Learn More
Scalability constitutes a key property in Peer-to-Peer environments. One way to foster this property is the introduction of super-peers, a concept which has gained widespread acceptance in recent years. We solve the problem of selecting super- peers in a distributed, scalable, self-organized way, supported by network coordinates. To this end, we present an(More)
Scalability constitutes a property of particular interest when investigating peer-to-peer overlay behavior. Recent advances that improve scalability include super-peer infrastructures and network coordinates. To this end, we introduce a lightweight simulation framework that focuses on peer-to-peer topology construction supported by network coordinates and(More)
Resource sharing in peer-to-peer environments with selfish participants suffers from the free-riding phenomenon unless the environment provides appropriate countermeasures. We present a concept for a distributed desktop grid which promotes fairness and inhibits free-riding. It contains a shared-history reputation mechanism designed for use in dynamic(More)
Network coordinates facilitate delay estimation in largescale networks. In particular, they support the creation of peer-to-peer-based desktop grid overlay structures. Landmark-based approaches to computing such coordinates have gained widespread acceptance in recent years. Several of these approaches produce coordinates by solving sequences of nonlinear(More)
Scalability constitutes a key property of Peer-to-Peer overlay networks. Recent advances that improve scalability include super-peer infrastructures and network coordinates. As an integral part of an upcoming middleware for distributed computing, we have developed a mechanism that builds and maintains a super-peer overlay network in a decentralized,(More)
Finding correlated words in large document collections is an important ingredient for text analytics. The naïve approach computes the correlations of each word against all other words and filters for highly correlated word pairs. Clearly, this quadratic method cannot be applied to real world scenarios with millions of documents and words. Our main(More)
Ring topologies are peer to peer network structures that organize the nodes in a ring. Each node knows its direct neighbors and a few other nodes but has no global view of the network. In such a network it is complicated to measure or estimate the number of participating nodes. We provide a lightweight, distributed algorithm to estimate the size of the node(More)
Chord has proved to be a robust and efficient self-organizing structured Peer-to-Peer overlay. In this paper, we show that with the addition of super-peers, bidirectional communications, and two novel routing improvements, Chord can safely operate in environments with firewall-protected peers at a considerably reduced end-to-end message delay. Our concept,(More)