Introducing secure modes of operation for optical encryption

Abstract

We analyze optical encryption systems using the techniques of conventional cryptography. All conventional block encryption algorithms are vulnerable to attack, and often they employ secure modes of operation as one way to increase security. We introduce the concept of conventional secure modes to optical encryption and analyze the results in the context of known conventional and optical attacks. We consider only the optical system "double random phase encoding," which forms the basis for a large number of optical encryption, watermarking, and multiplexing systems. We consider all attacks proposed to date in one particular scenario. We analyze only the mathematical algorithms themselves and do not consider the additional security that arises from employing these algorithms in physical optical systems.

Keywords: 060.4785 Fiber optics and optical communications : Optical security and encryption, 100.4998 Image processing : Pattern recognition, optical security and encryption, 070.2580 Fourier optics and signal processing : Paraxial wave optics, 070.4560 Fourier optics and signal processing : Data processing by optical means.

Copyright 2008 OSA. This paper was published in Journal of the Optical Society of America A and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://josaa.osa.org/abstract.cfm?uri=josaa-25-10-2608. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.