Cryptanalysis of ITRU

Abstract

ITRU cryptosystem is a public key cryptosystem and one of the known variants of NTRU cryptosystem. Instead of working in a truncated polynomial ring, ITRU cryptosystem is based on the ring of integers. The authors claimed that ITRU has better features comparing to the classical NTRU, such as having a simple parameter selection algorithm, invertibility, and successful message decryption, and better security. In this paper, we present an attack technique against the ITRU cryptosystem, and it is mainly based on a simple frequency analysis on the letters of ciphertexts.

An overview of number theory research unit variant development security

“…In the NTRU cryptosystem, the key generation is more than 200 times faster than in the Rivest-Shamir-Adleman (RSA) cryptosystem, and the encryption is almost 3 times faster. The decryption is about 30 times faster [7] Preliminary results was showed on the working [8]. Some variants of NTRU, like Construction Throy Research Unit (CTRU), Quaternionic Theory Research Unit (QTRU), Matrix Formulation (MaTRU), Eisenstein Throy Research Unit (ETRU), a noncommutative analogue of NTRU (NNRU), Ideal lattices Throy Research Unit (ILTRU), and others are called NTRU variants [2].…”