## 3 Proposed Approach
### Control Layer (SCADA/SIS) Attacks and Countermeasures  
The control layer is a critical security tier responsible for the real-time operation and control of physical infrastructure in energy systems. This layer includes essential systems such as SCADA/SIS, both of which are crucial for monitoring and controlling key industrial infrastructure, such as power plants and distribution networks. SCADA systems handle remote control and data collection, while SIS ensures the protection and safe operation of critical equipment, maintaining stability and preventing hazardous situations.  
Figure 2: Attack vectors of the physical layer.  
According to Figure 3, the diagram illustrates the control layer, highlighting potential attack vectors and the corresponding response processes. This layer includes SCADA and SIS systems, which are essential for controlling and monitoring physical equipment. The diagram shows how malware can infiltrate the system, tamper with data, and potentially disrupt the entire system's stability.  
The control layer's multi-faceted defense, particularly in SCADA/SIS systems, is crucial given the vulnerabilities exposed by both external attacks and insider threats. Unlike traditional control mechanisms that focus mainly on external breaches, this approach integrates countermeasures for 'cyber persona', or insider threats, including detailed behavioral analysis to preemptively identify malicious actions. In addition, while simpler control layers often lack protocol encryption, here, the integration of protocol encryption and digital signatures enhances command verification and reduces the risk of command tampering. This integrated design mitigates risks that simpler, one-dimensional control strategies do not address, thereby ensuring system integrity even under advanced persistent threats.  
Structured insider profiling per [PERSON]'s model enhances defenses, helping detect unauthorized access attempts and unusual behavior early. These individuals may unintentionally or deliberately compromise system integrity. For example, phishing or spear-phishing attacks could trick operators into executing malicious commands, while insider threats may bypass standard security protocols to gain unauthorized access to critical systems. To address network vulnerabilities effectively, the following measures should be implemented. To address control vulnerabilities effectively, the following measures should be implemented.  
* Systems typically use industrial standard communication protocols such as IEC 60870-5-104 or DNP3, but these protocols themselves can be exploited. To prevent this, communication encryption should be implemented, and additional transport layer security protocols, such as TLS, should be applied to ensure the secure transmission of data.
* By using digital signatures, the integrity of SCADA system control commands can be verified each time they are sent and received. This allows the system to detect and block any tampering of commands by malware. This defensive strategy incorporates real-time IDS/IPS monitoring to detect anomalies, supported by integrity verification  
Figure 3: Attack vectors and response processes of the control layer.  
for all control layer data. Such a structured approach reinforces SCADA system resilience, enabling proactive defense against complex attacks such as Industroyer.
* It is essential to implement comprehensive training programs for SCADA/SIS system operators to raise awareness of phishing attempts, social engineering attacks, and other cyber threats that exploit human vulnerabilities.  
These systems should be enhanced to monitor for 'cyber personas', as described by [PERSON], which includes profiling insider threats based on behavior patterns, unauthorized access attempts, and social engineering susceptibility. This approach ensures that both technical and human vulnerabilities are comprehensively addressed.