Research on Security and Privacy in Fog Computing focuses on protecting data, applications, and devices in decentralized fog environments, where computation and storage are distributed closer to the network edge. This area addresses challenges arising from heterogeneous devices, limited computational resources, mobility, and real-time processing requirements. Key research directions include designing lightweight encryption and authentication mechanisms suitable for resource-constrained fog nodes, secure data aggregation and transmission protocols, and access control frameworks tailored for multi-tenant fog environments. Other emerging topics involve intrusion detection and prevention systems for fog networks, privacy-preserving data analytics using techniques such as differential privacy and federated learning, and trust management among heterogeneous fog devices. Additionally, research on secure integration with cloud infrastructures, blockchain-enabled security for fog computing, resilience against DDoS and other cyberattacks, and adaptive security policies for dynamic and context-aware environments represents significant avenues for advancing reliable and privacy-aware fog computing systems.