# Open Radio Access Networks For Smart IoT Systems: State of Art and Future Directions
## 4 Challenges and Future Research Directions
### Future Research Directions
#### 4.2.2 Security and Privacy in O-RAN  
Dealing with security and privacy issues in O-RAN will require ongoing strategies involving continuous monitoring, assessment, and adaptation to evolving threats and regulations by implementing various measures and best practices to protect the network, devices, and data.  
Starting from end-to-end encryption protocols, access control mechanisms, robust authentication and authorization strategies, network segmentation, intrusion detection, and prevention methods, based on Figure 4, it is clear that individual security and privacy enforcement strategies are ineffective for O-RAN and emerging IoT systems. There is a need for security and privacy by design principles, where security and privacy measures are integrated into the design and development of these systems right from the beginning. In this context, the emerging O-RAN-based IoT systems should integrate security and privacy-preserving features, mechanisms, and best practices throughout the system's entire lifecycle, from its conceptualization and design to its deployment and maintenance.  
For example, at the initial stage, the system's threat surface should be identified and modeled to identify the potential security threats and vulnerabilities the system may face to guide the implementation of appropriate security controls. This will catalyze the realization of secured end-to-end architecture in the future that is designed with robust authentication mechanisms, access control strategies, and data encryption protocols to protect sensitive data and prevent unauthorized access. Incorporating secure communication protocols shall ensure data transmitted between IoT devices and the O-RAN network is encrypted and protected from interception. Also, the system should implement continuous monitoring mechanisms to detect and respond to security incidents in real time.  
One example of the security and privacy by design principle is the zero-trust architecture (ZTA), where every player is considered an adversary unless verified to be proven otherwise. The approach necessitates the continuous authentication, authorization, and monitoring of every network stakeholder requesting or providing resources to enhance security and reduce the risk of data breaches by minimizing the attack surface and limiting lateral movement within the network [93]. According to some recent research works conducted by [94; 95], the ZTA concept has been applied to secure several facets of safety-critical infrastructures. This includes communication networks and O-RAN on the one hand [95; 96; 97] and the different IoT domains on the other [98; 99; 100; 99; 101]. However, as is obvious from Figure 4, there is a need to develop ZTA to preserve the security and privacy of O-RAN-based IoT systems. Likewise, the open capability of O-RAN interfaces and the heterogeneous nature of IoT provide opportunities for malicious actors [102].  
One of the leading security groups, namely, the O-RAN Alliance Security Work Group, is continuously investigating the security challenges and defining O-RAN security solutions [103]. Among the feasible directions for overcoming this is the zero trust architecture (ZTA), which is currently on course for its standardization by the security focus group of the O-RAN Alliance community. To summarize, a body of mechanisms concerning security resilient design, AI-empowered threat detection and recognition, response, and recovery, considering the performance requirements of IoT applications, should be systematically studied. To this end, developing the integrated modeling, analysis, simulation, emulation, and testbed-based evaluation study should be carried out. In this way, systematically understanding the foundational capability and limitation of threats and the ability of defense schemes in the context of O-RAN enable IoT systems should be investigated.