Purpose of research. The article examines the features of the synthesis of specialized devices that control the integrity and authenticity of individual information blocks based on CBC codes. Approaches aimed at reducing computational and resource costs when performing such procedures are considered. The dependencies between the performance indicators and the requirements for the volume of internal memory of specialized computers processing data in CBC mode are formulated..Methods. The implementation of data source authentication procedures using encoding in the mode of concatenation of individual data blocks is an effective method of increasing reliability in conditions of a limited size of verified authentication sequences. At the same time, its implementation in receivers requires the creation of specialized calculators that process tree-like structures that arise during data decoding, consisting of separate data blocks. To reduce resource and computational costs when processing such structures, indirect addressing is used, in which block data is stored in RAM, and their addresses are stored in the high-speed register memory of the computer itself.Results. A model of indirect addressing of data blocks in RAM has been created. Pointers to blocks are stored in a separate register memory and each pointer is placed according to the decoded sequence number of the block in the sequence. Each block address in RAM is supplemented by a set of pointers to subsequent blocks in the branches of the tree structure. The created mathematical model made it possible to estimate the size in bits of all the pointers involved and their number, which made it possible to determine the need for a computer processing a tree structure in register memory.Conclusion. The paper shows that using a combination of matrix and list organization of block address storage reduces the need for register memory of the calculator by 50-60%. At the same time, the computer can process the tree-like structure of information blocks using high-performance iterative algorithms, which would be impossible if only the list organization of address storage was used.