# Augmented Reality and the Digital Twin: State-of-the-Art and Perspectives for Cybersecurity
## 4 Perspectives for Cybersecurity
### Security-Relevant Application Areas for DTs with AR  
The identified application areas (cf. Section 3.3.2) can be a starting point for security-related AR-DT approaches, as well. This section describes how security plays a role and how the AR-powered DT may add to the current body of knowledge in these application areas. However, the application of an AR-DT4 Sec approach are, by far, not limited to the following variations. **Manufacturing:** The industrial/manufacturing area is potentially the main application domain using the AR-based DT for cybersecurity. Rather than acknowledging confidentiality and integrity, the industry has been solely focusing on their systems' availability over the last few decades. Ever since industry-based attacks, such as Stuxnet [69], appeared, the manufacturing industry and operators of critical infrastructures have been becoming aware of their systems' security issues. Additionally, moving towards Industry 4.0, Industrial Control Systems (ICS) converge with information technology (IT). This further increases the attack surface of industrial environments [71]. While the DT's main application area is the industry [26], recent works have also discussed applying DTs for security in industrial environments [8]. Therefore, AR-supported DTs can benefit industrial security, as well. For instance, while a system's imminent failure due to attacks might not be visible to an operator's eye on site, adding additional information from the DT via an AR device might reveal previously invisible misoperations. Moreover, AR-DT-intertwined devices might display visual representations of the system's logs or network traffic between systems imposed on the physical devices, enabling visual and contextual intrusion detection right next to the physical systems and allows for direct intervention with them. Furthermore, instructions for prompt mitigation procedures might be given that can be carried out at an operational site even by personnel with low or missing security knowledge. Previously, we identified predictive maintenance as the primary usage of DT-AR combined solutions in general. In this context, security can benefit from the combined solutions, too: Predictive maintenance approaches might be adapted to foresee potential security incidents and threats and throw alerts whenever an indication for a future attack is detected. **Education and Training:** In terms of education, the concept of combining AR with DTs can be especially valuable for cybersecurity education. Using the AR technology together with DTs can provide hands-on and visual effects for security learning [51]. Generally, the combination can provide a highly effective virtual training environment for cybersecurity. Well-established training methods, such as cyber ranges, can be extended with AR enabling a more immersive and intuitive training experience. For these scenarios, a cyber range appliance could be part of the AR-DT architecture. This application area could prove especially valuable with respect to cybersecurity situational awareness training and campaigns as it helps to highlight security topics and issues directly within the participants' domain. Thus, it becomes clear how cybersecurity is also a concern for their domain and could improve their willingness to adopt a more security-aware behavior. For example, approaches, such as [PERSON] et al. 's, which already benefit greatly from the use of a DT, could be further extended with AR [72]. Moreover, AR, together with DT, can be used to develop security-aware DT workshops. To that, the PDCA-learning cycle for AR-DT solutions [51] might be adapted to fit cybersecurity training. Furthermore, education instructing about how AR might support security-operating DTs might also present a potential educational aspect. **Cities, Transportation, and Energy Sector:** In contrast to the manufacturing area, the potentials for cybersecurity in the energy sector and critical infrastructures, including those for smart cities, slightly vary.