Search results for " encryption"
showing 10 items of 38 documents
A novel policy-driven reversible anonymisation scheme for XML-based services
2015
Author's version of an article in the journal: Information Systems. Also available from the publisher at: http://dx.doi.org/10.1016/j.is.2014.05.007 This paper proposes a reversible anonymisation scheme for XML messages that supports fine-grained enforcement of XACML-based privacy policies. Reversible anonymisation means that information in XML messages is anonymised, however the information required to reverse the anonymisation is cryptographically protected in the messages. The policy can control access down to octet ranges of individual elements or attributes in XML messages. The reversible anonymisation protocol effectively implements a multi-level privacy and security based approach, s…
Homomorphic Approach to RF-Inhomogeneity Removal Based on Gabor Filter
2007
In this paper a bias correction algorithm for magnetic resonance imaging (MRI) is presented. The magnetic resonance (MR) images affected by this artifact, also called RF-inhomogeneity, exhibit irregular spatial brightness variations caused by magnetic field inhomogeneity. Here we present an original algorithm based on E2D - HUM, already proposed by some of the authors, where a modified Gabor filter is introduced in the elaboration chain to provide directional capabilities to suppress the artifact. The process of restoration doesn't care about the structure of the image and it has been applied to MR images of different parts of body like knee, abdomen, pelvis and brain. A comparison with oth…
HyperWall: A Hypervisor for Detection and Prevention of Malicious Communication
2020
Malicious programs vary widely in their functionality, from key-logging to disk encryption. However, most malicious programs communicate with their operators, thus revealing themselves to various security tools. The security tools incorporated within an operating system are vulnerable to attacks due to the large attack surface of the operating system kernel and modules. We present a kernel module that demonstrates how kernel-mode access can be used to bypass any security mechanism that is implemented in kernel-mode. External security tools, like firewalls, lack important information about the origin of the intercepted packets, thus their filtering policy is usually insufficient to prevent c…
Encriptación óptica empleando llaves Weierstrass-Mandelbrot
2013
[EN] This paper presents the generation of encryption keys using the local oscillating properties of the partial sums of Weierstrass-Mandelbrot fractal function. In this way, the security key can be replicated if the parameters used to obtain it are known. Therefore, these parameters can be sent instead of sending the key. This procedure reduces the amount of information to be sent and prevents possible interception of the key. Moreover, the key can not be affected by data loss or pollution. The effectiveness of the Weierstrass-Mandelbrot keys were demonstrated by computer simulation in a 4f optical encryption system and the double random phase encoding technique. These keys allow us to enc…
Elliptic Curve-Based Secure Multidimensional Aggregation for Smart Grid Communications
2017
In smart grid, data aggregation is considered as an essential paradigm in assessing information about current energy usage. To achieve the privacy-preserving goal, several homomorphic-based solutions have been proposed. However, these solutions either consider one-dimensional information or use costly pairing computation in order to ensure source authentication. In fact, smart grid data are likely to be multidimensional (e.g., time, purpose, and so on) for more accurate control. In addition, the aggregation node in smart grid needs to verify data that come from several smart meters in a residential area; hence, the verification must be cost-efficient. In this paper, we propose a scheme that…
Trusted Computing and DRM
2015
Trusted Computing is a special branch of computer security. One branch of computer security involves protection of systems against external attacks. In that branch we include all methods that are used by system owners against external attackers, for example Firewalls, IDS, IPS etc. In all those cases the system owner installs software that uses its own means to determine if a remote user is malicious and terminates the attack. (Such means can be very simple such as detecting signatures of attacks or very complex such as machine learning and detecting anomalies in the usage pattern of the remote user). Another branch of attacks requires protection by the system owner against internal users. …
A Logical Key Hierarchy Based approach to preserve content privacy in Decentralized Online Social Networks
2020
Distributed Online Social Networks (DOSNs) have been proposed to shift the control over user data from a unique entity, the online social network provider, to the users of the DOSN themselves. In this paper we focus on the problem of preserving the privacy of the contents shared to large groups of users. In general, content privacy is enforced by encrypting the content, having only authorized parties being able to decrypt it. When efficiency has to be taken into account, new solutions have to be devised that: i) minimize the re-encryption of the contents published in a group when the composition of the group changes; and, ii) enable a fast distribution of the cryptographic keys to all the m…
Volumetric Bias Correction
2007
This paper presents a method to suppress the bias artifact, also known as RF-inhomogeneity, in Magnetic Resonance Imaging (MRI). This artifact produces illumination variations due to magnetic field fluctuations of the device. In the latest years many works have been devoted to face this problem. In this work we present the 3D version of a new approach to bias correction, which is called Exponential Entropy Driven Homomorphic Unsharp Masking (E2D-HUM). This technique has been already presented by some of the authors for the 2D case only. The description of the whole method is detailed, and some experimental results are reported.
Fingerprint Traits and RSA Algorithm Fusion Technique
2012
The present work deals with modern computing systems security issues, focusing on biometric based asymmetric keys generation process. Conventional PKI systems are based on private/public keys generated through RSA or similar algorithms. The present solution embeds biometric information on the private/public keys generation process. In addition the corresponding private key depends on physical or behavioural biometric features and it can be generated when it is needed. Starting from fingerprint acquisition, the biometric identifier is extracted, cyphered, and stored in tamper-resistant smart card to overcome the security problems of centralized databases. Biometric information is then used f…
Roadmap on 3D integral imaging: Sensing, processing, and display
2020
This Roadmap article on three-dimensional integral imaging provides an overview of some of the research activities in the field of integral imaging. The article discusses various aspects of the field including sensing of 3D scenes, processing of captured information, and 3D display and visualization of information. The paper consists of a series of 15 sections from the experts presenting various aspects of the field on sensing, processing, displays, augmented reality, microscopy, object recognition, and other applications. Each section represents the vision of its author to describe the progress, potential, vision, and challenging issues in this field.