Patent ID: 8416950

Claim:
A method of securing communication of data between an integrated circuit device and an external device, the method comprising: generating, by the integrated circuit device, a fingerprint, wherein the fingerprint is reproducible and represents an inherent manufacturing process characteristic unique to the integrated circuit device; receiving encrypted data from the external device; generating a decryption key based on the fingerprint; and decrypting, using the decryption key, the encrypted data to extract the data, wherein generating the fingerprint comprises one of: determining whether a width of each of a plurality of line segments is less than a predetermined value, and generating a width value based on the act of determining, wherein the fingerprint is based on the width value; or counting a first number of oscillations of a first oscillator during a predetermined time interval and counting a second number of oscillations of a second oscillator during the predetermined time interval, and generating a ratio between the first number and the second number, wherein the ratio represents the fingerprint; or determining whether a first transistor or a second transistor of each of a plurality of transistor pairs turns on earlier by detecting current flow in the first transistor and the second transistor, and generating a turn-on value based on which one of the first transistor or the second transistor of each of the plurality of transistor pairs was determined to turn on earlier, wherein the fingerprint is based on the turn-on value.