Range Query over Encrypted Metering Data for Financial Audit

Smart grid, envisioned as an indispensable power infrastructure, is featured by real-time and two-way communications. However, how to securely retrieve and audit the communicated metering data for validation testing is still challenging for smart grid. In this chapter, we introduce a novel privacy-preserving range query scheme over encrypted metering data, named PaRQ, to address the privacy issues in financial auditing for smart grid. The PaRQ allows a residential user to store metering data on a cloud server in an encrypted form. When financial auditing is needed, an authorized requester can send its range query tokens to the cloud server to retrieve the metering data. Specifically, the PaRQ constructs a hidden vector encryption (HVE) based range query predicate to encrypt the searchable attributes and session keys of the encrypted data. Meanwhile, the requester’s rang query can be transferred into two query tokens, which are used to find the matched query results.