Decentralized networks offer two main advantages: no single point of failure and no capacity limitation. The more nodes added, the more potential gain in accumulative computing power and contents that the network can bring to the users. The amount of these distributed resources, however, grows tremendously over time. As such, an important problem, yet challenging, is how to manage the resources efficiently and be able to find them quickly when necessary in a network that is highly dynamic with frequent node membership changes. Many works attempt to address this problem, but only partially. If built together, they could provide a good set of services useful for the users. Unfortunately, such a combination is hardly feasible as most of these techniques differ fundamentally in system architectural design. This project develops a unified system infrastructure, that is scalable, self-organizing, and facilitates a comprehensive set of fast, accurate, and efficient information retrieval services for the users of decentralized networks. This infrastructure contains five components: (1) communication, (2) indexing, (3) search, (4) ranking/aggregation, and (5) security. The expected outcome includes a software implementation of the infrastructure with built-in technologies for these components. The development results will be disseminated via the Web, seminars, publications, and industrial collaborations. The educational plan is designed to significantly advance students' knowledge, at both undergraduate and graduate levels, and prepare them well for future professional endeavors. The project is applicable to any large-scale distributed information-sharing network deployed in the scientific, commercial, and homeland-security fields, to name some.
