Distributed Information System for Experimental Investigations and Educational Process Support

The present paper is devoted to the distributed information system for support of research and educational process with remote access to informational and technical resources within the Intranet/Internet networks. The authors created the software and hardware of remote access and control described herein. This system is characterized by the network integration of computer-based research equipment for the natural sciences. It provides multiple access to such resources in the networks functioning on the basis of Protocol Stack TCP/IP. The access to physical equipment is realized through the standard interface servers (C C, GPIB), the access server of the microcontrollers i80C196KC, and the communication server, which integrates the equipment servers into uniform information system (see its structure outline on fig. 1). The system is used for making research task solutions in optical spectrography, as well as for supporting educational process at the Department of Physics of Petrozavodsk State University. Figure 1. The outline of the distributed information system The equipment server has a generalized structure. Device interfaces differ from each other only in their methods libraries that realize the interaction between the equipment server and a certain device. The equipment server determines whether the requested function and the equipment address are admissible for this equipment, transmits the request and the address to the equipment and forwards the reply or the error code to the client program if any exceptional circumstances occur. The communication server functions are: providing multiuser mode support; resources distribution; the prevention of unauthorized access to the experimental equipment; system monitoring; and security control. One of the advantages of the presented system is that the software controlling the experiment is running not at a remote computer (like in most web-technologies) but on the client’s computer connected to the system through the global net. Such structure and organization of the interaction in a multiuser system substantially increases its reliability. Besides, the structure of the communication server provides simultaneous access of few users to the research complexes or its subsystems. All the advantages of the presented structure are especially distinct while using the distributed system for education purposes. First, the simplified procedure of the equipment server creation provides easy introduction of scientific research equipment in educational process. Second, since all applications are run on the user’s computer, the equipment server takes less resource, which allows to use the already connected to the equipment computer as a server without any additional requirements to its resources. Third, it is possible to organize for students not only laboratory practice tasks within limited algorithms, but also carrying out unique scientific research experiments. This work was supported by Russian Foundation of Basic Research (grant No. 02-07-97503), U.S. Civilian Research and Development Foundation for the Independent States of the Former Soviet Union (CRDF) (award No. PZ-013-02), and Ministry of Education of