As smart grids are getting popular and being widely implemented, preserving the privacy of consumers is becoming more substantial. Power generation and pricing in smart grids depends on the continuously gathered information from the consumers. However, having access to the data relevant to the electricity consumption of each individual consumer is in conflict with its privacy. One common approach for preserving privacy is to aggregate data of different consumers and to use their smart-meters for calculating the bills. But in this approach, malicious consumers who send erroneous data to take advantage or disrupt smart grid cannot be identified. In this paper, we propose a new statistical-based scheme for data gathering and billing in which the privacy of consumers is preserved, and at the same time, if any consumer with erroneous data can be detected. Our simulation results verify these matters.
Along with the development of information technology, the traditional electrical grid is moving to smart grid technology. By using the smart grid, the users and utility providers can more efficiently manage and generate power. Along with the advantages, the smart grid is also faced with new security concerns. In the smart grid, the user's citizen identity information should be preserved and the offensive user should be traced. For some low-capacity devices, it is indispensable to perform complicated computation by using outsourcing computation. The authors provide the outsourcing computation through public cloud. Anonymity and traceability are two important security properties in the smart grid. They are the unity of opposites. On the basis of the security requirements, they propose the balanced anonymity and traceability for outsourcing small-scale data linear aggregation (BAT-LA) in the smart grid. The formal definition, system model and security model are presented. Then, a concrete BAT-LA protocol is designed by using the elliptic curve cryptography and proxy re-encryption. Through security analysis and performance analysis, the designed BAT-LA protocol is provably secure and efficient. Abstract In a cyber-physical system, the control component plays an essential role to make the cyber and physical components work harmoniously together. When information collected from the physical space contains private or sensitive data that cannot be passed onto the cyber space, properly controlling the cyber-physical system becomes a very challenging task. For instance, the smart grid systems, a replacement for the traditional power grid systems, have been widely used in the industries. To prevent power shortage, threshold-based power usage control (PUC) in a smart grid considers a situation where the utility company sets a threshold to control the total power usage or supply of a neighborhood. If the total power usage exceeds the threshold, either certain households need to reduce their power consumption or the utility company needs to buy additional power supplies to meet the increasing demand. In these scenarios, the utility company needs to frequently collect power usage data from smart meters. It has been well documented that these power usage data can reveal a person's daily activity and violate personal privacy. To mitigate the privacy concerns, the goal of this paper is to develop efficient and privacy-preserving power usage control protocols that allow a utility company to balance supply and demand in a smart grid without violating personal privacy of its customers. We will provide extensive empirical study to show the practicality of our proposed protocols. Abstract With the proliferation of smart grids, traditional utilities are struggling to handle the increasing amount of metering data. Outsourcing the metering data to heterogeneous distributed systems has the potential to provide efficient data access and processing. In an untrusted heterogeneous distributed system environment, employing data encryption prior to outsourcing can be an effective way to preserve user privacy. However, how to efficiently query encrypted multidimensional metering data stored in an untrusted heterogeneous distributed system environment remains a research challenge. In this paper, we propose a high performance and privacy-preserving query (P2Q) scheme over encrypted multidimensional big metering data to address this challenge. In the proposed scheme, encrypted metering data are stored in the server of an untrusted heterogeneous distributed system environment. A Locality Sensitive Hashing (LSH) based similarity search approach is then used to realize the similarity query. To demonstrate utility of the proposed LSH-based search approach, we implement a prototype using MapReduce for the Hadoop distributed environment. More specifically, for a given query, the proxy server will return K top similar data object identifiers. An enhanced Ciphertext-Policy Attribute-based Encryption (CP-ABE) policy is then used to control access to the search results. Therefore, only the requester with an authorized query attribute can obtain the correct secret keys to retrieve the metering data. We then prove that the P2Q scheme achieves data confidentiality and preserves the data owner’s privacy in a semi-trusted cloud. In addition, our evaluations demonstrate that the P2Q scheme can significantly reduce response time and provide high search efficiency without compromising on search quality (i.e. suitable for multidimensional big data search in heterogeneous distributed system, such as cloud storage system).