| 摘要 |
System and method for verifying the integrity of contents within a computer file (5). A security value S is stored within the file (5). A verification function f is applied against the entire contents of the file (5) including S, where f is a function of S. Results R of the applying step are compared against a preselected value r, where r is not stored within the file (5). When R equals r, a determination is made that the file (5) has not been modified. f is typically a distributive invertible function such as the Cyclic Redundancy Check (CRC) function known as modulo p, where p is a prime number and is one bit greater than the length of S. Typically, the value of r is zero. Before executing the verification function f, a check generating program is first executed. This check generating program is executed by a computer (4) that is remote from the file (5), further enhancing the security of the system.
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