Molecular MUX-Based Physical Unclonable Functions

TL;DR

This paper introduces molecular PUFs based on multiplexer circuits using molecular reactions, demonstrating their potential for hardware security with increased stages improving reliability and uniqueness.

Contribution

First presentation of molecular PUFs utilizing molecular reactions for randomness, expanding the scope of physical unclonable functions into molecular computing.

Findings

Molecular PUFs with 16 or more stages are effective for security.

Increasing stages enhances PUF reliability and uniqueness.

8-stage molecular PUFs are not suitable as PUFs.

Abstract

Physical unclonable functions (PUFs) are small circuits that are widely used as hardware security primitives for authentication. These circuits can generate unique signatures because of the inherent randomness in manufacturing and process variations. This paper introduces molecular PUFs based on multiplexer (MUX) PUFs using dual-rail representation. It may be noted that molecular PUFs have not been presented before. Each molecular multiplexer is synthesized using 16 molecular reactions. The intrinsic variations of the rate constants of the molecular reactions are assumed to provide inherent randomness necessary for uniqueness of PUFs. Based on Gaussian distribution of the rate constants of the reactions, this paper simulates intra-chip and inter-chip variations of linear molecular MUX PUFs containing 8, 16, 32 and 64 stages. These variations are, respectively, used to compute reliability and uniqueness. It is shown that, for the rate constants used in this paper, although 8-state molecular MUX PUFs are not useful as PUFs, PUFs containing 16 or higher stages are useful as molecular PUFs. Like electronic PUFs, increasing the number of stages increases uniqueness and reliability of the PUFs