Online/Offline Attribute-Based Boolean Keyword Search For Internet Of Things

With the rapid development of Internet of Things (IoT) and cloud computing, a large amount of IoT data has been stored and shared in cloud servers. However, sensitive IoT data may be leaked by untrusted cloud servers, which is a key problem hindering the development of IoT-cloud systems. To solve this problem, searchable encryption has been presented, which enables IoT devices to encrypt the collected data before uploading them to the cloud and make retrievals over the encrypted data by keyword queries. In this paper, we will study attribute-based keyword search (ABKS), which relieves us from cumbersome key management and provides a fine-grained access control. However, since the existing ABKS schemes are all constructed by bilinear pairings, which incurs high computational costs, they are not suitable for resource-constrained IoT devices. In this article, we propose an online/offline attribute-based boolean keyword search scheme, which can significantly reduce the online computing costs of IoT devices. In addition, our scheme can support boolean keyword search for data users, which has more flexible keyword expressivity than the existing online/offline ABKS schemes. We simulate our scheme and the experimental results show that it is both efficient and practical for the real IoT-cloud systems.