Research On P2P Computing Technology Based On Java

Peer-to-peer (P2P) network is an open network platform that has powerful computing ability, can provide with various services, can support various interactions, and can deal with heterogeneous and distributed resources. P2P not only leads network computing from a concentrated mode to a distributed mode, but also enables network application core to move from central servers to user terminals which are distributed on the edge of network, and has advantages such as the higher utilization of network resources, the elimination of bottleneck caused by central servers, etc. JXTA-with interoperability, platform-independence, ubiquitous and security, is an open network computing platform and used to solve P2P computation and supply P2P application with a powerful and clever staging for low layer communication. The first practical instance about JXTA is based on Java. Due to the platform-independence of Java programming language, Java based P2P is especially suited for peer computing. Indeed, Java based P2P makes it an easy work to develop and apply application system and to develop efficient and secure network application system on different platforms. As a result, P2P has great commercial and technological potentials.This thesis deals with the P2P computing techniques based on Java. First, the history and state-of-the-art of P2P computing technology are reviewed, and the principle, system structure and main features of P2P computing technology are exposed, and the capabilities between P2P and client/server are compared fully. Then, fundamental elements of JXTA, which is a network computing platform designed for P2P computing, are expounded (including the system structure, the core components and protocols, the relationship between Java and P2P, the relationship between Java and JXTA, and the advantages of P2P network based on Java). Next, P2P application and some technical problems of P2P (including technology standard, efficiency about resource searching and routing algorithm, manageability and copyright, application model, and security) are addressed, and some methods are presented for solving these problems. Finally, an instant message system of pure P2P based on Java and JXTA is implemented by software. In this system, users can communicate directly, share resources and co-operate without relying on a central server. So it can avoid the efficiency decline and the node fault that take place when the amount of net users rises suddenly and can be used in other application fields. The work of this thesis is closed by indicating further directions of research.