Cryptographic salting for security enhancement of double random phase encryption schemes

Security in optical encryption techniques is a subject of great importance, especially in light of recent reports of successful attacks. We propose a new procedure to reinforce the ciphertexts generated in double random phase encrypting experimental setups. This ciphertext is protected by multiplexing with a 'salt' ciphertext coded with the same setup. We present an experimental implementation of the 'salting' technique. Thereafter, we analyze the resistance of the 'salted' ciphertext under some of the commonly known attacks reported in the literature, demonstrating the validity of our proposal.Fil: Velez Zea, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; ArgentinaFil: Barrera Ramírez, John Fredy. Universidad de Antioquia; ColombiaFil: Torroba, Roberto Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; Argentina. Universidad Nacional de la Plata. Facultad de Ingeniería. Uidet Grupo de Ensayos Mecanicos Aplicados.; Argentin

Experimental scrambling and noise reduction applied to the optical encryption of QR codes

In this contribution, we implement two techniques to reinforce optical encryption, which we restrict in particular to the QR codes, but could be applied in a general encoding situation. To our knowledge, we present the first experimental-positional optical scrambling merged with an optical encryption procedure. The inclusion of an experimental scrambling technique in an optical encryption protocol, in particular dealing with a QR code “container”, adds more protection to the encoding proposal. Additionally, a nonlinear normalization technique is applied to reduce the noise over the recovered images besides increasing the security against attacks. The opto-digital techniques employ an interferometric arrangement and a joint transform correlator encrypting architecture. The experimental results demonstrate the capability of the methods to accomplish the task.Fil: Barrera, John Fredy. Universidad de Antioquia; ColombiaFil: Vélez, Alejandro. Universidad de Antioquia; ColombiaFil: Torroba, Roberto Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones Opticas (i); Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentin

Optical encryption and QR codes: Secure and noise-free information retrieval

We introduce for the first time the concept of an information “container” before a standard optical encrypting procedure. The “container” selected is a QR code which offers the main advantage of being tolerant to pollutant speckle noise. Besides, the QR code can be read by smartphones, a massively used device. Additionally, QR code includes another secure step to the encrypting benefits the optical methods provide. The QR is generated by means of worldwide free available software. The concept development probes that speckle noise polluting the outcomes of normal optical encrypting procedures can be avoided, then making more attractive the adoption of these techniques. Actual smartphone collected results are shown to validate our proposal.Fil: Barrera, John Fredy. Universidad de Antioquia; ColombiaFil: Mira, Alejandro. Universidad de Antioquia; ColombiaFil: Torroba, Roberto Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones Opticas (i); Argentin

Experimental scrambling and noise reduction applied to the optical encryption of QR codes

In this contribution, we implement two techniques to reinforce optical encryption, which we restrict in particular to the QR codes, but could be applied in a general encoding situation. To our knowledge, we present the first experimental-positional optical scrambling merged with an optical encryption procedure. The inclusion of an experimental scrambling technique in an optical encryption protocol, in particular dealing with a QR code “container”, adds more protection to the encoding proposal. Additionally, a nonlinear normalization technique is applied to reduce the noise over the recovered images besides increasing the security against attacks. The opto-digital techniques employ an interferometric arrangement and a joint transform correlator encrypting architecture. The experimental results demonstrate the capability of the methods to accomplish the task.Centro de Investigaciones Óptica

Optical encryption and QR codes: Secure and noise-free information retrieval

We introduce for the first time the concept of an information “container” before a standard optical encrypting procedure. The “container” selected is a QR code which offers the main advantage of being tolerant to pollutant speckle noise. Besides, the QR code can be read by smartphones, a massively used device. Additionally, QR code includes another secure step to the encrypting benefits the optical methods provide. The QR is generated by means of worldwide free available software. The concept development probes that speckle noise polluting the outcomes of normal optical encrypting procedures can be avoided, then making more attractive the adoption of these techniques. Actual smartphone collected results are shown to validate our proposal.Facultad de Ingenierí

Finite object Talbot effect as a lens produced image

ABSTRACT: In this work we theoretically calculate the self-image field amplitude of a finite periodic object. It is compared with the field of the image of an unitary cell of the same object formed by a lens. The results are verified by simulations of the two processes

Cryptographic salting for security enhancement of double random phase encryption schemes

Security in optical encryption techniques is a subject of great importance, especially in light of recent reports of successful attacks. We propose a new procedure to reinforce the ciphertexts generated in double random phase encrypting experimental setups. This ciphertext is protected by multiplexing with a 'salt' ciphertext coded with the same setup. We present an experimental implementation of the 'salting' technique. Thereafter, we analyze the resistance of the 'salted' ciphertext under some of the commonly known attacks reported in the literature, demonstrating the validity of our proposal.Centro de Investigaciones ÓpticasUnidad de Investigación y Desarrollo Optim

Talbot effect for the periodical object limited by a finite aperture

ABSTRACT: The communicate presents a new interpretation of the Talbot effect for periodical objects limited by finite apertures. According to the proposed approach, a self-image of a real, finite object is a superposition of deformed images of an elementary cell. The singular elementary cell image is equivalent to that formed in a proper optical system. The theoretical description makes possible to define a structure of self-images. Particularly, the approach enables a determination of apertures' dimensions which lead to self-images of a reasonable quality in a desired region of an image plane. The theory is illustrated and verified by numerical simulations

Límites de velocidad y distancia en la transmisión de información por un enlace óptico de bajo costo con recuperación libre de ruido

ABSTRACT: In this paper we present the results of the information transmission by a conventional fiber optic network of low cost. The information to be transmitted is stored in a quick response code (QR code) and the transmission effects over the QR for different values of the bit rate and fiber length are analyzed. The simulations were performed using the software for optical devices and links VPI photonics. The implemented optical network does not use expensive optical devices such as doped fibers to amplify, dispersion compensating fibers or correction errors algorithms. The received QR code contains different kind of distortions generated by the conventional fiber optic network. The transmitted results are analyzed using the bit error rate and signal noise ratio parameters. The results showthat the original information can be recovered without any kind of distortion for considerable distances and transmission rates due to tolerance to noise that exhibit the QR codes.RESUMEN: En este trabajo se presentan los resultados de la transmisión de información por una red de fibra óptica convencional de bajo costo. La información a transmitir se almacena en un código de respuesta rápida (código QR) y se analizan los efectos que produce la transmisión sobre el código QR para diferentes valores de la tasa de bits y la longitud de la fibra. Las simulaciones se realizaron con el software para enlaces y dispositivos ópticos VPI photonics. La red óptica implementada no usa dispositivos ópticos costosos tales como fibras dopadas para amplificar, fibras compensadoras de dispersión o algoritmos de corrección de errores. El código QR recibido contiene diferentes tipos de distorsiones generadas por la red de fibra óptica convencional. Los datos transmitidos se analizan usando como parámetros la tasa de error binario y la relación señal a ruido. Los resultados muestran que la información original puede ser recuperada sin ningún tipo de distorsión para distancias y tasas de transmisión considerables, debido a tolerancia al ruido que exhiben los códigos QR

Encriptación óptica de información con recuperación libre de ruido

Los sistemas de protección de información basados en procesadores ópticos y que emplean una técnica de codificación de doble máscara aleatoria de fase permiten el manejo seguro de los datos, pero su recuperación no está libre de ruido. Si bien la seguridad del sistema es provista por el procesador óptico que habilita encriptar la información, en este trabajo se demuestra que la recuperación libre de ruido es posible mediante la inclusión de la codificación de respuesta rápida, sin alterar el proceso de protección de datos. La información que se desea proteger es previamente convertida en un código de respuesta rápida o código QR, y posteriormente el código es encriptado ópticamente. El código QR recuperado contendrá el ruido habitual producido por el uso de las máscaras aleatorias de fase y el procesamiento óptico-digital involucrado en el proceso. Finalmente, al escanear el código QR desencriptado se puede recuperar la información original completamente libre de ruido. Se incluye la descripción teórica del procesador óptico y se presentan resultados experimentales que demuestran la validez y aplicabilidad del sistema de protección.The information protection systems based on optical processors, employing a double random phase mask encryption technique, allow data securely handling, but the recovery is not noise-free. Although the system security is provided by the optical processor enabling the information encoding, we demonstrate in this contribution that noise-free recovery is indeed possible by including the quick response coding, without altering the data protection process. The information to be protected is first converted into a quick response code or QR code, and then this code is optically encrypted. The decrypted QR code exhibits the usual noise produced by the random phase masks along with the involved opto-digital processing. Finally, when scanning the decrypted QR code we recover the original information without noise. We include the theoretical description of the optical processor, as well as we show experimental results that corroborate the validity and applicability of the security system.Facultad de Ingenierí