## 5 Fuzzy Logic Approaches in Trust Management
### Effective Metrics and Comparative Analysis of Methods Based on These Metrics
#### 5.2.1 Comparative Analysis Based on Metrics
By establishing a relationship between trust and privacy based on users' privacy policies and using cryptographic tools for information protection, the mechanism aims to provide users with control over their privacy settings and to ensure the confidentiality of their data. * Dynamicity: By updating trust values based on interactions and considering changes in user relationships over time, the Trust2 Privacy mechanism demonstrates a level of dynamicity in managing trust and privacy in a mobile social context. Scalability, integrity, availability, dynamicity, and context awareness are the five key criteria addressed in this article [28]:
* Scalability: The TACIoT system is designed to be implemented on both constrained and nonconstrained IoT devices. The Trust Manager component can be deployed on devices with varying hardware capabilities, indicating the level of scalability of the system. * Integrity: By incorporating pieces of evidence and security-related mechanisms into trust calculations, the system enhances the integrity of access control decisions and the interactions between IoT devices. * Availability: The implementation and testing of TACIoT on real devices in a testbed environment demonstrates the feasibility of the system for practical use. * Dynamicity: The flexibility and adaptability of the access control mechanism in TACIoT, along with the customization options for fuzzy rules and weights, suggest a level of dynamicity in the system. IoT devices can dynamically adjust their access control decisions based on changes in trust values and environmental conditions. * Context Awareness: The trust model in TACIoT considers multiple dimensions such as reputation, quality of service, security aspects, and social relationships. By considering these contextual factors, the system demonstrates the degree of context awareness when evaluating the trust values for IoT devices. The study [49] included a number of crucial integrity, availability, dynamism, and context awareness requirements, including:  
* Integrity: The methodology aims to enhance the integrity of trust management in 6G networks by employing GAN-based autoencoders for trust decision making and incorporating synergetic detection schemes. The system can detect and respond to potential threats or integrity breaches, thereby ensuring the reliability of the trust evaluations. * Availability: By leveraging AI techniques and fuzzy logic for trust evaluation, this methodology aims to maintain the availability of network services and data delivery. * Dynamicity: The dynamic nature of 6G wireless networks is considered using GAN-based autoencoders that can adapt to evolving trust scenarios. The ability of the methodology to learn and analyze trust information in real time enhances its capability to address dynamic changes in network behavior and trustworthiness. * Context Awareness: The integration of fuzzy logic for trust evaluation and adversarial learning for decision making enables the methodology to be context-aware in assessing trust levels based on specific network contexts and behaviors. Context awareness enhances the accuracy and relevance of trust evaluations in diverse network environments. In evaluating trust, ref. [48] satisfied the following requirements: scalability, integrity, availability, privacy, dynamicity, and context awareness:
* Scalability: The proposed framework was designed to be scalable, allowing it to handle large-scale 5G networks with multiple domains and tenants. * Integrity: The framework includes a trust management module that monitors, evaluates, and updates the trust chain generated among different network entities, thereby ensuring the integrity of the network. * Availability: This framework includes an intra-domain module that monitors the domain network for potential threats or ongoing attacks, mitigating them if needed and if possible, and ensuring the availability of the network.