# Analysis of Security Issues and Countermeasures for the Industrial Internet of Things
## 4 Security Countermeasures in IIoT systems
### Perception Layer  
This layer consists of a large number of sensors and actuators. These components can automatically sense (i.e., identify) things and collect parameters (i.e., information) from the physical environment. The scale in the number of devices in an IIoT system shows that these devices can be stationed at once or incrementally upon the context and practical requirements [63]. Some unique security requirements in this layer are related to devices' authentication (prove its identity), authorization (whether it is allowed to access a resource), and securing access control of these devices for authorized data acquisition. Returning to our list of devised security issues, among others, we observe that security issues 4 (i.e., attack on physical devices), 5 (i.e., impact on devices' performance), 12 (i.e., anonymity), and 13 (i.e., cross-domain jurisdictions) are major concerns in this layer. To protect the devices from security issue 4, a more practical approach should be taken; e.g., the devices should be checked and monitored frequently and enhance the protection in the server storage. Moreover, the hardware of the device should be checked and evaluated frequently, particularly those that are unattended for a long time. Finally, we note that the SCADA system can play an important role in IIoT applications [140]. To protect a SCADA system, some physical security measures (standards) must be taken. For this purpose the employed hardware components should meet the NIST (National Institute of Standards and Technology) and FIPS (Federal Information Processing Standards) standards [141]. We observe that trustworthy data sensing systems can be enforced to address security issues 4 and 5. Service requests are granted in such a trustworthy system based on specific trust values calculated by a trust management system. However, trust management is highly dependent on how the trust is collected. Trust can be collected in two ways, directly (i.e., direct interactions between the entities) and indirectly (i.e., based on recommendations) [142]. In Figure 7, we illustrated a simple trust management process. For instance, an identity-based trust management model, e.g., [143], can be employed. This model follows a key-based trust agreement at the beginning of communication within a network domain. The novelty of this approach is that it can determine malicious objects coming from an outside network and is then able to update the other nodes within the network reading this malicious node information (with a specific trust value). Therefore, it can improve the authentication and authorization security of a network by reducing abnormal communications between the trusted and malicious nodes. It ensures protection for unauthorized control over the devices. To address security issue 12, a mobility-aware policy-based security technique can be employed [144]. This uses Quantum Lifecycle Management (QLM), a messaging standard that provides generic and standardized application-level interfaces for the IoT to achieve secure two-way communication in a privacy-preserving manner. Furthermore, this security technique enables real-time control over devices, and thus an entity can control a device's movements and restrict the device's information (e.g., location and activities) to others. In addition, IP-based security management protocols that are usable to a distributed system can be used for achieving end-to-end encryption and integrity protection between edge devices [145]. To address security issue 13, there is a need for seamless integration between various service providers and service users within the IIoT system. Importantly, this is to ensure that when a device is collecting data from other devices that reside in cross-domain jurisdictions, the legal issues (including policy enforcements) should be taken into consideration for acquiring resources and their distributions [146]. However, it is difficult for an IIoT system to seamlessly integrate the vast number of members of devices and their services.