<scp>IoT</scp> Data Transmission Security Using Blockchain With a Trust‐Weighted Proof of Authority Consensus Mechanism in Healthcare

ABSTRACT Healthcare systems generate vast amounts of sensitive data, and ensuring its security and privacy remains a significant challenge. Various traditional solutions, including encryption techniques, access control mechanisms, and centralized cloud‐based systems, have been developed to address these issues. However, these approaches often face challenges such as single points of failure, limited scalability, and lack of decentralized trust management. Encryption schemes such as AES and RSA are computationally expensive and do not inherently address issues of data integrity or transparency. At the same time, centralized systems are prone to security breaches and third‐party vulnerabilities. This paper proposes a blockchain‐based solution with a trust‐weighted proof of authority (PoA) consensus mechanism to overcome these limitations and ensure secure data transmission in the Internet of Things (IoT)‐enabled healthcare systems. The Density‐based Spatial Clustering of Applications with Noise (DBSCAN) algorithm is employed for healthcare data classification, followed by Huffman encoding for data compression. Data are encrypted using a combination of the Substitution‐Caesar cipher and Updated Elliptical Curve Cryptography (UECC). A novel trust‐weighted PoA consensus mechanism is then used for block validation, enhancing the security of data transmission. The proposed solution achieves an accuracy of 99.38%, an F1 score of 98.2%, a precision of 98.5%, a recall of 98%, a throughput of 65 Mbps, a latency of 0.23 s, and a processing time of 17 s. The results demonstrate that the blockchain‐based solution effectively addresses the shortcomings of traditional methods, ensuring higher security, scalability, and trust in healthcare data management.