Redundant Metering for Integrity with Information-Theoretic Confidentiality

Redundant metering is frequently used to verify the integrity of billing data reported by advanced metering infrastructure, but the redundant measurement introduces a potential confidentiality leak. We propose a way to encode the redundant measurement at a bit rate below its entropy, so that it cannot be decoded from the encoded bits alone. In this way, we guarantee information-theoretic confidentiality, regardless of the computational power of an eavesdropper. We provide practical Slepian-Wolf codes to realize security of up to 5 bit/sample for 8-bit samples based on actual power metering experiments.