OPC (OLE FOR PROCESS CONTROL) IS AN INDUSTRY STANDARD CREATED IN COLLABORATION OF A NUMBER OF WORLDWIDE LEADING AUTOMATION HARDWARE AND SOFTWARE MANUFACTURERS IN COOPERATION WITH MICROSOFT. THE STANDARD CREATES A COMMON INTERFACE FOR COMMUNICATION BETWEEN VARIOUS DEVICES CONTROLLING TECHNOLOGICAL PROCESSES. THE OBJECTIVE IS TO PREVENT THE GIVEN MONITORING OR CONTROL SOFTWARE FROM BEING DEPENDENT ON THE HARDWARE MANUFACTURER. OPC IS BASED ON THE OLE/COM/DCOM TECHNOLOGY OF MICROSOFT, INC.IT PROVIDES MECHANISMS TO COLLECT THE DATA FROM DATA SOURCES AND COMMUNICATE THE DATA TO ANY CLIENT APPLICATION INDEPENDENTLY ON THE HARDWARE MANUFACTURER. OPC HAS THREE MAIN COMPONENTS : OPC DATA ACCESS, OPC ALARM & EVENT AND OPC HISTORICAL DATA ACCESS AND EACH ONE HAS BOTH CLIENT AND SERVER COMPONENTS ACCORDING TO CLIENT/SERVER ARCHITECTURE. OPC IS WIDELY USED IN DEVELOPING SCADA SYSTEMS. THIS ARTICLE TRIES TO INTRODUCE THE OPC STANDARD AND ITS USAGE IN SCADA INDUSTRY.

NOWADAYS, SECURITY HAS BEEN CONSIDERED AS A HIGHEST PRIORITY FEATURE IN SCADA (SUPERVISORY CONTROL AND DATA ACQUISITION) SYSTEMS BESIDES EFFICIENCY, THROUGHPUT AND TIME-RESPONSE AND MAKES SUCH REAL-TIME SYSTEMS DIFFER FROM OTHER INFORMATION PROCESSING SYSTEMS AND BUSINESS APPLICATIONS. BECAUSE OF THE POTENTIAL RISKS INVOLVED WITH OPERATIONS AND DATA PROCESSING, CONCERN FOR THE SECURITY BREACHES, INFORMATION THEFT AND CYBER THREATS, SCADA SYSTEMS MUST PROVIDE A HIGH LEVEL OF SECURITY FOR ALL OF THEIR COMPUTER-BASED ACTIVITIES. THIS PAPER PRESENTS NEW STRATEGIES AND APPROACHES TO STRENGTHEN SCADA SYSTEMS SECURITY.

THE PAPER PROVIDES A BRIEF EXPLANATION OF THE AUTOMATION AND SCADA INDUSTRY ALONG WITH NETWORKING SCHEMES. PROTOCOLS AS A CRUCIAL PART OF THE SYSTEM ARE EXPLORED IN DEPTH. IN ADDITION, COMMONLY USED PROTOCOLS AND STANDARDS ARE MENTIONED CONCISELY. THE NEWEST INVENTION OF THE IEC STANDARDS COMMITTEE, KNOWN AS IEC 61850, IS ALSO INTRODUCED. IEC 61850 AND UCA HAVE PROMISING ADVANTAGES OVER OTHER PROTOCOLS AND WILL GREATLY CHANGE SCADA SYSTEMS TODAY. ALSO, A GENERAL GUIDELINE IS PROVIDED FOR PROTOCOLS, WHICH IS THEN USED TO CREATE A COMPARISON CHART FOR THEM.

THE DEFINITION OF SCADA IS ‘SUPERVISORY CONTROL AND DATA ACQUISITION’. THE MAJOR FUNCTION OF SCADA IS FOR ACQUIRING DATA FROM REMOTE DEVICES SUCH AS VALVES, PUMPS, TRANSMITTERS ETC. AND PROVIDING OVERALL CONTROL REMOTELY FROM A SCADA HOST SOFTWARE PLATFORM. THIS PROVIDES PROCESS CONTROL LOCALLY SO THAT THESE DEVICES TURN ON AND OFF AT THE RIGHT TIME, SUPPORTING YOUR CONTROL STRATEGY AND A REMOTE METHOD OF CAPTURING DATA AND EVENTS (ALARMS) FOR MONITORING THESE PROCESSES. SCADA HOST PLATFORMS ALSO PROVIDE FUNCTIONS FOR GRAPHICAL DISPLAYS, ALARMING, TRENDING AND HISTORICAL STORAGE OF DATA. THE RELATIONSHIP BETWEEN THE CUSTOMER AND THE FOCUS OF SCADA SYSTEMS BY DIFFERENT ENVIRONMENT SUCH AS RADIO LINKS AND SATELLITE COMMUNICATIONS, FIBER OPTIC COMMUNICATIONS NETWORKS LAN, PSTN PHONE LINES AND GSM AND GPRS. IN THIS PAPER WE INTRODUCE A NEW IDEA IN THE FIELD OF BETTER CONTROL AND A MORE SECURE CONNECTION TO THE CORE OF EACH OF THE BASES UNDER REVIEW. IN THE PROPOSED SYSTEM WE ALLOCATE SPECIFIED ADDRESS BETWEEN THE LINES OF COMMUNICATION AND DATA FROM EACH SECTION CONNECTED TO THE NETWORK (CLIENT) CODES. AT THE CORE IN THE EVENT OF NON-COMPLIANCE WITH THE DEFAULT CODE SYSTEM GENERATE ALARMS. SCADA SYSTEMS ARE USED TO CONTROL AND MONITOR CONTROL PROCESSES IN EACH OF THE CUSTOMERS USED THESE MODELS. THE ADVANTAGE OF THE PROPOSED METHOD IS PREVENTING AND MINIMIZE EAVESDROPPING AND SABOTAGE AND MANIPULATION OF THE DATA TO THE MAIN SERVER. THE SECURITY FACTOR IN THESE SYSTEMS DRAMATICALLY INCREASES.

SCADA NETWORKS HAVE IMPORTANT ROLE IN MODERN INDUSTRIES AND INFRASTRUCTURES. THUS, SECURE SCADA COMMUNICATION IS IMPORTANT FOR INDUSTRIES AND INFRASTRUCTURES.KEY MANAGEMENT SCHEME IS ESSENTIAL FOR SECURE SCADA COMMUNICATION. THIS PAPER PRESENTS AND EVALUATES NEW AND HIGH-PERFORMANCE KEY MANAGEMENT SCHEME BY USING CCS SCALAR MULTIPLICATION AND COMPACT SD MODULAR MULTIPLICATION FOR ENCRYPTION AND DECRYPTION. THE RESULTS DEMONSTRATE THAT THE PROPOSED CCS COMPACT SD KEY MANAGEMENT SCHEME PROVIDES AN IMPROVEMENT IN TERMS OF THE NUMBER OF REQUIRED MULTIPLICATION STEPS COMPARED TO OTHER KEY MANAGEMENT SCHEMES.

SCADA (SUPERVISORY CONTROL AND DATA ACQUISITION) IS A TECHNOLOGY THAT LET USERS TO COLLECT INFORMATION FROM DISTANT INSTALLATION AND SEND THE CONTROL INSTRUCTIONS. IN THIS KIND OF SYSTEM, USER GIVE ALL THE OBSERVED INSTRUMENTS INFORMATION LIKE GAS AND OIL INSTALLATION, PIPE LINES OR POWER STATIONS, OPENING AND CLOSING VALVES AND SWITCHES, SHOWING ALARM AND COLLECTING MEASURED INFORMATION IN A DISTRIBUTED CONTROL SYSTEM (DCS) ROOM ACCORDING TO THESE SITUATIONS IMPLEMENTED THE CONTROL INSTRUCTIONS. PRESSURE PHYSICAL QUANTITY IS ONE OF THE USEFUL QUANTITIES IN INDUSTRIAL PROCESSES ESPECIALLY IN OIL, GAS AND PETROCHEMICAL INDUSTRIES. IN THIS WORK, DESIGNING THE PRESSURE QUANTITY CONTROLLER HAS BEEN PROPOSED BASE ON THE FUZZY LOGIC AND USING SCADA INFORMATION. THE POINT OF THIS PURPOSE HAS BEEN PROPOSED USING THE GRAPHIC USER INTERFACE (GUI), A MODEL FOR MONITORING TANK OUTPUT PRESSURE VARIATIONS WITH THE SETPOINT SIGNAL CONDITIONS THAT MAKES USER ENABLE TO STUDY THE RESULTS OF CONTROL PURPOSE EXERTION ON THE SYSTEM BESIDES SETPOINT SIGNAL CONDITIONS VARIATION. SIMULATION RESULTS ON TANK PRESSURE DEMONSTRATE THE PROPER ACCURACY AND CONTROLLER SPEED IN TRACKING SETPOINT SIGNAL.