THE IMPROVEMENT OF NTRUENCRYPT PUBLIC KEY CRYPTOSYSTEM: DESIGN AND PERFORMANCE EVALUATION

Today cryptographic systems provide secure communication between users. In the present paper we describe existing cryptographic systems such as: systems based on the complexity of factorization of a large integer (RSA); systems based on the complexity of solving a discrete logarithm in finite Galois field (eigamal, DSA); systems based on the complexity of solving a discrete logarithm in a group of points of an elliptic curve (ECC); lattice-based systems (NTRU). Authors focus their attention on ntruencrypt encryption and decryption algorithm. The ntruencrypt public key cryptosystem guarantees the integrity and confidentiality of information when transmitting, storing and processing information messages in modern computer systems and networks. The conducted studies of public key cryptosystem made it possible to determine the way of the improve ntruencrypt public key cryptosystem. In this paper, we present improved ntruencrypt public key cryptosystem which is based on the correct selection of parameters p and q. The authors concluded that, to reduce the difference between the length of ciphertext and plaintext, it is necessary to take p and q closer to each other. At the same time it