Critical State Based Filtering System with Code Security for SCADA Network Protocols

SCADA (supervisory control and data acquisition) is a type of industrial control system (ICS). It’s a centralized system that monitors and control industrial processes that exist in the physical world. They work in Master ? Slave basis. This system is widely used in Power plants, traffic light control, power plants, etc., As it is a centralized system storing lot of data, there is chance for the attackers to hack the information. In the existing system, a special filtering system is used which acts as a firewall for the SCADA network. System is prevented from hackers by analyzing the state of the system. It involves the prediction of finding whether the system is close to the critical state.The problem is that only attack by the hacker is prevented. Any problem in the software of PLC (Programmable Logic Controller) is not identified. There is no protection against unintentional errors or and other code level attacks. Some errors will show only warning, the user will ignore the warning and upload the malicious code into the server thus affecting the entire system. We focus on software vulnerabilities in ladder logic; a popular graphical language for programmable logic controllers. We show how intentional or unintentional errors in the ladder logic code can lead to integrity and availability violations. We propose methods to support secure Programmable logic controllers code development and to detect vulnerable applications.