The encryption algorithm "FC" and analysis of its avalanche effect criterion

Abstract

The article is about the importance, features and scope of symmetric block ciphers used to ensure the
confidentiality of data in the era of rapid development of modern computing technologies. In this paper, the structure of
the symmetric block encryption algorithm CF, developed in the "Laboratory of Information Security" of the "Institute of
Information and Computational Technologies", the round keys generating mechanism based on it’s secret key are described. A computer program of the created encryption algorithm was developed, on the basis of which the performance was studied
and the bit scattering between the plaintext and the ciphertext (the property of the "avalanche effect" and "strong avalanche
effect") was checked. In order to optimize the hardware implementation of the algorithm, the conversion of the S-block,
which is considered as a nonlinear node, was obtained in 4x4 bit size.