Virtual Organizations Matei Ripeanu University of British Columbia Munindar P. Singh North Carolina State University Sudharshan S. Vazhkudai Oak Ridge National Laboratory T oday’s organizations are no longer constrained by traditional time and place barriers. Instead, in- formation technology supports virtual organizations: lexible networks of in- dependent, globally distributed entities (individuals or institutions) that share knowledge and resources and work to- ward a common goal. Generally, the set of shared resources isn’t limited to com- puting power but includes elements as diverse as storage, network links, data sets, analysis tools, sensors, and scien- ti ic instruments. The sharing policies that govern the use of these resources are necessarily highly diverse, given that sharing must be lexible, secure, and controlled over time and place, while respecting users and purposes. The Landscape A number of research communi- ties — preeminently grid computing and business-management communi- ties — have embraced the challenge of exploring and creating the necessary infrastructure to support virtual or- ganizations. They’ve made signi icant progress over the past decade: the vir- tual organization concept has been successfully realized in a growing set of domains ranging from collabora- tive work in business and science, to aircraft engineering, to multiplayer games, to medical data management, to supply networks. The software infra- structure enabling these deployments has become increasingly sophisticated, reliable, and scalable, and the research community is now better positioned to capture real users’ requirements. At the same time, the attention has shifted and goals have become more ambi- tious: the early focus on providing a software toolkit to support the creation and operation of virtual organizations has moved to building a uniform in- frastructure that, in addition to stand- alone software components, includes services and resources (computational resources, intermediate data storage facilities, high-speed networks, and so on). A telling example of this shift is the massive set of computational re- sources connected by optical links that the TeraGrid (www.teragrid.org) de- ploys to support several virtual organi- zations in collaborative science. Guest Editors’ Introduction 10 Published by the IEEE Computer Society 1089-7801/08/$25.00 © 2008 IEEE IEEE INTERNET COMPUTING