Authentication and Confidentiality is the main goal of the public key cryptosystems deal when communication takes place between both the parties. The mostly used cryptographic methods are broadly classified as symmetric and asymmetric. The DES comes under the category of symmetric key cryptosystem whereas RSA, NTRU[1] belongs to the category of asymmetric key cryptosystem. NTRU (Nth degree trun...

We show a novel lattice-based scheme (PairTRU) which is a non-commutative variant of the NTRU. The original NTRU is defined via the ring of quotient with variable in integers and this system works in the ring R = Z[x] . We extend this system over Z× Z and it performs all of operations in the non-commutative ring M = M(k,Z×Z)[x] <(Ik×k,Ik×k)x−(Ik×k,Ik×k)> , where M is a matrix ring of k ×...

In this paper we present a new algorithm to attack lattice based cryptosystems by solving a problem over real numbers. In the case of the NTRU cryptosystem, if we assume the additional information on the modular operations, we can break the NTRU cryptosystems completely by getting the secret key. We believe that this fact was not known before.

In this paper we will construct a lattice-based public-key cryptosystem using non-commutative quaternion algebra, and since its lattice does not fully fit within Circular and Convolutional Modular Lattice (CCML), we prove it is arguably more secure than the existing lattice-based cryptosystems such as NTRU. As in NTRU, the proposed public-key cryptosystem relies for its inherent securi...

NTRU is a very efficient public-key cryptosystem based on polynomial arithmetic. Its security is related to the hardness of lattice problems in a very special class of lattices. This article is motivated by an interesting peculiar property of NTRU lattices. Namely, we show that NTRU lattices are proportional to the so-called symplectic lattices. This suggests to try to adapt the classical reduc...

In 1996, a new cryptosystem called NTRU was introduced, related to the hardness of finding short vectors in specific lattices. At Eurocrypt 2001, the NTRU Signature Scheme (NSS), a signature scheme apparently related to the same hard problem, was proposed. In this paper, we show that the problem on which NSS relies is much easier than anticipated, and we describe an attack that allows efficient...

Xinyu et al. proposed a public key exchange protocol, which is based on the NTRU-lattice based cryptography. In this paper, we show how Xinyu et al.’s NTRU-KE: A lattice based key exchange protocol can be broken, under the assumption that a man-in-the middle attack is used for extracting private keys of users who participate in the key exchange protocol.

RSA and Bell Labs [2, 3] have recently announced a potential attack on certain public key protocols, along with several suggested countermeasures. The most secure of these countermeasures uses the concept of plaintext aware, which means that it should be infeasible to construct a valid ciphertext without knowing the corresponding plaintext. Failure to be plaintext aware may open a cryptosystem ...