Peer-to-peer (P2P) networks have become an important infrastructure during the last years. Using P2P networks for distributed information systems allows us to shift the focus from centrally organized to distributed information systems where all peers can provide and have access to information. In previous papers, we have described an RDF-based P2P infrastructure called Edutella which is a speci...

The current state-of-the-art in Knowledge Management solutions still focuses on one or a relatively small number of highly centralized knowledge repositories with ontologies as the conceptual backbone for knowledge brokering. As it turns out, this assumption is very restrictive, because, (i), it creates major bottlenecks and entails significant administrative overheads, especially when it comes...

Even though they were introduced only a few years ago, peer-to-peer (P2P) filesharing systems are now one of the most popular Internet applications and have become a major source of Internet traffic. Thus, it is extremely important that these systems be scalable. Unfortunately, the initial designs for P2P systems have significant scaling problems; for example, Napster has a centralized director...

Peer-to-peer (P2P) file sharing systems provide infrastructure for communities to share storage space (e.g., Napster, Gnutella [1], Kazza [2]). Unlike traditional distributed systems, P2P networks aim to aggregate large numbers of computers that join and leave the network frequently and might not have permanent network (IP) addresses. In a pure distributed P2P system such as Gnutella, peers com...

Recently user−oriented online sharing communities have seen explosive growth. Two characteristics of these communities set them apart from traditional online message−based communities such as online forums. First, users have no social ties before joining the community. Second, there is little or no “verbal” communication between users. This research investigates the structure and dynamics of on...

The success of a P2P file-sharing network highly depends on the scalability and versatility of its search mechanism. Two particularly desirable search features are scope (ability to find infrequent items) and support for partial-match queries (queries that contain typos or include a subset of keywords). While centralized-index architectures (such as Napster) can support both these features, exi...

In recent years, the emerging diffusion of peer-to-peer networks is going beyond the single-domain paradigm like, for instance, the mono-thematic file sharing one (e.g., Napster for music). Peers are more and more heterogeneous data sources which need to share data with commercial, educational, and/or collaboration purposes, just to mention a few. Moreover, in current information processing app...

The limitations of client-serverbased systems become evident in an Internet-scale distributed environment. Resources are concentrated on a small number of nodes, which must apply sophisticated load-balancing and fault-tolerance algorithms to provide continuous and reliable access. Additionally, network bandwidth must be increased steadily to handle requests to and from successful Internet serve...

The Internet’s advent as the dominant application, content, and service delivery pipe set off a dramatic evolution among computing paradigms. The evolution continued as applications and services gradually migrated from client-server to edge services, and has now arrived at peer-to-peer (P2P) computing frameworks that can accommodate vast numbers of users. To comprehend this evolution’s impact, ...

T he limitations of client-serverbased systems become evident in an Internet-scale distributed environment. Resources are concentrated on a small number of nodes, which must apply sophisticated load-balancing and fault-tolerance algorithms to provide continuous and reliable access. Additionally, network bandwidth must be increased steadily to handle requests to and from successful Internet serv...