Enhanced digital signature using RNS digit exponent representation

Authors

Thomas Plantard, University of WollongongFollow
Jean-Marc Robert, University of Perpignan

RIS ID

113083

Publication Details

Plantard, T. & Robert, J. (2017). Enhanced digital signature using RNS digit exponent representation. Lecture Notes in Computer Science, 10064 177-192. Ghent, Belgium 6th International Workshop: Arithmetic of Finite Fields (WAIFI 2016)

Abstract

Springer International Publishing AG 2016.Digital Signature Algorithm (DSA) involves modular exponentiation, of a public and known base by a random one-time exponent. In order to speed-up this operation, well-known methods take advantage of the memorization of base powers. However, due to the cost of the memory, to its small size and to the latency of access, previous research sought for minimization of the storage. In this paper, taking into account the modern processor features and the growing size of the cache memory, we improve the storage/efficiency trade-off, by using a RNS Digit exponent representation. We then propose algorithms for modular exponentiation. The storage is lower for equivalent complexities for modular exponentiation computation. The implementation performances show significant memory saving, up to 3 times for the largest NIST standardized key sizes compared to state of the art approaches.