# Smart Grid Protection, Automation and Control: Challenges and Opportunities
## 6 Comprehensive Cybersecurity Framework for VPAC Systems in Electrical Substations  
Cybersecurity is important in VPAC systems deployed in electrical substations from various perspectives, including hardware, software, and management processes [73; 92; 93]. Standardization for the IACS security mainly includes IEC 62443 standard [94] and IEC 62351 [25]. These standards provide flexible update mechanisms, the capability to manage vulnerability, and Role-Based Access Control (RBAC) [95], which integrate with enterprise LDAP servers [96]. The challenges are very serious--from proprietary operating systems not up to date with state-of-the-art security features, to heterogeneous network technologies introducing vulnerabilities, to ensuring VM isolation for preventing breaches [97; 98]. Virtualized environments introduce other risks due to the existence of the hypervisor layer, which could be compromised by \"hyperjacking\" attacks [99; 100]. The mitigation of these challenges requires a mix of traditional cybersecurity best practices and adaptive ones specific to virtualized systems, based on standards such as the IEC 62443 [94; 101] and NERC CIP [102; 103; 26]. The strategies presented in Table 23 are crucial for ensuring that cybersecurity risks related to VPAC systems are at their minimal levels. \begin{table}
\begin{tabular}{p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt}} \hline \hline
**Method** & **Advantages** & **Disadvantages** & **Weaknesses** & **Strengths** & **Opportunities** & **Threats** \\ \hline N & Low initial cost. & No failure tolerance. & High probability of total service disruption. & Simplicity in implementation. & Ideal for non-critical systems. & High risk of significant downtime in case of failure. \\ \hline N + 1 & Improves resilience against single failures. & Limited protection against multiple failures. & Does not ensure multiple failures. & Increases availability. & Suitable for critical systems with tolerance for one failure. & Risk if failures are multiple for one failure. & Risk if failures are multiple for simultaneous. \\ \hline \multirow{2}{*}{2N} & \multirow{2}{*}{High availability.} & Expensive and complex to implement and maintain. & High duplication cost. & High resilience. & Reduces downtime risk significantly in critical applications. & Complexity in management and high operational costs. \\ \hline \multirow{2}{*}{2N + 1} & Maximum availability and resilience. & Very high cost and extreme complexity in design and maintenance. & Complex operation and high maintenance costs. & Protects against multiple failures. & Ideal for mission-critical environments. & Management complexity and high operational costs. \\ \hline \hline \end{tabular}
\end{table} 
Table 22: Comparison of redundancy methods. The implementation of these standards ensures the secure operation, resilience, and continuous availability of critical systems against evolving cyber threats. In [97], it incorporates all smart grid standards that describe cybersecurity issues and provide information on their contents. One of the most relevant specifications for these systems today is the IEC 62443 family of standards, which specifies cybersecurity standards, policies, and procedures for IACS (Figure 14). Cybersecurity in VPAC systems considers the big picture of security integration in hardware, software, and networks. Table 25 summarizes key cybersecurity specifications for VPAC systems and their respective implementation strate