages, the Web can now be seen as an open repository of computing resources. These resources provide access to computational services as well as data repositories, through a rapidly...