A Performance Analysis and Evaluation of SIDH with Implementation-Friendly Classes of Quadratic Extension Fields

Abstract

It is well-known that the class of binomial extension fields is widely used to construct quadratic extension fields (QEFs) of supersingular isogeny Diffie-Hellman (SIDH) key exchange protocol. There is a possibility to improve the performance of SIDH by employing other classes of QEFs, i.e., extension fields with normal basis and all-one polynomial extension fields, without sacrificing the range of primes. In this paper, the authors confirm that the applicability of the other classes for SIDH and evaluate the computational complexity of the large-degree isogenies required for SIDH. The results of the experiments show that the performances with the classes are comparable to the QEF with a binomial x^2+1.