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Program Storage Scrambling

IP.com Disclosure Number: IPCOM000087243D
Original Publication Date: 1977-Jan-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Williams, RW: AUTHOR

Abstract

Security of the programming code set for an initial program load data processing machine, including a random-access memory, is provided by: (1) Filling the memory with a predetermined sequence of random numbers provided by a read-only storage random number generator; and (2) Inputting a sequence of memory-modifying bytes into the memory to modify the storage locations in the memory, according to the desired machine instructions.

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Program Storage Scrambling

Security of the programming code set for an initial program load data processing machine, including a random-access memory, is provided by: (1) Filling the memory with a predetermined sequence of random

numbers provided by a read-only storage random number generator;

and

(2) Inputting a sequence of memory-modifying bytes into the

memory to modify the storage locations in the memory, according

to the desired machine instructions.

The memory-modifying bytes, therefore, are not machine instructions from the code set that could be recognized if the bytes were printed or otherwise inspected. The machine instructions include the random bytes initially loaded into the memory as modified by the input bytes.

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