Information security with optical means, such as double random phase encoding, has been investigated by various researchers. It has been demonstrated that optical technology possesses several unique characteristics for securing information compared with its electronic counterpart, such as many degrees of freedom. In this paper, we present a review of optical technologies for information security. Optical security systems are reviewed, and theoretical principles and implementation examples are presented to illustrate each optical security system. In addition, advantages and potential weaknesses of each optical security system are analyzed and discussed. It is expected that this review not only will provide a clear picture about current developments in optical security systems but also may shed some light on future developments.
Information security with optical means, such as double random phase encoding, has been investigated by various researchers. It has been demonstrated that optical technology possesses several unique characteristics for securing information compared with its electronic counterpart, such as many degrees of freedom. In this paper, we present a review of optical technologies for information security. Optical security systems are reviewed, and theoretical principles and implementation examples are presented to illustrate each optical security system. In addition, advantages and potential weaknesses of each optical security system are analyzed and discussed. It is expected that this review not only will provide a clear picture about current developments in optical security systems but also may shed some light on future developments.
In the modern era, the secure transmission and storage of information are among the utmost priorities. Optical security protocols have demonstrated significant advantages over digital counterparts, i.e., a high speed, a complex degree of freedom, physical parameters as keys (i.e., phase, wavelength, polarization, quantum properties of photons, multiplexing, etc.) and multi-dimension processing capabilities. This paper provides a comprehensive overview of optical cryptosystems developed over the years. We have also analyzed the trend in the growth of optical image encryption methods since their inception in 1995 based on the data collected from various literature libraries such as Google Scholar, IEEE Library and Science Direct Database. The security algorithms developed in the literature are focused on two major aspects, i.e., symmetric and asymmetric cryptosystems. A summary of state-of-the-art works is described based on these two aspects. Current challenges and future perspectives of the field are also discussed.
Optical systems as information processing systems have become quite impressive recently in optical image encryption and watermarking. Benefits of optical systems over the electronic counterparts are that optical processing provides the maximum number of degrees of freedom, and that optical encryption is ideal for information stored in holographic media. Various schemes have been proposed in the last decade. In this article, we review the recent progress and patents in this field, and point out some challenges that might lead to practical optical information security systems Keywords: Double random phase encoding, holography, information security, Optical encryption, phase retrieval, Optical systems, multidimensional information s, spatial coherence, polarization, Optical image encryption, cryptosystem, discrete fractional fourier transform, encoding technique, micro-optics system, decryption method
As a typical technology for optical encryption, phase retrieval algorithms have been widely used in optical information encryption and authentication systems. This paper presents three applications of two-dimensional (2D) phase retrieval for optical encryption and authentication: first, a hierarchical image encryption system, by which multiple images can be hidden into cascaded multiple phase masks; second, a multilevel image authentication system, which combines (t, n) threshold secret sharing (both t and n are positive integers, and t ≤ n ) and phase retrieval, and provides both high-level and low-level authentication; and finally, a hierarchical multilevel authentication system that combines the secret sharing scheme based on basic vector operations and the phase retrieval, by which more certification images can be encoded into multiple cascaded phase masks of different hierarchical levels. These three phase retrieval algorithms can effectively illustrate phase-retrieval-based optical information security. The principles and features of each phase-retrieval-based optical security method are analyzed and discussed. It is hoped that this review will illustrate the current development of phase retrieval algorithms for optical information security and will also shed light on the future development of phase retrieval algorithms for optical information security.
Abstract Information security and authentication are important challenges facing society. Recent attacks by hackers on the databases of large commercial and financial companies have demonstrated that more research and development of advanced approaches are necessary to deny unauthorized access to critical data. Free space optical technology has been investigated by many researchers in information security, encryption, and authentication. The main motivation for using optics and photonics for information security is that optical waveforms possess many complex degrees of freedom such as amplitude, phase, polarization, large bandwidth, nonlinear transformations, quantum properties of photons, and multiplexing that can be combined in many ways to make information encryption more secure and more difficult to attack. This roadmap article presents an overview of the potential, recent advances, and challenges of optical security and encryption using free space optics. The roadmap on optical security is comprised of six categories that together include 16 short sections written by authors who have made relevant contributions in this field. The first category of this roadmap describes novel encryption approaches, including secure optical sensing which summarizes double random phase encryption applications and flaws [Yamaguchi], the digital holographic encryption in free space optical technique which describes encryption using multidimensional digital holography [Nomura], simultaneous encryption of multiple signals [Pérez-Cabré], asymmetric methods based on information truncation [Nishchal], and dynamic encryption of video sequences [Torroba]. Asymmetric and one-way cryptosystems are analyzed by Peng. The second category is on compression for encryption. In their respective contributions, Alfalou and Stern propose similar goals involving compressed data and compressive sensing encryption. The very important area of cryptanalysis is the topic of the third category with two sections: Sheridan reviews phase retrieval algorithms to perform different attacks, whereas Situ discusses nonlinear optical encryption techniques and the development of a rigorous optical information security theory. The fourth category with two contributions reports how encryption could be implemented at the nano- or micro-scale. Naruse discusses the use of nanostructures in security applications and Carnicer proposes encoding information in a tightly focused beam. In the fifth category, encryption based on ghost imaging using single-pixel detectors is also considered. In particular, the authors [Chen, Tajahuerce] emphasize the need for more specialized hardware and image processing algorithms. Finally, in the sixth category, Mosk and Javidi analyze in their corresponding papers how quantum imaging can benefit optical encryption systems. Sources that use few photons make encryption systems much more difficult to attack, providing a secure method for authentication.
Optical information security techniques are developed at a fast pace over the past two decades. In the present scenario, where enormous amount of data is being exchanged, information security plays an important role in protecting the information/data from unauthorized use/access. In this context, securing information using optical means has become relevant, given the suitable features of speed and multiple degrees of freedom that optical cryptosystems offer. Asymmetric cryptosystems have been introduced as an upgrade over the conventional double random phase encoding technique and they show resistance towards the known-plaintext attack. This paper reviews the symmetric and asymmetric cryptosystems and their attack analysis.
Optical information security is one of the most important research directions in information science and technology, especially in the copyright protection, confidential information transmission/storage and military remote sensing. Since double random phase encoding technology (DRPE) was proposed, optical image encryption technology has become the main topic of optical information security and it has been developed and studied deeply. Much significant research and investigation on optical image encryption have been presented based on DRPE or further optical operation, such as digital holography, and Fresnel transform, gyrator transform. In this paper, the optical encryption system for gray image and color image is reviewed.