Patent ID: 7451325

Claim:
A method of detecting tampering of electronic equipment, the method comprising: dividing a known software image into a plurality of software image portions; arranging the software image portions in a first ordering; instructing the electronic equipment to perform a first sequence of hashing algorithms on the plurality of software image portions according to the first ordering to provide a sequence of first hash results, wherein a respective first hash result corresponds to a respective hashing algorithm of the first sequence and a respective software image portion of the first ordering; detecting tampering if the sequence of first hash results is not provided within a first timeout period; arranging the software image portions in a second ordering different from the first ordering; instructing the electronic equipment to perform a second sequence of hashing algorithms different from the first sequence on the plurality of software image portions according to the second ordering to provide a sequence of second hash results, wherein a respective second hash result corresponds to a respective hashing algorithm of the second sequence and a respective software image portion of the second ordering; and detecting tampering if the sequence of second hash results is not provided within a second timeout period.