With the development of the Internet of Things and the demand for telemedicine, the smart healthcare system has attracted much attention in recent years. As a platform for medical data interaction, the smart healthcare system is demanded to ensure the privacy of both the receiver and the sender, as well as the security of data transmission. In this paper, we propose a privacy-preserving data transmission scheme where both secure ciphertext conversion and malicious users identification are supported. In particular, the protocol is introduced to guarantee the two-way privacy of communication parties. Meanwhile, we adopt proxy reencryption algorithm to support secure ciphertext conversion so as to ensure the confidentiality of data in many-to-many communication pattern. In addition, by taking advantage of the concept of blockchain technology, a novel protocol is proposed to prevent data from being tampered with and effectively identify malicious users. Theoretical and experimental analyses indicate that the proposed scheme is practical for smart healthcare with high security and efficiency.

中文翻译：

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智能医疗中基于不经意传输和区块链技术的隐私保护数据传输方案

随着物联网的发展和远程医疗的需求，智慧医疗系统近年来备受关注。作为医疗数据交互的平台，智慧医疗系统需要保证接收方和发送方的隐私，以及数据传输的安全性。在本文中，我们提出了一种同时支持安全密文转换和恶意用户识别的隐私保护数据传输方案。特别是，引入协议来保证通信双方的双向隐私。同时，我们采用代理重加密算法来支持安全的密文转换，以保证多对多通信模式下数据的机密性。此外，利用区块链技术的概念，提出了一种新颖的协议来防止数据被篡改并有效识别恶意用户。理论和实验分析表明，所提出的方案适用于具有高安全性和效率的智慧医疗。