V.A. Raikhlin, I.S. Vershinin

The results of modelling researches of the two-dimensional-associative approach to masking (protection) of the distributed dot objects of cartography are systematized as a special case of stencil way in classical steganography. The substantiation of this approach is exemplified on the basis of an admissibility systems of Shennon`s criterion of logic interpretation which is established from the positions of constructive modelling. The principles and algorithms of steganography protection by masking method are reviewed. The guidelines for key sizes matching and the assessment of computing security of the method is given. The strategy of proceeding work is shown. The basic difference of an offered way of protection from the other known methods is representation of digital symbols in the binary matrixes form of certain sizes. This method suggests the introduction of pseudo-casual process in the transmitted message, under the stipulation that the limited subset of bits in each sign with casual distribution of mentioned subset in a bit grid of its standard remains true. In this case the key is the set of masks for every possible figures. GAMMA presence does not affect the fact of the authorised recognition, but creates almost insuperable barrier for the opponent. The proposed systematization allows to consider that the developed approach should take a worthy place among effective methods of protection of the cartographical data.