Tamper-proof data storage

In a data processing system, stored data that is essential to a given data processing operation, such encryptographic key generation, is tamper proof in that if such data is altered, processing of the altered data is inhibited upon retrieval. The system includes a memory for storing a plurality of data bits and in which the storage of one type of the bits is irreversible; a data processor, such as a cryptographic processor, coupled to the memory for retrieving the bits from a first section of the memory and for processing the retrieved bits with other data bits; an authentication unit coupled to the memory for processing the bits stored in the first section of the memory with bits stored in a second section of the memory to provide an indication as to whether or not the bits stored in the first section of the memory have a predetermined relationship to the bits stored in the second section of the memory; and a gate coupled to the data processor and to the authentication unit for inhibiting the data processor from processing the data bits retrieved from the first section of the memory unless the authentication unit indicates that the bits stored in the first section of the memory have the predetermined relationship to the bits stored in the second section of the memory. Since storage of one type of the bits is irreversible, although a pirate can alter the logic state of one type of bit in one section of the memory, he cannot alter the the logic state of the other type of bit in the other of the memory so as restore the predetermined relationship between the bits in the first section of the memory and the bits in the second section of the memory.