Optical Encryption for Information Security

S.P. Yeo, Xudong Chen

Abstract : The research will focus on the underlying theory and methodologies to configure complex optical encryption networks for securing information. The goal is to study/develop the architectures for a number of complex optical encryption networks, and to provide effective and reliable solutions for information security.

Inbarasan Muniraj, John T. Sheridan

Hongtao Wang, Haoran Zhang, Xiaoyan Zhou +8 more

Xinshun Zhao, Ying Xu, ShuQin Lin +6 more

The rapid globalization of the digital ecosystem has elevated information security to a critical concern in modern society. Optical encryption offers an effective approach for enhancing information protection; however, existing optical encryption strategies are unable to reliably recover encrypted information following free-space transmission. To address this challenge, we propose a novel protocol named the optical coherence engineering encryption protocol (OCE-Encryption Protocol). By jointly manipulating the optical coherence structure and introducing astigmatic phase modulation, the protocol generates a spectral intensity ciphertext capable of secure free-space transmission. At the receiver, the original information can be accurately reconstructed by measuring the optical coherence structure of the received ciphertext and applying the correct decryption key. Furthermore, the proposed protocol demonstrates strong resilience to transmission channel disturbances. We hope that optical coherence engineering can expand the functional boundaries of existing optical encryption protocols and provide a pathway toward next-generation secure optical communication systems.

Mohammad A. Karim, Mohammed Nazrul Islam, Vijayan K. Asari

Bahram Javidi, Artur Carnicer, Masahiro Yamaguchi +25 more

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.