Abstract: A method of evaluating a cryptosystem to determine whether the cryptosystem can withstand a fault analysis attack, the method includes the steps of providing a cryptosystem having an encrypting process to encrypt a plaintext into a ciphertext, introducing a fault into the encrypting process to generate a ciphertext with faults, and comparing the ciphertext with the ciphertext with faults in an attempt to recover a key of the cryptosystem.

Abstract: A processing system includes a control flow monitor (CFM) checker for verifying a sequence of instructions performed by a pipelined processor (101). The CFM checker provides fail safe assurance against run-time errors in the sequence of instructions performed by a processor. The CFM checker verifies instruction sequence during run-time within 32 instruction cycles. The processing system provides an improved system and method having a CFM checker which minimizes wasted instruction cycles when performing branch instructions in a software program. Using a prefetch capability of an instruction pipeline and storing fixwords sequentially in memory, eliminates unnecessary instructions to fetch fixword values from external tables, thereby saving instructions and instruction cycles.