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The Security Enhancement Techniques of the Double-layer PUF Against the ANN-based Modeling Attack

The physical unclonable function (PUF) against the modeling attack is of great concern in recent years, since the modeling attack has been proved to be a serious security threat to the PUF circuits. The double-layer PUF was reported as a PUF scheme to resist the fully connected artificial neural network based modeling attack, and its test chip was fabricated and tested. This work proposes an artificial neural network (ANN) based modeling method according to the working principle of the target PUF, and successfully attacks the double-layer PUF. To enhance the anti-modeling-attack capability of the double-layer PUF, the address swapping, the XORing, and the dimensional extension techniques are proposed. The attack results show that the prediction accuracy of the proposed ANN-based model with the proposed techniques drops obviously. And the prediction accuracy is about 50.04% if all the three proposed techniques are applied in combination. It manifests that the proposed security enhancement techniques are able to improve the resilience of the double-layer PUF against the modeling attacks effectively. Both the randomness and uniqueness of the improved doublelayer PUFs are approximate to the ideal value (50%), and the reliability of the improved PUFs remain unchanged compared with the original counterpart because the operations on the resistive random memory (RRAM) array are the same.