Institute of Electron Technology
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An Inclusive Performance Analysis of Single-branch Single-relay AF Transmission in a Mixed Rayleigh-Nakagami-m Fading Environment, Journal of Telecommunications and Information Technology, 2019, nr 3
Full text linkIn this paper, the end-to-end performance of a single-branch two-hop amplify-and-forward (AF) relaying network in a mixed Rayleigh-Nakagami-m fading environment, is investigated. Four different fading scenarios and three standard relay configurations for each scenario are considered. Exact analytical expressions for the outage probability and tight upper bounds for the ergodic capacity are derived. Results of Monte Carlo simulations are provided to verify the accuracy of the analytical results
A Modified Approach to Punctured Product Polar Codes, Journal of Telecommunications and Information Technology, 2019, nr 3
Full text linkA high-performance polar code introduced as a product polar code can be constructed by concatenating two short length polar codes. The punctured structure of this code was achieved by puncturing one of its constituent codes. The constructed polar code provided better performance than a single polar code in the error floor region. However, its performance in the waterfall region was not as good as that of single polar codes. This paper proposes a new puncturing algorithm for product codes constructed by two identical polar codes. Puncturing is conducted on both constituent codes, to ensure that the new code outperforms the previously punctured product polar and single polar codes. This is evident in both waterfall and error floor regions
Spline-Extrapolation Method in Traffic Forecasting in 5G Networks, Journal of Telecommunications and Information Technology, 2019, nr 3
Full text linkThis paper considers the problem of predicting self-similar traffic with a significant number of pulsations and the property of long-term dependence, using various spline functions. The research work focused on the process of modeling self-similar traffic handled in a mobile network. A splineextrapolation method based on various spline functions (linear, cubic and cubic B-splines) is proposed to predict selfsimilar traffic outside the period of time in which packet data transmission occurs. Extrapolation of traffic for short- and long-term forecasts is considered. Comparison of the results of the prediction of self-similar traffic using various spline functions has shown that the accuracy of the forecast can be improved through the use of cubic B-splines. The results allow to conclude that it is advisable to use spline extrapolation in predicting self-similar traffic, thereby recommending this method for use in practice in solving traffic prediction-related problems
Methods of Classification of the Genera and Species of Bacteria Using Decision Tree, Journal of Telecommunications and Information Technology, 2019, nr 4
Full text linkThis paper presents a computer-based method for recognizing digital images of bacterial cells. It covers automatic recognition of twenty genera and species of bacteria chosen by the author whose original contribution to the work consisted in the decision to conduct the process of recognizing bacteria using the simultaneous analysis of the following physical features of bacterial cells: color, size, shape, number of clusters, cluster shape, as well as density and distribution of the cells. The proposed method may be also used to recognize the microorganisms other than bacteria. In addition, it does not require the use of any specialized equipment. The lack of demand for high infrastructural standards and complementarity with the hardware and software widens the scope of the method’s application in diagnostics, including microbiological diagnostics. The proposed method may be used to identify new genera and species of bacteria, but also other microorganisms that exhibit similar morphological characteristic
Theoretical and Experimental Analysis of Cryptographic Hash Functions, Journal of Telecommunications and Information Technology, 2019, nr 1
Full text linkThe paper presents a theoretical introduction to the cryptographic hash function theory and a statistical experimental analysis of selected hash functions. The definition of hash functions, differences between them, their strengths and weaknesses are explained as well. Different hash function types, classes and parameters are described. The features of hash functions are analyzed by performing statistical analysis. Experimental analysis is performed for three certified hash functions: SHA1-160, SHA2-512 and SHA3-512. Such an analysis helps understand the behavior of cryptographic hash functions and may be very helpful for comparing the security level of the hashing method selected. The tests may serve as a basis for examination of each newly proposed hash function. Additionally, the analysis may be harness as a method for comparing future proposals with the existing functions
A Novel Graph-modification Technique for User Privacy-preserving on Social Networks, Journal of Telecommunications and Information Technology, 2019, nr 3
Full text linkThe growing popularity of social networks and the increasing need for publishing related data mean that protection of privacy becomes an important and challenging problem in social networks. This paper describes the (k,l k,l k,l)-anonymity model used for social network graph anonymization. The method is based on edge addition and is utility-aware, i.e. it is designed to generate a graph that is similar to the original one. Different strategies are evaluated to this end and the results are compared based on common utility metrics. The outputs confirm that the na¨ıve idea of adding some random or even minimum number of possible edges does not always produce useful anonymized social network graphs, thus creating some interesting alternatives for graph anonymization techniques
Multifactor Authentication and Key Management Protocol for WSN-assisted IoT Communication, Journal of Telecommunications and Information Technology, 2019, nr 3
Full text linkIn this paper a novel multi-factor authentication protocol for IoT applications, relying on enhanced Rabinassisted elliptic curve cryptography, biometric features and time stamping methods, is developed. Furthermore, a fuzzy verification algorithm has been developed to perform receiverlevel user verification, making computation efficient in terms of computational overhead as well as latency. An NS2 simulation-based performance assessment has revealed that the multifactor authentication and key management models we have proposed are capable of not only avoiding security breaches, such as smart card loss (SCLA) and impersonation attacks, but can also ensure the provision of maximum possible QoS levels by offering higher packet delivery and minimum latency rates
Robot Local Network Using TQS Protocol for Land-to-Underwater Communications, Journal of Telecommunications and Information Technology, 2019, nr 1
Full text linkThis paper presents a model and an analysis of the Tag QoS switching (TQS) protocol proposed for heterogeneous robots operating in different environments. Collaborative control is topic that is widely discussed in multirobot task allocation (MRTA) – an area which includes establishing network communication between each of the connected robots. Therefore, this research focuses on classifying, prioritizing and analyzing performance of the robot local network (RLN) model which comprises a point-to-point topology network between robot peers (nodes) in the air, on land, and under water. The proposed TQS protocol was inspired by multiprotocol label switching (MPLS), achieving a quality of service (QoS) where swapping and labeling operations involving the data packet header were applied. The OMNET++ discrete event simulator was used to analyze the percentage of losses, average access delay, and throughput of the transmitted data in different classes of service (CoS), in a line of transmission between underwater and land environments. The results show that inferior data transmission performance has the lowest priority with low bitrates and extremely high data packet loss rates when the network traffic was busy. On the other hand, simulation results for the highest CoS data forwarding show that its performance was not affected by different data transmission rates characterizing different mediums and environments
Adaptive Load Balancing Ad Hoc Routing Scheme Inspired by True Slime Mold, Journal of Telecommunications and Information Technology, 2019, nr 1
Full text linkEngineering neo-biomimetics, i.e. imitation models based on body structures and behavior of living organisms, relied upon to solve complex problems, have been studied in various fields. In distributed networks, such as ad-hoc networks and wireless sensor networks, the behavior of a variety of true slime molds which are capable of constructing multipath flow networks based on the amount of body, has been studied. Ad hoc networks only consist of mobile terminals (nodes) that can relay packets along an established route. However, link relations and the available bandwidth of the nodes change dynamically due to the mobility of nodes. In addition, the speed of communication between nodes also varies due to node positions and their communication-related quality. Thus, practical use of ad-hoc networks still remains an issue, because it is difficult to establish stable routes under such environments. This study aims to propose an adaptive load balancing routing technique that adaptively diversifies the transmission paths based on the available bandwidth, residual battery life, and the data transmission volume, by applying a mathematical model of slime mold routing, known as the physarum solver. We confirm the effectiveness of its adaptive behavior in dynamic environments using computer simulations