Date of Award


Document Type


Degree Name

Master of Science in Electrical Engineering


Department of Electrical and Computer Engineering

First Advisor

Yong C. Kim, PhD


Commercial off-the-shelf (COTS) component usage is becoming more prevalent in military applications due to current Department of Defense (DoD) policies. The easy accessibility of COTS will give reverse engineers a higher probability of successfully tampering, coping, or reverse engineering circuits that contain critical capabilities. To prevent this and verify the trustworthiness of hardware, circuit identification tags or serials numbers can be used. However, these values can be easily obtained and forged. To protect critical DoD technologies from possible exploitation, there is an urgent need for a reliable method to confirm a circuit’s identity using a set of unique unforgettable metrics. This research proposes the concept of creating a circuit identifier, or digital fingerprint, for application specific integrated circuits (ASIC) and field programmable gate arrays (FPGAs). The digital fingerprint would be a function of the natural variations in the semiconductor manufacturing process and the functionality of the circuit allowing the creation of a unique identifier for a specific chip that can not be duplicated or forged. The proposed digital fingerprint allows the use of any arbitrary node or set of nodes internal to the circuit and the circuit outputs as monitoring locations. Changes in the signal on a selected node or output can be quantified digitally over a period of time or at a specific instance of time. Two monitoring methods are proposed, one using cumulative observation of the nodes and the other samples the nodes based on a signal transition. Testing of the two monitoring methods was performed on a small sample of twenty Xilinx® Virtex-II Pro FPGAs. Both methods successfully created unique identifiers for each FPGA.

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