Chosen-Plaintext Attacks of Double Random Phase Encryption with Nonlinear Optical Media
For researchers in optical encryption, this work reveals vulnerabilities in a proposed nonlinear DRPE scheme, showing that additional nonlinear parameters do not improve security against CPA.
This paper demonstrates that chosen-plaintext attacks can recover both the phase information and nonlinearity strength of a nonlinear optical encryption system combining DRPE, showing that including nonlinearity as a security key does not enhance protection against CPA, though strong nonlinearity still poses challenges.
This paper studies an inverse problem in nonlinear optical encryption. We examine chosen-plaintext attacks (CPA) on a nonlinear optical encryption strategy that integrates double random phase encryption (DRPE) into a nonlinear optical propagation model to enhance the security of the combined system. We first demonstrate that the system's phase information can be decoded from carefully designed differential CPA data. We then demonstrate that the strength of the optical device's nonlinearity can also be recovered from CPA data, indicating that including this parameter as an additional security key does not enhance protection against CPA attacks, although numerical simulations show that strong nonlinearity still poses significant challenges for CPA attacks. Finally, we provide a stability analysis to demonstrate that small errors in decoded security keys result in only small errors in the decrypted text, even though the encryption process is nonlinear.