No abstract

<p>Este artículo presenta una alternativa para resolver la vulnerabilidad existente en los sistemas que implementan el enmascaramiento mediante la sincronización caótica, este sistema evita que los parámetros utilizados como clave de cifrado puedan ser detectados por un atacante al implementar el modelo matemático caótico del oscilador de Rössler para codificar y establecer la sincronización entre los dispositivos transmisor-receptor; además usa dos llaves de cifrado: la primera con una longitud recomendable de 2048 caracteres y la segunda se utiliza como un valor inicial. Ambas llaves se emplean para modificar continuamente uno de los parámetros del oscilador, esto fortalece la seguridad del sistema y evita que un atacante obtenga los valores del parámetro del oscilador calculando el error de sincronización promedio menor. El uso del sistema desarrollado proporciona un cifrado resistente a ataques estadísticos, además valida datos del dispositivo transmisor (nombre de usuario, password, etc.) para autorizar la transmisión hacia el destino.</p>

In this work, steganography is implemented in photographs captured by an unmanned aerial vehicle (drone), with the purpose of adding an identifier that indicates which device they are taken from so it works for the recovery of the origin. In the system, a new technique that modifies the least significant bit (LSB) is applied, using a mathematical model to generate the chaotic orbits, one of the parts selects the RGB channel (Red, Green or Blue) where the LSB is changed and the other is implemented to calculate the random position of the sub pixel to be modified in the selected channel. In addition, a comparison between the bit to be hidden and the LSB of the pixel of the image is performed to verify if it is not necessary to modify it, which lessens the alterations in the container image. It is a tool to capture photos remotely with the Ar.Drone 2.0, with the features needed to perform an analysis that uses correlation diagrams and histograms to verify if the integrity of the message is guaranteed or if changes in the stego-image are visible to the naked eye. On the other hand, a test was done on the Baboon image to compare the robustness of the proposed system with other investigations, evaluating the correlation, contrast, energy, homogeneity, MSE, PSNR and quality index. The results generated were compared with the work of other authors concluding our system provides greater security, integrity, high sensitivity to the keys, it is not linked to a single chaotic system and can be applied to hide imperceptibly all kinds of information, in: radiographs, videos, files, official documents, and other types of containers.

In this article, a safe communication system is proposed that implements one or more portable devices denominated SBC (single-board computers), with which photographs are taken and that later utilizes the OpenCV Library for the detection and identification of the faces that appear in them. Subsequently, it consults the information in a stored database, whether locally in SBC or in a remote server, to verify that the faces should be coded, and it encrypts these, implementing a new cryptosystem that executes mathematical models to generate chaotic orbits, one of which is used for application on two occasions the technique of diffusion with the purpose of carrying out a small change in one of the pixels of the image, generating very different cryptograms. In addition, in order to make a safer system, it implements other chaotic orbits during the technique of confusion. With the purpose of verifying the robustness of the encryption algorithm, a statistical analysis is performed employing histograms, horizontal, vertical, and diagonal correlation diagrams, entropy, number of pixel change rate (NPCR), unified average change intensity (UACI), sensitivity of the key, encryption quality analysis, and the avalanche effect. The cryptosystem is very robust in that it generates highly disordered cryptograms, supports differential attacks, and in addition is highly sensitive to changes in the pixels as well as in the encrypted keys.