As a practical application of the Internet of Things (IoT) in the modern industry, industrial IoT (IIoT) enables industrial enterprises to accelerate the development. Nowadays, the cloud computing technology has been applied to data storage and processing in IIoTs, but how to protect data privacy in the cloud has become a challenge and technical issue. Recently, the certificate-based encryption with keyword search (CBEKS) was presented to handle the cloud ciphertext retrieval. By CBEKS, one can get back all desired ciphertexts from the cloud without decrypting the ciphertexts or leaking the search keywords. However, the existing CBEKS scheme uses the computationally expensive bilinear pairing, which is disgusted by the performance-limited IIoT smart devices. In this article, a pairing-free and privacy-preserving CBEKS scheme is developed. The experimental results show that it has an obvious advantage in the computation performance when compared with the pairing-based CBEKS scheme. In addition, our security proofs indicate that it is secure against keyword guessing attacks.

中文翻译：

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支持IIoT的基于免配对证书的可搜索加密支持隐私保护的关键字搜索功能

作为物联网（IoT）在现代工业中的实际应用，工业物联网（IIoT）使工业企业能够加速发展。如今，云计算技术已应用于IIoT中的数据存储和处理，但是如何保护云中的数据隐私已成为一个挑战和技术问题。最近，提出了一种基于证书的关键字搜索加密（CBEKS），以处理云密文检索。通过CBEKS，可以从云中检索所有所需的密文，而无需解密密文或泄漏搜索关键字。但是，现有的CBEKS方案使用了计算量大的双线性配对，这受到性能受限的IIoT智能设备的厌恶。在本文中，开发了一种无配对且保留隐私的CBEKS方案。实验结果表明，与基于配对的CBEKS方案相比，它在计算性能上具有明显的优势。此外，我们的安全证明表明它可以安全地防范关键字猜测攻击。