| It is today that the technique in computer science changes quickly, the distributed system is widely used, and people have been depended on the Internet. Every country pays more attention to the application of the distributed computer cooperation in every industrial field. The automatic industry is the dominant part in all the industries. Nowadays, not only in our country, but also in the whole world, can none of a company in die making finish the task, which is to make the die of whole vehicle in a limited period. But a virtual company can make it come true on a CAE truss with distributed cooperation technique through the network. It can split the process of design the large quantities of high precision die designing on bodywork. Each group only designs the part, which it is good at in different place. On the whole, each part is designed by computer supported cooperation work so as to keep the same step in precision and progress, and then assembled to be a figuration by the virtual company to assist forming technique analysis. This article is based on the task, which is called "the theory and the method of the cooperation design of the die of bodywork forming technique based on the web". It begins with the network for distributed design and the distributed theory, gives a distributed design model for the CAD/CAM application, and testified it in a simple distributed testing environment. As to the network condition, it adopts the Internet. It makes use of the wide resource and reduces the expense of the development as well. The inner structure of most nodes can be unchanged and the original study can be going on. The leaf nodes adopts the B/S model, which enhances the security of the system itself, releases the special technique operators from learning a great deal of compute operating knowledge and reduces the requirement of the hardware devices. The whole system supplies a distributed application platform, in which a coordinator takes the role of the core, assisted by a middleware to decide, and partly executed by Agents. I take the simple distributed management thought; use the reference of the theory of management to emphasize the coordinator's management privilege, and the method of the decision analysis in operational research to analyze it. I also use define the state of a coordinator decision and invalidation and competition by formula and give the simple algorithmic description. A middleware is running above the hardware and the operating system to support the development of the application software and the system software. The middleware has the standard program interface and protocols and can realize the share and the operation of the data on different hardware and operating system platform.There are three communication schemes taken by message oriented middleware, which are the message passing, the message queue and the message publish/order. They can't realize the aim to find the only correct receiver and make a direct connection between the applier and the receiver, while the communication middleware can. It adopts the thought of updating and based on the ability judgment to decide whether the node that is good at it can do the task. If it can, the applier will be noticed,or else it will turn to the coordinator. The middleware will notify the applier the decision information coming from the coordinator. Therefore, it breaks down the absolute privilege of the coordinator in the system, reducing its tension, and being able to notify the applier with the unique destination address. In the existing distributed system models, few pays attention to the mobile nodes for a variety of reasons. With the development of the computer technique and the wireless network, the mobile devices will be the fresh force used in the research. So I bring forward the authentication middleware model and later extend its function by increasing the authentication of the task in the work. In the practice, I also find the function can be extended to the authentication of the nodes that have moved. Age...
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