The Design Of P2P-Based CSCW Platform

P2p (peer to peer), sharing of computer resources and services by direct exchange between nodes. Compared with the traditional mode C/S, it has advantage in making use of the unused information resource, storage space and CPU time on the network, avoiding the bottleneck brought by the server to improve the robustness of system, reduce the cost of the server, enhancing of using efficiency of the network bandwidth, improving of the flexibility of system, improving the user's autonomy. With the modern network environment more complicated than ever before, information source, information transferring and information flow control are more weak coupling, traditional centralized collaboration system will be the history, the distributed information management and application running environment will replace it. This is also the P2P technology's direction. The target of this research is to design an open and extendable CSCW platform based on P2P, compared with collaboration platform based on C/S mode, which is more flexible to the change of the collaboration environment, offers the user higher autonomy, makes use of the nodes' resource more adequately to improve the efficiency of the whole system. And the platform has good flexibility and extendability.The thesis based on investigating and analyzing nowadays P2P platforms, adopts the open source project JXTA of the SUN Co. Co. JXTA create virtual network based on Internet and non-IP network. It provides a simple, tiny and flexible mechanism to implement P2P computing in any platform, any network, anywhere and anytime.Based on research of collaboration mode, the thesis raises the concept layered virtual work group mode, the discretionarily layered group aggregate which is formed by the nodes in P2P network to execute one task. Using this mode, we can describe many kinds of collaboration work.Consulted with the microkernel pattern architecture and component technology, the platform can be decomposed to the layers: the microkernel layer, which is used to manage the components of the system and the communication between them and users can extend the function of the platform to satisfy different domain application by appending or delete component through microkernel; the common service layer, which supply common collaboration service such as group management, communication and object persistency; domain application service layer, which supply service to some domain applications. The lightweight kernel and weak coupling components makes the system more flexible and extendable. The thesis designed and implemented the workflow domain application service, designed and executed the workflow instance medical consultation process of blood illness.The analysis of the execution results of the medical consultation process of blood illness shows that the platform realizes the designation objects. It has good flexibility to the change of the collaboration environment, offers high autonomy to the users, and has good extendability.