Special issue on information dissemination and new services in P2P systems

Information dissemination is an important P2P application that has received considerable research attention in recent years. P2P information dissemination systems range from simple file sharing applications to more complex systems that allows users to securely and efficiently publish, organize, index, search, update and retrieve data in a distributed storage medium. For complex P2P information dissemination systems, there is a need for features which include security, anonymity, fairness, scalability, resource management, and organization capabilities. For effective information dissemination, following features of P2P systems and infrastructure need to be updated: distributed object location and routing mechanisms, novel approaches to content replication, caching and migration, encryption, authentication, access control, and resource trading and management schemes. As P2P-based technologies play a more and more important role in the Internet, a number of new applications and services have been developed in the past few years, including file sharing, music downloading, live streaming, video on demand, and P2P based game platform. For these P2P systems, the key issues to be considered are scalability, robustness, reliability, and security. Moreover, today's networks are becoming increasingly more heterogeneous in terms of both network technologies and traffic, impacted by various factors including the wide deployment of wireless networks, diversification of multimedia formats, various requirements of different users, which brought many new challenges to P2P systems. The Call for Papers attracted nine submissions worldwide. After a rigorous review process, five papers have been selected for publication. An outline of the selected papers is presented as follows. The first article, by Jun-Hong Cui, et. al., attacks the problem of scalability, routing efficiency and complex query support for a P2P file sharing system. The authors propose a semantic overlay network of logical nodes, in which queries are routed on the basis of semantics. By exploiting the concepts of hierarchy and semantics, PSON has been demonstrated to support complex queries in a scalable and efficient way. The second article, by Zhipeng Ouyang, et. al., addresses a critical problem of factoring users’ subjective preferences in large-scale video streaming applications. The authors derive a model and formulate the problem as a resource demand vs supply problem. A framework is presented to address the challenge via efficient bandwidth allocation and group cooperation. The M. Song (*) Old Dominion University, Norfolk, VA, USA e-mail: [email protected]