# HAE: A Hybrid Cryptographic Algorithm for Blockchain Medical Scenario Applications
###### Abstract
This protocol, grounded in elliptic curve cryptography (ECC) and physical unclonable function (PUF), not only satisfies stringent security criteria but also boosts minimal communication and computational overheads. [PERSON] et al. [10] developed a privacy-preserving blockchain model with ring signatures. This scheme establishes a data storage protocol based on elliptic curve ring signatures. Leveraging the inherent anonymity of ring signatures ensures robust data security and conceals user identity within blockchain applications. [PERSON] et al. [11] introduced a blockchain-centric confidentiality privacy protection scheme, CP-BDHCA, to mitigate user latency, excessive computation, and single-point-of-failure vulnerabilities inherent in healthcare cloud servers. Initially, the scheme employs elliptic curve cryptography (ECC) for digital signatures, establishing secure communication among various healthcare entities. Subsequently, it integrates both AES and RSA to shield cloud servers from malicious threats. Notably, this scheme outperforms conventional models in response time and offers robust defense against DoS and DDoS attacks. Traditional cryptographic algorithms, like AES, boost impressive time efficiency. Their rapid encryption and decryption capabilities render them ideal for real-time data processing. This is particularly pertinent in healthcare applications where immediate data access is paramount. However, AES, as a symmetric encryption algorithm, uses the same key for encryption and decryption, which makes the security of the key critical. If the key is compromised or corrupted, all medical data encrypted using that key may be exposed or become inaccessible. This necessitates a secure mechanism for key distribution and management, an increasingly complex task in expansive healthcare systems. On the other hand, the elliptic curve cryptography (ECC) algorithm offers enhanced security with reduced key sizes and computational overhead, making it apt for resource-limited settings such as healthcare environments. Nonetheless, ECC may encounter efficiency challenges when processing large volumes of data. The computational complexity associated with ECC can render the encryption and decryption processes relatively sluggish, posing a concern in situations necessitating real-time access to medical data. Furthermore, if the encryption and decryption of medical data are not sufficiently secure or efficient, there is a risk of exposing sensitive patient information to unauthorized entities. Such exposure could not only infringe upon patients' privacy rights but also subject healthcare organizations to legal liabilities and reputational harm. Consequently, selecting an encryption algorithm that strikes a balance between security and efficiency is crucial for safeguarding patient privacy and ensuring the integrity of medical data. To address the challenges of ensuring data security, facilitating rapid encryption, and simplifying key management complexities, this paper introduces a hybrid cryptographic algorithm that integrates the strengths of both AES and ECC. In this approach, AES swiftly encrypts the data, while ECC is employed to secure the AES key. We apply the hybrid cryptographic algorithm to data storage and sharing in blockchain healthcare scenarios and experimentally analyze its security, time efficiency, resource consumption, and advantages. The principal contributions of this paper are as follows:  
1. We introduce HAE, a hybrid cryptographic algorithm based on AES and ECC. This algorithm employs AES for data encryption and ECC for encrypting the AES key. This approach not only ensures data security and algorithmic efficiency but also addresses the challenges associated with managing AES keys. 2. We have developed a blockchain-based healthcare application framework. Within this structure, we have seamlessly integrated technologies such as a blockchain and IPFS. Furthermore, we utilize the HAE hybrid cryptographic algorithm for the encryption and decryption of medical data. 3.