Institute of Electron Technology
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Faster Point Scalar Multiplication on Short Weierstrass Elliptic Curves over Fp using Twisted Hessian Curves over Fp2, Journal of Telecommunications and Information Technology, 2016, nr 3
Get PDFThis article shows how to use fast Fp2 arithmetic and twisted Hessian curves to obtain faster point scalar multiplication on elliptic curve ESW in short Weierstrass form over Fp. It is assumed that p and #ESW(Fp) are different large primes, #E(Fq) denotes number of points on curve E over field Fq and #Et SW (Fp) Fp), where Et is twist of E, is divisible by 3. For example this method is suitable for two NIST curves over Fp: NIST P-224 and NIST P-256. The presented solution may be much faster than classic approach. Presented solution should also be resistant for side channel attacks and information about Y coordinate should not be lost (using for example Brier-Joye ladder such information may be lost). If coefficient A in equation of curve ESW : y2 =x3+Ax+B in short Weierstrass curve is not of special form, presented solution is up to 30% faster than classic approach. If A=−3, proposed method may be up to 24% faster
Study of No-Reference Video Quality Metrics for HEVC Compression, Journal of Telecommunications and Information Technology, 2016, nr 1
Get PDFThe paper proposes a No-Reference (NR) quality assessment measurement originally developed for H.264, used for High Efficiency Video Coding (HEVC). In particular, authors present an investigation of NR metrics to objectively estimate the perceptual quality of a set of processed video sequences. The authors take into account typical distortions introduced by the block-based coding approaches like HEVC codec. The underlying processing used for the quality assessment considers the blockiness caused by the boundaries of each coded block and the blurring as a lack of spatial details. The correlation between the NR quality metrics and the well-known and most widely used objective metric, the Video Quality Model (VQM), is performed to validate the quality prediction accuracy based on the provided scores. The Pearson correlation coefficients obtained stand for promising results for different types of videos
L-SCANN: Logarithmic Subcentroid and Nearest Neighbor , Journal of Telecommunications and Information Technology, 2016, nr 4
Get PDFSecuring a computer network has become a need in this digital era. One way to ensure the security is by deploying an intrusion detection system (IDS), which some of them employs machine learning methods, such as k k k-nearest neighbor. Despite its strength for detecting intrusion, there are some factors, which should be improved. In IDS, some research has been done in terms of feature generation or feature selection. However, its performance may not be good enough. In this paper, a method to increase the quality of the generated features while maintaining its high accuracy and low computational time is proposed. This is done by reducing the search space in training data. In this case, the authors use distance between the evaluated point and the centroid of the other clusters, as well as the logarithmic distance between the evaluated point and the subcentroid of the respective cluster. Besides the performance, the effect of homogeneity in extracting centroid and subcentroid on the accuracy of the detection model is also evaluated. Based on conducted experiment, authors find that the proposed method is able to decrease processing time and increase the performance. In more details, by using NSL-KDD 20% dataset, there is an increase of 4%, 2%, and 6% from those of TANN in terms of accuracy, sensitivity and specificity, respectively. Similarly, by using Kyoto 2006 dataset, proposed method rises 1%, 3%, and 2% than those of TANN
Long-term Absolute Wavelength Stability of Acetylene-stabilized Reference Laser at 1533 nm , Journal of Telecommunications and Information Technology, 2016, nr 4
Get PDFThe second harmonic generation process in Periodically Poled Lithium Niobate (PPLN) has been applied in order to measure frequency of reference laser locked to acetylene absorption peak 12 12 12C2 2 2H2 2 2 (P13) (1533 nm) against optical frequency synthesizer. The measurement results have been compared to the results obtained using different techniques for the same reference laser during the past 10 years in other laboratories
Support Vector Machine based Decoding Algorithm for BCH Codes, Journal of Telecommunications and Information Technology, 2016, nr 2
Get PDFModern communication systems require robust, adaptable and high performance decoders for efficient data transmission. Support Vector Machine (SVM) is a margin based classification and regression technique. In this paper, decoding of Bose Chaudhuri Hocquenghem codes has been approached as a multi-class classification problem using SVM. In conventional decoding algorithms, the procedure for decoding is usually fixed irrespective of the SNR environment in which the transmission takes place, but SVM being a machinelearning algorithm is adaptable to the communication environment. Since the construction of SVM decoder model uses the training data set, application specific decoders can be designed by choosing the training size efficiently. With the soft margin width in SVM being controlled by an equation, which has been formulated as a quadratic programming problem, there are no local minima issues in SVM and is robust to outliers
On Radio-Frequency Spectrum Management, Journal of Telecommunications and Information Technology, 2016, nr 3
Get PDFThis article review lessons learned from the uses of radio-frequency (RF) spectrum at national and international scales. Its main purpose is to stimulate debate on how to allow new wireless systems to operate, and to reduce the chronic apparent shortage of RF spectrum. The article aims at a better understanding of the mechanisms behind spectrum management and their pertinence to the public interest. The main contributions if the article are:• Considering RF spectrum management as a construct that structures radio services and, at the same time, distributes wealth and power;• Highlighting major doctrines of RF spectrum management;• Promoting spectrum management directly by its users;• Promoting cooperation and transparency.The several parts of the paper include the evolution of spectrum exploitation, and a foreseeable future by taking a closer look at major dilemmas and challenges. The paper ends with general comments and conclusions
Variable-Weight Optical Code Division Multiple Access System using Di erent Detection Scheme, Journal of Telecommunications and Information Technology, 2016, nr 3
Get PDFIn this paper a Variable Weight OCDMA (VW-OCDMA) system using KS code with Direct Decoding (DD), Complementary Subtraction (CS) and AND subtraction detections is proposed. System performance is analyzed using mathematical approximation and software simulation. In mathematical analysis, the e ects of Phase-Induced Intensity Noise, shot noise and thermal noise are taken into account. Bit Error Rate of di erent users is plotted as a function of received optical power per chip with varying the bit rates and number of active users. It has been shown that for di erent bit rates and number of users, system using DD has better performance than the system applying CS and AND detection. Using DD scheme, the number of active users are 100 while this value is 27 and 25 in case of using CS and AND detection, respectively, when the received optical power per chip is {10 dBm
Concept for a Measurement Management System for Access Service to the Internet, Journal of Telecommunications and Information Technology, 2016, nr 3
Get PDFThis paper describes the problems associated with the provision of quality of service over an access connection to the Internet, i.e. the Internet Access Service (IAS). The paper has something of an overview character. Following a comprehensive introduction to the subject of “Changing Network Technologies” the paper focuses on the topic “Quality of IAS” in the light of regulatory directives of the European Parliament and the latest recommendations of ITU-T and ETSI. The focus will then shift to “Measurement Points and Measurement Scenarios for Determining QoS”. This topic will be described in detail and illustrated with several graphics. The final chapter has a pronounced scientific character and contains, among other things, a suggestion for a so-called Measurement Management System (MMS) to aid the design, execution and evaluation of efficient, automatic QoS measurements in networks
Server Workload Model Identification: Monitoring and Control Tools for Linux, Journal of Telecommunications and Information Technology, 2016, nr 2
Get PDFServer power control in data centers is a coordinated process carefully designed to reach multiple data center management objectives. The main objectives include avoiding power capacity overloads and system overheating, as well as fulfilling service-level agreements (SLAs). In addition to the primary goals, server control process aims to maximize various energy efficiency metrics subject to reliability constraints. Monitoring of data center performance is fundamental for its efficient management. In order to keep track of how well the computing tasks are processed, cluster control systems need to collect accurate measurements of activities of cluster components. This paper presents a brief overview of performance and power consumption monitoring tools available in the Linux systems