摘要 |
The invention relates to telecommunication and information technology. The invention comprises a method for cryptographic protection of an item of information and a device for performing said method. The inventive device comprises the following elements: a data conversion unit (1) with a coder (4) incorporated therein and converting an input fill (X) on a communication key (K) into a coded fill (A); an n-bit linear shift register (5) with a back action, forming a stream of a temporary long-period binary bit sequence (B); a time delay unit (6) forming a stream of a temporary long period binary bit sequence (C) with a discontinuous length; a multiplexor (10) dividing a volume of said sequence (C) into two parts, one being a temporary fill (D) and another being a temporary key (E); an unit (2) for gamma production with a coder (7) incorporated therein and coding the temporary fill (D), with the aid of a block cipher, on the temporary key (E), thus obtaining gamma blocks (H); a compression unit (11) converting the gamma blocks (H) into compressed gamma blocks (H'); a block (3) for coding input data and comprising a register (8) which converts input data (M0), with formation of data blocks (M'); a compression unit (12) performing a compressed conversion producing compressed data blocks (M), and a totalizator (9) coding the input data by overlaying the compressed gamma blocks (H') on the compressed data blocks (M) and producing coded data. |