A Public-key Encryption with Multi-keyword Search Scheme for Cloud-based Smart Grids

The smart grid is viewed as the next generation power system due to its reliability, resiliency, sustainability and energy efficiency. The smart grid technology has aroused widespread attention in communities of academia and industry over the years. Rapid development of smart grid enables more data to be collected and power to be efficiently distributed in real-time. With the increasing of power data, conventional smart grid cannnot satisfy the growing storage and data management demand. Cloud computing exactly handles these issues and is integrated with smart grid perfectly for more efficient operation of system. However, cloud-based smart grid system is vulnerable for various security flaws. Data confidentiality is one indispensable method of protecting users' privacy. Public-key Encryption with Multi-keyword Search (PEMKS) realizes the cloud server search encrypted files with users' multi-keyword trapdoor without revealing any information of retrival contents. In this paper, we propose a PEMKS scheme and apply it to cloud-based smart grid. Moreover, the proposed scheme is proved to be SS-sCKA secure and meets security requirements. Performance analysis indicates that the proposed scheme has better time complexity and lower storage cost compared with two recent PEMKS schemes.