# HAE: A Hybrid Cryptographic Algorithm for Blockchain Medical Scenario Applications
## 3 Hybrid Cipher Algorithm Based on AES and ECC  
Individual encryption algorithms often have limitations but combining them can achieve more satisfactory results in practical applications. For instance, [PERSON] et al. [26] introduced DRMchain, a novel blockchain-based digital rights management model. This model employs the AES algorithm for content encryption and the EDSA algorithm for digital signatures, offering a robust, secure, efficient, and tamper-proof solution for digital copyright protection. [PERSON] et al. [27] employed the ECC algorithm for encrypting and decrypting data within wireless sensor networks. For key exchange, they utilized a key negotiation algorithm based on both ECC and Diffie-Hellman, known as ECDH. Additionally, for the authentication of communicating nodes, he adopted a digital signature algorithm that integrates both ECC and DSA, termed ECDSA. [PERSON] et al. [28] presented a composite cryptographic approach that leverages AES and RSA. In this method, RSA encrypts the AES key, while AES encrypts the data stored within the blockchain. [PERSON] et al. [29] developed a terminal data access control strategy to tackle data privacy and security challenges in the agricultural internet of things. This strategy employs CP-ABE and DES algorithms for hybrid data encryption, substantially simplifying key management and facilitating efficient encrypted data sharing. [PERSON] et al. [30] utilized the secure hash algorithm, SHA-256, for watermarking and storing these in the blockchain. Once encrypted with AES, these watermarks are integrated into images, thereby augmenting the image content's security, \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Public Chain** & **Private Chain** & **Alliance Chain** \\ \hline Network Structure & fully decentralized & partially decentralized & multiple trusted centers \\ Joining Mechanism & random joining & internal node joining & specific group vetting \\ Consensus & high fault tolerance & low fault tolerance & joining \\ Mechanism & and low transaction & and high transaction & tolerance and \\  & efficiency & efficiency & transaction efficiency \\ \hline \hline \end{tabular}
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Table 2: Three kinds of blockchain comparisons. anonymity, and integrity. [PERSON] et al. [31] introduced the elliptic curve certificate-less aggregated cryptographic signature scheme (EC-ACS) to bolster the security of electronic health records (EHRs). This approach employs ECC to encrypt medical data. Concurrently, the certificate-less aggregated signature scheme (CAS) generates digital signatures. The integration of blockchain technology ensures the integrity and traceability of the EHR. [PERSON] et al. [32] presented a novel video integrity verification method (IVM) grounded in a blockchain framework to counter video tampering attacks. This method synergizes a hash function-based message authentication code with the elliptic curve cipher to ascertain the video's integrity. Within this system, video clips of a fixed size are hashed, chained in real-time, and sequentially archived, culminating in a trustworthy database. During verification, the method is reapplied to the video clips, and the resultant hash value is juxtaposed with the one stored in the blockchain. In the ever-evolving medical domain, swift data access and stringent data protection are paramount. Building upon prior research, this paper introduces a hybrid cryptographic algorithm, HAE (hybrid AES and ECC), which synergistically integrates the strengths of AES and ECC to address the inherent challenges posed by conventional cryptographic algorithms in medical data applications. AES, a symmetric cryptographic algorithm, is renowned for its exceptional time efficiency, making it indispensable for real-time data processing--a critical requirement in medical applications. However, the symmetric characteristic of AES, where encryption and decryption employ the same key, presents a significant challenge: the secure distribution and management of this key.