A format-preserving encryption FF1, FF3-1 using lightweight block ciphers LEA and, SPECK

Abstract

Format-preserving encryption has been studied for a long time since its proposal, but the algorithm is yet to be adequately evaluated or verified. The existing standard format-preserving encryption FF1 and FF3-1 use block cipher AES in the internal function. This paper proposes a method to improve the speed of FF1 and FF3-1 whereby the algorithm is implemented by changing the cipher to lightweight block ciphers LEA(Lightweight Encryption Algorithm) and SPECK. The encryption speed is analyzed and compared with that of the existing encryption by dividing it into high-performance computer environments and low-performance Internet of Things environments. The results showed that the encryption speed was improved compared with FF1 and FF3-1. Improving the encryption speed of format-preserving encryption will make it easier to apply format-preserving encryption to various systems.