Study And Design Of The Net Resource In LabScene-Distributed Instrument Development Environment

Since The nearest years, with the development of virtual instrument techniques and distributed object techniques, especially with the network communication technique making marked progress and the swift popularization of Internet, it causes that we may make a breakthrough at time and the limit of district and can connect the apparatus installation of distinct sites by means of the network for the purpose of cooperation. Also the distributed instrument system can make up of single virtual instruments such as the distributed system of measure and control, it can obtain stronger capability of computation, or achieve of the function that single instrument cannot finish. At the same time the development mode and realization technique of virtual instrument also changed from the traditional hardware to software gradually and the corporation of NI even extend this propose, "the software is the instrument ". At present for the sake of sufficiently utilizing the preponderance of Internet to achieve the apparatus to enjoyment and collaboration, more and more instrument start adopting the distributing type software control, and this causes network instrument and distributed instrument.The environment of developing distributed instrument (LabScene) is being coming into being below this backdrop, and it interests in supplying software technique about network, and strives to cause that the distributed instrument `s development can be easier and faster and more convenient. The environment of developing distributed instrument (LabScene) is one kind of distributed system that has both the software and hardware and it adopts numerous newly technique. For instance, in the respect of network, it is formed to the system to take the distributed technique. In the respect of integrated technique, LabScene is adopting the integrated technique based on the binary system code, groupware and unification interface. In the respect of operation, it is adopting graphical proxy flow, visual programming method. In the respect of management, LabScene used log file to log the every action of the system. And through entire item we adopt ageing model technique of UML, and draw the merit of the management mode of CMM.First of all my article introduces some conception correlating with the distributed instrument and the present situation of distributed instrument developing environment, and points out that the tendency of instrument and it's development has change from the hardware to software and now it changes to distributed software control. Secondly, in this article it is carefully depicted to the technique adopted in developing LabScene and the theory base, such as: the virtual instrument technique, distributed object technique, object oriented technique, distributed groupware. Especially, the multilayer layer distributed instrument is spreading the three layer network instrument and the research's importance is changed from sharing the net resources to study and resolve the coordinating of instruments. Third section is the emphases of this article, we describe those in detail, such as the architectural structure of LabScene, the mainly elements in LabScene, data flow between them and network resource part for model building, designing, interface and the essentials technique. And we also introduce some management and service of the server that against the network resource haves something to do with the server. Essentials in this section also are the main works of the article. It is introduced by following:Network topology: The data flow among the LabScene's main element has been analyzed in detail, and it is pointed out that the NR's network topology has extremely great preponderance in the application, and we analysis operation effectiveness of the system's data flow.The object organization: Utilizing the regions to manage objects in LabScene system and forming hiberarchy for the access control of net resources, LabScene supplies a relatively equilibrium settlement scheme in the interest of the net resource sharing and security throug...