Sixth International Workshop on Agents and Peer-to-Peer Computing (AP2PC 2007)

Peer-to-peer (P2P) computing has attracted enormous media attention, initially spurred by the popularity of file sharing systems such as Napster, Gnutella, and Morpheus. More recently systems like BitTorrent and eDonkey have continued to sustain that attention. New techniques such as distributed hash-tables (DHTs), semantic routing, and Plaxton Meshes are being combined with traditional concepts such as Hypercubes, Trust Metrics and caching techniques to pool together the untapped computing resources at the "edges" of the internet. These new techniques and possibilities have generated a lot of interest in many industrial organizations, and has resulted in the creation of a P2P working group on standardization in this area. (http://www.irtf.org/charter?gtype=rg&group=p2prg).In P2P computing peers and services forego central coordination and dynamically organise themselves to support knowledge sharing and collaboration, in both cooperative and non-cooperative environments. The success of P2P systems strongly depends on a number of factors. Firstly, the ability to ensure equitable distribution of content and services. Economic and business models which rely on incentive mechanisms to supply contributions to the system are being developed, along with methods for controlling the "free riding" issue. Second, the ability to enforce provision of trusted services. Reputation based P2P trust management models are becoming a focus of the research community as a viable solution. The trust models must balance both constraints imposed by the environment (e.g. scalability) and the unique properties of trust as a social and psychological phenomenon. Recently, we are also witnessing a move of the P2P paradigm to embrace mobile computing in an attempt to achieve even higher ubiquitousness. The possibility of services related to physical location and the relation with agents in physical proximity could introduce new opportunities and also new technical challenges.Although researchers working on distributed computing, MultiAgent Systems, databases and networks have been using similar concepts for a long time, it is only fairly recently that papers motivated by the current P2P paradigm have started appearing in high quality conferences and workshops. Research in agent systems in particular appears to be most relevant because, since their inception, MultiAgent Systems have always been thought of as collections of peers.The MultiAgent paradigm can thus be superimposed on the P2P architecture, where agents embody the description of the task environments, the decision-support capabilities, the collective behavior, and the interaction protocols of each peer. The emphasis in this context on decentralization, user autonomy, dynamic growth and other advantages of P2P, also leads to significant potential problems. Most prominent among these problems are coordination: the ability of an agent to make decisions on its own actions in the context of activities of other agents, and scalability: the value of the P2P systems lies in how well they scale along several dimensions, including complexity, heterogeneity of peers, robustness, traffic redistribution, and so forth. It is important to scale up coordination strategies along multiple dimensions to enhance their tractability and viability, and thereby to widen potential application domains. These two problems are common to many large-scale applications. Without coordination, agents may be wasting their efforts, squander resources and fail to achieve their objectives in situations requiring collective effort.This workshop will bring together researchers working on agent systems and P2P computing with the intention of strengthening this connection. The increasing interest in this research area is evident in that the four previous editions of AP2PC has been among the most popular AAMAS workshops in terms of participation. Research in Agents and Peer to Peer is by its nature interdisciplinary and offers a challenges for several communities, such as distributed systems, networks and database systems. We believe that all of these communities have much to contribute in terms of moving this area forward.