## 4 Drone Forensics and Security Solutions--Review
This protocol was validated through global experimental tests and showed reasonable latency tradeoffs and minimal impact on network performance. In 2019, [PERSON] et al. [127] introduced a hybrid SDN and MQTT communication system for battlefield UAV swarms that was designed to be flexible, adaptable, and intelligent in order to support dynamic swarm formations, flexible data transmission, and enhanced security with a QoS-based multi-path routing framework. Case studies validated its practical effectiveness, although a more detailed discussion of the challenges and limitations would strengthen these studies. Collectively, these papers make significant contributions to secure, efficient, and anonymous communication systems for UAVs. In 2022, [PERSON] et al. [128] focused on drone forensics and machine learning with the aim of sustaining the investigation process. They recognized the increasing adoption of drones to address various challenges and provide support and convenience in areas such as medical supply delivery, surveillance, weather data collection, and home delivery services. However, the authors also acknowledge that drones have been misused for criminal activities. Their research entails a survey of artificial intelligence techniques in the literature that are relevant for processing drone data and uncovering criminal activity. Additionally, they proposed a novel model that leveraged machine learning to classify drone data as part of a digital forensic investigation. The authors concluded that properly trained machine learning models hold promise for accurately assessing drone data obtained from crime scenes. Their work paves the way for academia and industry practitioners to adopt machine learning techniques for the effective use of drone data in forensic investigations, contributing to the advancement of drone forensics. In more recent years, the following key technologies have emerged in drone security:  
**Drone security module**: The work of [PERSON] [129] in 2023 and the earlier work of [PERSON] et al. [130] considered a drone security module that can encrypt control signals and telemetry data between the UAV and the ground control station (GCS). These encryption mechanisms employed advanced cryptographic algorithms to secure data in transit, protecting against eavesdropping and unauthorized access. Their modules ensured the confidentiality (C) and integrity (I) of the communications, targeting UAVs (Z1), communication systems (Z2), and control hubs (Z3). However, their modules did not specifically address the availability (A) of the system, leaving it susceptible to denial-of-service (DoS) attacks. A further review of drone security modules was discussed by [PERSON] et al. [131]. **Blockchain for secure data storage**: The work of [PERSON] et al. [132], [PERSON] et al. [133], [PERSON] et al. [134], and [PERSON] et al. [135] considered blockchain technology to secure data transmitted to and from drones. By creating an immutable ledger of all interactions, the blockchain ensured that data integrity was maintained, preventing tampering or unauthorized modifications. These solutions targeted all security zones, including UAVs (Z1), communication systems (Z2), control hubs (Z3), command centers (Z4), and regulatory bodies (Z5). It provided comprehensive security coverage across confidentiality (C), integrity (I), and availability (A), although the potential for signal hijacking remained a concern. **Drone-assisted public safety networks**: The work of [PERSON] et al. [136] and [PERSON] et al. [137] proposed that UAVs augment public safety networks by being deployed to strategic positions. Their approaches utilized real-time data transmission and processing to enhance situational awareness and response times. The primary security targets were UAVs (Z1), communication systems (Z2), control hubs (Z3), and command centers (Z4). Their solutions enhanced integrity (I) and availability (A) by ensuring reliable data transmission and operational continuity in public safety operations.