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Showing papers on "Block cipher published in 1980"


Patent
17 Jan 1980
TL;DR: In this paper, a cryptographic microprocessor for processing data and executing programs which are stored in enciphered blocks to prevent unauthorized alteration and copying is described, and combined use of block and byte deciphering is described.
Abstract: A cryptographic microprocessor for processing data and executing programs which are stored in enciphered blocks to prevent unauthorized alteration and copying. Such a "crypto-microprocessor" deciphers the enciphered program and data blocks piecemeal as execution of the deciphered program proceeds. A product block cipher circuit makes each bit of a deciphered block a complicated function of each bit of an enciphered block, and each bit of an encryption key, and each bit of the digital address of the enciphered block. Combined use of block and byte deciphering is described. If a block of the enciphered program is altered, the crypto-microprocessor temporarily or permanently disables itself.

162 citations