TY - GEN

T1 - Fully homomorphic encryption with table lookup for privacy-preserving smart grid

AU - Li, Ruixiao

AU - Ishimaki, Yu

AU - Yamana, Hayato

PY - 2019/6

Y1 - 2019/6

N2 - Smart grids are indispensable applications in smart connected communities (SCC). To construct privacy-preserving anomaly detection systems on a smart grid, we adopt fully homomorphic encryption (FHE) to protect users' sensitive data. Although FHE allows a third party to perform calculations on encrypted data without decryption, FHE only supports addition and multiplication on encrypted data. In anomaly detection, we must calculate both harmonic and arithmetic means consisting of logarithms. A naïve implementation of such arithmetic operations with FHE is a bitwise operation; thus, it requires huge computation time. To speed up such calculations, we propose an efficient protocol to evaluate any functions with FHE using a lookup table (LUT). Our protocol allows integer encoding, i.e., a set of integers is encrypted as a single ciphertext, rather than using bitwise encoding. Our experimental results in a multi-threaded environment show that the runtime of our protocol is approximately 51 s when the size of the LUT is 448,000. Our protocol is more practical than the previously proposed bitwise implementation.

AB - Smart grids are indispensable applications in smart connected communities (SCC). To construct privacy-preserving anomaly detection systems on a smart grid, we adopt fully homomorphic encryption (FHE) to protect users' sensitive data. Although FHE allows a third party to perform calculations on encrypted data without decryption, FHE only supports addition and multiplication on encrypted data. In anomaly detection, we must calculate both harmonic and arithmetic means consisting of logarithms. A naïve implementation of such arithmetic operations with FHE is a bitwise operation; thus, it requires huge computation time. To speed up such calculations, we propose an efficient protocol to evaluate any functions with FHE using a lookup table (LUT). Our protocol allows integer encoding, i.e., a set of integers is encrypted as a single ciphertext, rather than using bitwise encoding. Our experimental results in a multi-threaded environment show that the runtime of our protocol is approximately 51 s when the size of the LUT is 448,000. Our protocol is more practical than the previously proposed bitwise implementation.

KW - Fully homomorphic Encryption

KW - Function evaluation

KW - Smart grid

KW - Table lookup

UR - http://www.scopus.com/inward/record.url?scp=85070860068&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85070860068&partnerID=8YFLogxK

U2 - 10.1109/SMARTCOMP.2019.00023

DO - 10.1109/SMARTCOMP.2019.00023

M3 - Conference contribution

AN - SCOPUS:85070860068

T3 - Proceedings - 2019 IEEE International Conference on Smart Computing, SMARTCOMP 2019

SP - 19

EP - 24

BT - Proceedings - 2019 IEEE International Conference on Smart Computing, SMARTCOMP 2019

PB - Institute of Electrical and Electronics Engineers Inc.

T2 - 5th IEEE International Conference on Smart Computing, SMARTCOMP 2019

Y2 - 12 June 2019 through 14 June 2019

ER -