SCADA (supervisory control and data acquisition) system is an advanced control system used in industrial and service sectors such as oil and gas, water treatment, nuclear energy, and electrical power generation to control and monitor the manufacturing or servicing process and maintain the process within predetermined values in order to induce desirable outcomes.
The SCADA architecture employs several protocols, including Modbus/RTU, Modbus TCP/IP, DNP3 and IEC60870. This paper will concentrate on the most widely used protocol in SCADA systems, Modbus TCP/IP, due to its widespread use, simplicity, and robustness. SCADA systems are vulnerable to cyber-attacks because Modbus/TCP lacks security measures for access control, authentication, and confidentiality. The paper contains valuable contribution by introducing an authentication technique to check the validity of messages in which the authorized users only pass this check, thereby adding a security measure to the SCADA system in terms of cyber-attacks.