JXTA Platform Research Articles

Reliable Content Distribution in P2P Networks Based on Peer Groups

Peer-to-Peer (P2P) networks are highly dynamic systems which are very popular for content distribution in the Internet. A single peer remains in the system for an unpredictable amount of time, and the rate in which peers enter and leave the system, i.e. the churn, is often high. A user that is obtaining content from a selected peer is frequently informed that particular peer is not available anymore, and is asked to select another peer, or will have another peer assigned, often without enough checks to confirm that the content provided by the new peer presents the same quality of the previous peer. In this work we present a strategy based on group communication for transparent and robust content access in P2P networks. Instead of accessing a single peer for obtaining the desired content, a user request is received and processed by a group of peers. This group of peers, called PCG (Peer Content Group) provides reliable content access in sense that even as members of the group crash or leave the system, users continue to receive the content if at least one group member remains fault-free. Each PCG member is capable of independently serving the request. A PCG is transparent to the user, as the group interface is identical to the interface provided by a single peer. A group member is elected to serve each request. A fault monitoring component allows the detection of member crashes. If the peer is serving request crashes, another group member is elected to continue providing the service. The PCG and a P2P file sharing applications were implemented in the JXTA platform. Evaluation results are presented showing the latency of group operations and system components.

SAS-P2P - Secure Archive System P2P-Based with JXTA

Previous works have studied the characteristics and peculiarities of P2P networks, especially with regard to aspects of information security. Most work deals in some way, sharing resources, and in particular the storage of files. This work complements previous studies and adds new definitions relating to such systems. We developed a secure P2P storage system (SAS-P2P) using the JXTA platform, which uses standard X.509 digital certificates and PKCS#12, issued and managed by an infrastructure of public keys, also based on P2P technology. The information is stored in XML files in specially prepared, which facilitates the handling and interoperability between applications.

A process-view approach for cross-organizational workflows management

Workflow management for cross-organizational business processes presents a significant challenge recently. The development and implementation of new methodologies and technologies are imperative to tackle this challenge. The process-view approach provides a promising way to facilitate cross-organizational workflows management, especially when it is combined with powerful workflow modeling methods. With the assumption that workflow modeling methods in cooperative organizations are interoperable, a process-view and timed colored Petri net (TCPN) combined approach is proposed to manage cross-organizational workflows, including the formal definition, the mapping from TCPN workflow models to process-view workflow models in which the aspects of control flow and data flow are considered together, and the collaborative execution mechanisms of cross-organizational workflow instances. A hybrid P2P based decentralized workflow management system (WMS) combined with the process-view approach is proposed and built, which is placed on the top of the open JXTA platform and provides a flexible and scalable architecture for cross-organizational workflows management. At last, the cross-organizational workflows management for the distributed development of a circular saw has been used as a test case for system validation.

A Web services and process-view combined approach for process management of collaborative product development

Collaborative Product Development (CPD) across enterprises has been recognized as an effective strategy to connect multi-enterprise wide project teams to develop more competitive products. Process management is vital to the successful implementation of CPD in a multi-enterprise environment. In this paper, a novel Web Services (WSs) and process-view combined approach has been developed to manage the dynamic and distributed process of CPD to enhance the workflow interoperability among heterogeneous Workflow Management Systems (WMSs) of enterprises. Meanwhile, a hybrid P2P based WMSs framework has been built to provide an open and scalable architecture to deploy inter-enterprises collaboration. A software prototype system has been implemented using the open JXTA platform, and the collaborative development of a motorcycle has been used as a test case to validate the proposed approach and the prototype system.

Simulation et optimisation d'un environnement de calcul distribué sur un réseau pair-à-pair

Peer-to-Peer architectures are more and more studied by distributed computing community. The complexity of these networks is increased and the acceleration of the distributed applications is not ensured. That's why it is necessary to predict the performances as soon as possible in design and development phases, to bypass bottlenecks and correct program blocks which slow down the execution time. In this context, we propose P2PPerf: a simulation tool whose objective is to predict performances and execution times of a distributed application before its finalization. P2PPerf has been tested on a distributed computing application (Eratosthenes' Sieve) using JNGI: a P2P distributed computing environnement based on the JXTA platform.

P2PPerf: a framework for simulating and optimizing peer‐to‐peer‐distributed computing applications

AbstractPeer‐to‐peer paradigm is more and more studied by the distributed computing community. Indeed, this type of architecture has interesting properties like the absence of centralized topology, fault tolerance or dynamic reorganization of the network. However, managing these networks is complex and the acceleration of the distributed applications is not ensured. That is why it is necessary to predict the performance as soon as possible in design and development phases, to bypass bottlenecks and to correct part of the applications that slow down the execution time. In this context, we propose P2PPerf: a simulation tool that aims at predicting performance and the execution time of a distributed application before its finalization. P2PPerf has been tested on JNGI: a P2P distributed computing application using the JXTA platform. Copyright © 2007 John Wiley & Sons, Ltd.

A Multilayer Peer-to-Peer Framework for Distributed Synchronous Collaboration

Although interest in Web-based multiuser interaction is growing, classical server-based multiuser systems are becoming saturated. Consequently, the peer-to-peer (P2P) paradigm is receiving significant attention as an alternative. The authors propose a multilayer P2P framework for developing distributed synchronous collaborative systems using asynchronous P2P platforms. They've used the framework to develop a shared Web browser using the Java programming language and the JXTA platform