Nominal C-Unification

Nominal unification is an extension of first-order unification that takes into account the \alpha-equivalence relation generated by binding operators, following the nominal approach. We propose a sound and complete procedure for nominal unification with commutative operators, or nominal C-unification for short, which has been formalised in Coq. The procedure transforms nominal C-unification problems into simpler (finite families) of fixpoint problems, whose solutions can be generated by algebraic techniques on combinatorics of permutations.Comment: Pre-proceedings paper presented at the 27th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2017), Namur, Belgium, 10-12 October 2017 (arXiv:1708.07854

Statistical Complexity Analysis of Turing Machine tapes with Fixed Algorithmic Complexity Using the Best-Order Markov Model

Sources that generate symbolic sequences with algorithmic nature may differ in statistical complexity because they create structures that follow algorithmic schemes, rather than generating symbols from a probabilistic function assuming independence. In the case of Turing machines, this means that machines with the same algorithmic complexity can create tapes with different statistical complexity. In this paper, we use a compression-based approach to measure global and local statistical complexity of specific Turing machine tapes with the same number of states and alphabet. Both measures are estimated using the best-order Markov model. For the global measure, we use the Normalized Compression (NC), while, for the local measures, we define and use normal and dynamic complexity profiles to quantify and localize lower and higher regions of statistical complexity. We assessed the validity of our methodology on synthetic and real genomic data showing that it is tolerant to increasing rates of editions and block permutations. Regarding the analysis of the tapes, we localize patterns of higher statistical complexity in two regions, for a different number of machine states. We show that these patterns are generated by a decrease of the tape's amplitude, given the setting of small rule cycles. Additionally, we performed a comparison with a measure that uses both algorithmic and statistical approaches (BDM) for analysis of the tapes. Naturally, BDM is efficient given the algorithmic nature of the tapes. However, for a higher number of states, BDM is progressively approximated by our methodology. Finally, we provide a simple algorithm to increase the statistical complexity of a Turing machine tape while retaining the same algorithmic complexity. We supply a publicly available implementation of the algorithm in C++ language under the GPLv3 license. All results can be reproduced in full with scripts provided at the repository.Peer reviewe

A Secure Real-time Multimedia Streaming through Robust and Lightweight AES Encryption in UAV Networks for Operational Scenarios in Military Domain

multimodal data encryption and decryption for security applications in protected environments like espionage, situational awareness, monitoring, and counter-UAV. Data is captured from drones equipped with microphone arrays and cameras. This is performed by exploiting acoustic event analysis, video tracking, and recognition, performed on a ground station. All the communications are delivered in a secure data channel. Integrity and secrecy of the sensitive data acquired by drones must be guaranteed until the data is delivered in real-time from UAVs to the destination node. A possible data exploit may cause critical problems if the data is intercepted by malicious attackers. Being the drones equipped with low energy consuming devices with low computational power, like single-board-computers, a real-time lightweight application-level AES encryption, in addition to the MAC encryption of the wireless communication channel, has been considered. In the experiment, the encryption and decryption process has been optimized, even under adverse transmission conditions ensuring continuous data encryption even if some packets are lost or the connection is repeatedly dropped and reestablished

A Review of Various Security Techniques in Cloud computing

Cloud computing is the major area of research. In this paper our aim is to study the existing literature of various security algorithms in cloud computing. So, Security is an important factor in cloud computing for ensuring clients data is placed on the secure mode in the cloud. Data must not be stolen by the third party so authentication of client becomes a mandatory task. In this paper, we discuss a number of existing techniques used to provide security in the field of cloud computing on the basis of different parameters

IMPLEMENTATION OF PIPELINED DES USING VERILOG

An implementation of the Data Encryption Standard (DES) algorithm is described. Protection of data during transmission or while in storage may be necessary to maintain the confidentiality and integrity of the information represented by the data. The algorithms uniquely define the mathematical steps required to transform data into a cryptographic cipher and also to transform the cipher back to the original form. The proposed pipeline method is for improving the speed of execution when compare with the non-pipeline method

Memory-Based High-Level Synthesis Optimizations Security Exploration on the Power Side-Channel

High-level synthesis (HLS) allows hardware designers to think algorithmically and not worry about low-level, cycle-by-cycle details. This provides the ability to quickly explore the architectural design space and tradeoffs between resource utilization and performance. Unfortunately, security evaluation is not a standard part of the HLS design flow. In this article, we aim to understand the effects of memory-based HLS optimizations on power side-channel leakage. We use Xilinx Vivado HLS to develop different cryptographic cores, implement them on a Spartan-6 FPGA, and collect power traces. We evaluate the designs with respect to resource utilization, performance, and information leakage through power consumption. We have two important observations and contributions. First, the choice of resource optimization directive results in different levels of side-channel vulnerabilities. Second, the partitioning optimization directive can greatly compromise the hardware cryptographic system through power side-channel leakage due to the deployment of memory control logic. We describe an evaluation procedure for power side-channel leakage and use it to make best-effort recommendations about how to design more secure architectures in the cryptographic domain

Attacking AES-Masking Encryption Device with Correlation Power Analysis

Modern communication system use cryptography algorithm to ensure data still confidentiality, integrity, and authentic. There is a new vulnerability in a cryptographic algorithm when implemented on a hardware device. This vulnerability is considered capable of uncovering a secret key used in a cryptographic algorithm. This technique is known as a power analysis attack. Previous and other research introduces countermeasure to countering this new vulnerability. Some researchers suggest using logic level with encoding the AES. The countermeasure using logic is meager cost and efficient. The contribution of this paper is to analyze CPA on encryption device that has been given logic level countermeasure. Our finding of this paper is the use of encoding with one-hot masking technique does not provide the maximum countermeasure effect against CPA-based attacks. In this research, CPA attack can be successfully revealing the AES secret-ke

Enhancing the Performance of the Advanced Encryption Standard (AES) Algorithm Using Multiple Substitution Boxes

This paper proposes for a modified version of the AES algorithm using multiple substitution boxes (S-Boxes).  While many studies have been conducted specifically on modifying the S-Box, these studies were made to replace the Rijndael S-boxes in the AES cipher.  We propose to implement two substitution boxes, where the first S-Box is the Rijndael S-box and will be used as is.  The second S-Box was constructed through an XOR operation and affine transformation and will replace the MixColumns operation within the internal rounds in the cipher.  Based on simulation testing conducted, it was found out that there is a significant difference in the speed performance between the two versions favouring the proposed AES algorithm using multiple S-Box.  The findings also revealed that in both encryption and decryption processes, the AES-2SBox performed more efficiently at 27.638% and 108.369% respectively as compared to the original AES algorithm.  However, when tested using the avalanche effect, the changes in the output bits were below the minimum expected rate