Challenge-Response Pair (CRP) Generator Using Schmitt Trigger Physical Unclonable Function

Physically unclonable function (PUF), a hardware security module, generates a unique response for each challenge by embodying a hardware feature into the computation. In the proposed Schmitt trigger(ST)-based PUF, the response is a function of circuit-based two different feature; triggering nature of ST generates a defined saturation level for changing input, and delay rises through cascading structure of STs. Multi-feature-based PUF sustains better unclonability and retains average reliability 99.725% with temperature variation, 99.86 with supply variation, and average uniqueness 47%. Another part of work is to enhance the response rate; rising and falling input sample individually generates five responses for rising and five responses for falling input. The proposed ST-PUF can generate ten numbers of 32-bit responses in one input period, and it enhances response generation rate by 10 times.