ВДОСКОНАЛЕННЯ КРИПТОСИСТЕМИ NTRUENCRYPT: ПРОЕКТУВАННЯ ТА ОЦІНКА ЕФЕКТИВНОСТІ

Abstract

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 is necessary to consider that at too close values p and q the cryptosystem can be weakened. The main difference between the proposed schemes was the reducing the size of ciphertext which can minimizes the time for software encryption and decryption operations. As a result is a software implementation of the procedure for the encryption and decryption of the improve ntruencrypt public key cryptosystem using a programming language Ruby 1.9.3 was obtained using the cryptolib library. Improved algorithm will be a perfect tool for ensuring the confidentiality of information, using “cloud” computing, because protecting information from unauthorized access is one of the most pressing problems. The authors further plan a number of scientific and technical solutions to develop and implement effective methods, tools to meet the requirements, principles and approaches to cyber security and cryptosystems for provide integrity and confidentiality of information in experimental computer systems and networks.