Performance analysis of structured peer-to-peer overlays for mobile networks

Distributed Hash Table (DHT) based Peer-to-Peer (P2P) overlays have been widely researched and deployed in many applications such as file sharing, IP telephony, content distribution and media streaming applications. However, their deployment has largely been restricted to fixed, wired networks. This is due to the fact that supporting P2P overlays on wireless networks such as the public mobile data network is more challenging due to constraints in terms of data transmissions on cellular networks, limited battery power of the handsets and increased levels of node churn. However, the proliferation of smartphones makes the use of P2P applications on mobile handsets very desirable.  In this paper, we have analysed and evaluated the performance and efficiency of five popular DHT based structured P2P overlays (Chord, Pastry, Kademlia, Broose and EpiChord) under conditions as commonly experienced in public mobile data networks. Our results show that the conditions in mobile networks, including a high churn rate and the relatively low bandwidth availability is best matched by Kademlia and EpiChord. These overlays exhibit a high lookup success ratio and low hop count while consuming a moderate amount of bandwidth. These characteristics make these two overlays suitable candidates for use in mobile networks

Publishing and Discovery of Mobile Web Services in Peer to Peer Networks

Abstract: It is now feasible to host Web Services on a mobile device due to the advances in cellular devices and mobile communication technologies. However, the reliability, usability and responsiveness of the Mobile Hosts depend on various factors including the characteristics of available network, computational resources, and better means of searching the services provided by them. P2P enhances the adoption of Mobile Host in commercial environments. Mobile Hosts in P2P can collaboratively share the resources of individual peers. P2P also enhances the service discovery of huge number of Web Services possible with Mobile Hosts. Advanced features like post filtering with weight of keywords and contextawareness can also be exploited to select the best possible mobile Web Service. This paper proposes the concept of Mobile Hosts in P2P networks and identifies the means of publishing and discovery of Web Services in mobile P2P networks

Элементы геоморфологии никеленосной коры выветривания гипербазитов

Due to the astonishing development in memory and processing capabilities of hand held devices such as smart phones, it is not a dream anymore to enable mobile devices not only as conventional web service requesters but even as providers. The willingness and enthusiasm of service providers place abundant services at the disposal. But this abundance makes the efficiency of service discovery a critical issue. Centralized registries have severe drawbacks in such a scenario due to the dynamic and spontaneous nature of mobile peers. In the quest for a more appropriate approach for mobile web service discovery, we observed P2P to share very similar characteristics with behaviors of peers in mobile network. Hence we tried to find alternate mobile web service discovery mechanisms by using the features of the P2P networks like JXTA modules. The scalability analysis of the approach proves that the discovery can scale to the needs of large cellular networks

A Mediation Framework for Mobile Web Service Provisioning

Web Services and mobile data services are the newest trends in information systems engineering in wired and wireless domains, respectively. Web Services have a broad range of service distributions while mobile phones have large and expanding user base. To address the confluence of Web Services and pervasive mobile devices and communication environments, a basic mobile Web Service provider was developed for smart phones. The performance of this Mobile Host was also analyzed in detail. Further analysis of the Mobile Host to provide proper QoS and to check Mobile Host's feasibility in the P2P networks, identified the necessity of a mediation framework. The paper describes the research conducted with the Mobile Host, identifies the tasks of the mediation framework and then discusses the feasible realization details of such a mobile Web Services mediation framework.Comment: Proceedings of 2006 Middleware for Web Services (MWS 2006) Workshop @ 10th International IEEE EDOC Conference "The Enterprise Computing Conference", October 16, 2006, pp. 14-17. IEEE Computer Societ