# Secure Proxy Re-Encryption Protocol for FANETs Resistant to Chosen-Ciphertext Attacks
## 2 Related Works and Applications  
### Related Works  
The suggested scheme focuses on the proxy re-encryption protocol for medical information within FANET (flying ad hoc network) environments. Considering a scenario involving off-road accidents, real-time video recording by drones becomes essential, necessitating a security protocol for transmission in the FANET environment. FANETs are a system in which unmanned aerial vehicles (UAV) or drones exchange information by forming a network. It is primarily a collection of communication technologies that allows drones or unmanned aerial devices to work together and share information. In particular, FANETs can be used to implement autonomous flight systems. Drones or UAVs can communicate with each other to monitor and control the situation while performing a given mission. This allows them to be applied to a variety of missions and applications: exploration and surveillance, rescue operations in disaster situations, crop surveillance in agriculture, and building communications infrastructure. FANETs implement various technologies related to security and safety through efficient communication and cooperation, and this is an area where more research and development is expected as the use of unmanned aerial devices increases. Consequently, this section will explore existing drone security protocols and research on securing medical information during emergency situations as related works. Subsequently, a specific focus will be given to proxy re-encryption, particularly unidirectional proxy re-encryption. First, we looked at drone-security-related protocols. Ref. [3] introduced a key management and delegation system to enhance multi-drone control system security. It minimizes the storage of sensitive data like group keys and flight information, employing a \"saveless\" property. Future work aims to adapt the system for small IoT devices and determine an optimal key renewal period balancing low computation cost and high security. Ref. [4] focused on a group authentication-based solution for drone swarm security, ensuring rapid and secure verification of new drones. The novel authentication scheme is faster than 3 GPP Release 17, with credentials not transmitted to the core network. Group authentication by guard drones and new parties facilitates swarm integration with reduced complexity. Ref. [5] discussed a lightweight authentication and key agreement (AKA) scheme for the internet of drones, addressing security challenges and privacy issues in a cost-effectivemanner. The scheme ensures secure data transmission using a lightweight encryption algorithm and a secure key exchange protocol. Ref. [6] introduced an anonymous mutual and batch authentication scheme with location privacy for UAVs (unmanned aerial vehicles) in FANETs. It ensures mutual authentication, batch authentication, and location privacy using group and ring signature schemes. The proposed scheme has potential applications in various fields, including military surveillance, emergency management, and environmental monitoring. The following is a study on medical information transmission security protocols. Ref. [1] proposed a secure medical record access scheme for on-road emergencies using a patient's smartphone and a cloud server. It ensures user privacy through pseudonyms and password-based authentication, improving the efficiency of accessing medical records during emergencies. The scheme enables timely healthcare in life-threatening situations. However, because this paper dealt with on-road emergency situations, drones were not involved. Ref. [7] is a review paper to discuss the security protocols for medical information using UAVs. It aimed to analyze the applicability of UAVs to support emergency medical systems in the areas of delivery and emergency urgent care. Next, we address proxy re-encryption. In emergency situations, having access to the previous medical records of the injured patient is crucially necessary.