The model for constructing a set of symmetric two-operand set operations that allow perversion of operands by combining one-operand operations

The subject matter of the article is the scientific and methodological apparatus for constructing and implementing information-driven SET-operations. The goal of the work is to construct a model for the synthesis of symmetric two-operand SET-operations that allow permutation of operands and to determine the restrictions on their use in the development of low-resource stream ciphers. The following tasks are solved in the article: a model for the synthesis of symmetric two-operand SET-operations that allow permutation of operands is developed; restrictions on the use of this model are determined, which guarantee the construction of symmetric two-operand SET-operations that allow permutation of operands; it is shown that a pseudo-random change in the operating modes of the cryptographic system significantly complicates the processes of cryptanalysis of ciphergrams; modeling of SET-operations based on duplication of single-operand two-bit SET operations is carried out; the technology for constructing two-operand SET-operations based on duplication is applied to obtain a set of two-operand SET-operations. Methods of discrete mathematics, Set-theory and situational management have been introduced. Achieved results. Synthesized on the basis of this model of SET-operations allow changing the operating mode of stream cryptographic systems from symmetric to asymmetric when permuting operands in the operation. At present, the forefront of modern world experience in cryptographic science is a low-resource cryptographic system. Low-resource cryptography allows ensuring sufficiently stable cryptosystem performance with significant limitations on computational, mass-dimensional, cost and energy resources of the object of interest. One of the most relevant areas of further development of low-resource cryptography is considered to be cryptographic coding. In the process of cryptographic coding, cryptographic coding operations are implemented. The selection of operations is carried out under the control of a pseudo-random sequence, which is implemented by a cryptographic algorithm. Conclusions. A model for the synthesis of symmetric two-operand SET-operations that allow permutation of operands has been developed. Restrictions on the use of this model have been determined, which guarantee the construction of symmetric two-operand SET-operations that allow permutation of operands. The achieved results can be useful for the construction of low-resource stream encryption systems. Pseudo-random change of the operating modes of the cryptographic system significantly complicates the processes of cryptanalysis of ciphertexts.