RISKE, A NOVEL CPA-SECURE SECRET-KEY ENCRYPTION SCHEME BASED-ON INVERTIBLE ELEMENTS IN BINARY QUOTIENT POLYNOMIAL RINGS

Abstract

Invertible elements in quotient polynomial rings have been exploited to construct some interesting public-key cryptosystems such as NTRU and pNE. In this paper, we first introduce a special class of binary quotient polynomial rings in which the set of invertible elements is very large. By exploiting that set, we propose a novel a secret-key encryption scheme which not only operate efficiently but also secure under the chosen plain-text attack (or CPA-secure).