Towards a realistic channel model for security analysis of authentication using graphical codes

Graphical codes resemble very much the well-known QR-codes, although they are used in a very different application scenario: authenticating and tracing physical goods on which they are printed with small dimensions so as to become uncloneable. In this paper, we propose a security analysis of such codes based on a realistic channel model. We show that the security level of such codes heavily depends on the printing resolution. For the first time, our experimental setup enables to assess the maximum number of graphical codes to be safely printed until a security breach occur in the authentication system.