Assessing the feasibility of fully homomorphic encryption for Smart Grid AMI networks

Despite the potential benefits of smart meters as part of the Smart Grid initiative, the deployment of smart meters has aroused several concerns on consumer privacy. To address such concerns, various solutions are proposed in recent years under a variety of assumptions. Nonetheless, all of these solutions require a trust relationship between the consumers and utilities or third-party service providers which still does not convince some of the consumers for using smart meters. An ultimate solution is to hide the data from utilities or third-parties by using fully homomorphic encryption (FHE) systems while still allowing them to do processing on the encrypted data for their needs. However, the FHE systems are recently started to be realized and their wider deployment for certain applications has not been explored yet. In this paper, we investigate the feasibility of using FHE systems on an IEEE 802.11s-based Advanced Metering Infrastructure (AMI) application when preserving the privacy of the consumers. We design and adapt one of the existing FHE schemes for AMI and test its overhead under a variety of conditions on an 802.11s-based wireless mesh network using ns-3 network simulator. Compared to traditional encryption and partially homomorphic systems, FHE comes with significant overhead in terms of data size and delay. Nevertheless, the results indicate that such delay and data size overhead are still in acceptable limits that can be handled by the existing meters and networks.