# Secure Proxy Re-Encryption Protocol for FANETs Resistant to Chosen-Ciphertext Attacks
## 2 Related Works and Applications
### Related Works
Therefore, a proxy re-encryption process is required, where the STP (semi-trusted party) transmits the previously encrypted sensitive medical information to emergency medical institutions without decrypting it. The information is re-encrypted by the STP before transmission, delegating the decryption process to emergency institutions. Ref. [8] is known as the first method introduced for delegating decryption rights, which marked an improvement over the traditional decrypt-and-then-encrypt approaches. In [9], [PERSON] et al. suggested an application called atomic proxy re-encryption, where a semi-trusted proxy converts a ciphertext for [PERSON] into a ciphertext for [PERSON] without seeing the underlying plaintext. Ref. [10] proposed a distributed-based authentication mechanism for drones in a swarm compatible with 5G D2D ProSe standard [11] mechanisms. It relies on a delegation-based proxy signature authentication scheme, reducing drones' communication overhead to the core network. The authentication scheme is lightweight, efficient, and scalable, suitable for resource-constrained drone networks. Ref. [12] presented a privacy-preserving sharing scheme for drone videos in public safety scenarios, using proxy re-encryption. It allows secure access for third parties, like first responders, without compromising video content privacy. The original encryption key remains confidential, and the scheme minimizes overhead, making it feasible for live streaming. Ref. [13] suggested a proxy re-encryption (PRE) scheme for decentralized storage networks using permissionless blockchains. It allows data owners to delegate access rights without revealing content. The PRE scheme is efficient, scalable, and resistant to collusion attacks, providing secure data access control in decentralized storage networks. Ref. [14] covered improved proxy re-encryption schemes for secure distributed storage, including their design, implementation, and performance measurements. It also discussed the benefits of using proxy re-encryption for access control in a secure file system. The pairing-based schemes introduced significant advancements, including the protection of the delegator's master secret key from collusion between the proxy and delegate. We now address proxy re-encryption papers that are secure against CCAs (chosen-ciphertext attacks). Ref. [15] presented a new definition of security against chosen-ciphertext attacks for PRE schemes and proposed a scheme that satisfies the definition. The construction is efficient and based only on the decisional bilinear Diffie-Hellman assumption in the standard model. The main contribution of Ref. [16] was the first construction of a unidirectional proxy re-encryption scheme with chosen-ciphertext security in the standard model. The construction is efficient and requires a reasonable complexity assumption in bilinear map groups. Ref. [2] proposed a new scheme for more efficient unidirectional proxy re-encryption and analyzed its security in detail, demonstrating its robustness against various attacks. The scheme has potential applications in various real-world scenarios and can contribute to the advancement of cryptography and data protection. Ref. [17] proposed a new scheme for proxy re-encryption that is secure against chosen-ciphertext attacks and collusion attacks, and does not require pairings. The scheme is unidirectional and the first of its kind with CCA security and collusion resistance. Ref. [18] proposed a unidirectional proxy re-encryption and proved its chosen-ciphertext security in the adaptive corruption model without random oracles, addressing an important question in the field. Overall, the paper's contribution laid in advancing the state of the art in secure proxy re-encryption schemes.