1.  Field of the Disclosure
The present disclosure relates generally to anti-counterfeit systems and more particularly to physical unclonable functions. 
2.  Description of the Related Art
Counterfeit printer supplies, such as toner bottles, are a problem for consumers.  Counterfeit supplies may perform poorly and may damage printers.  Printer manufacturers use authentication systems to deter counterfeiters.  Physical unclonable functions (PUF) are a type of authentication system that implements a physical one-way function.  Ideally, a PUF cannot be identically replicated and thus is difficult to counterfeit.  Thus, it is advantageous to maximize the difficulty of replicating a PUF to deter counterfeiters.  It is also advantageous for the PUF and PUF reader to be low cost.