The Analysis And Implementation Of The P2P System Based On JXTA

P2P is a kind of network architecture composed of lots of network points which are equals with each other in the role, among of which the difference between the server and the client in the aspect of role is eliminated by the point which is known as peer and through the message between which complete the disputation and the information sharing directly. The JXTA platform is the representative implementation of P2P system, all the basic functions of P2P can be found in the platform. The base of JXTA platform, that is query mechanism, is researched carefully. It is pointed out that the character of multiple levels, in this way the high performance of network can be kept. The method and procedure of all kinds of elements of P2P communicate with each other according to the P2P protocols are analyzed in detail, and the same procedure is contrasted with the popular P2P systems. The design scheme, using safety mechanism in the peer group of JXTA, is put forward. The total procedure of creating, finding, joining and exiting peer group is implemented.In order to construct an isomerous distributed system based upon JXTA, another technology of distributed system, that is Web Service, is introduced. The architecture and protocols are analyzed, and the similarities and differences with the P2P system are distinguished.Through the above analyzing, an isomerous distributed system using middlewares to finish the visit to each other between P2P and Web Service system is brought forward, and the safety and veracity of visit the service must be ensured. The blue print of middleware is to adding the function of visit Web Service to the basic function of peer. The middleware is called Web Service Proxy, it performs as the agency of the peer when it wants to visit the outside service, and provides the service accepting and disposal of request to the Web Service, and then it is responsible for discovering, calling service and returning result.On the basic of two isomerous systems visiting each other, in order to find the related service position, the UDDI is added to the middleware. In this way service can be found although simple information is given. In addition, several middleware can group as a peer group, when a common peer joins in the group service which can be provide to enlarge the scale of query and to ensure the safety of system.