| With the prominent development of industrial automation and network communication technology, industrial corporations demand that SCADA (Supervisory Control and Data Acquisition) System choose the configuration software with high reliability, real-time, security and friendly interface, and use advanced network communication means in order to collect the real-time data of industrial field and to report to management layer. This paper compared the functions of prevail configuration software, analyzed the disadvantages of Ethernet card connected into internet, and the disadvantages of wireless broadcasting station, and then selected MCGS and GPRS.In the facet of communication in SCADA System, based on the hierarchy ideology, this paper improved the conventional TCP/IP protocols, designed the protocol stack for the frontier collecting station with physics layer, data link protocol, network layer and transmission layer. The paper also designed a new encrypting algorithm for GPRS communication. The above point is a new idea in this paper.Acording the data structure and process control in SCADA System, this paper chose PID algorithm as the cycle strategy. In the communication between frontier collecting stations and hardware devices, this paper, based on the OLE interface theory, designed a common device driver interface template, including a serials of attributes and functions, which implemented the general operation for serial ports and collecting cards.The server used heartbeat algorithm to backup the data between the leading computer and the assistant one to guarantee data integrality and security, and this point is another new idea in this paper. The information is released in the network by the browsing methods of static web, ISAPI dynamic page and ActiveX controls.At last, the SCADA system implemented the supervisory of a city's thermic network by MCGS configuration software and GPRS communication. The actual running shows that the SCADA system is steady, secure and economical.
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