2019. 3rd Issue
Volume XI, Number 3
Full issue (7,5 MB)
MESSAGE FROM THE EDITOR-IN-CHIEF
Indexing current advances with DOI – at the Infocommunications Journal
The vast domain of Infocommunications reach from the physics of wireless and wired communication channels, through traversing the information – in a secure way – to its destination(s) to analyzing the characteristics of that transmission.
Since the area is huge, categorizing advances is hard. We operate with keywords – index terms –, text-mining of research papers, and creating clusters based on similar set of areas involved in these papers. The survey papers that keep appearing in our journal is useful in this sense as well: connecting and summarizing the current knowledge of a field – even if it has just emerged. In order to help indexing of our journal papers and the ones cited inside, we encourage our authors to reference the DOI – Document Object Identifier – of their cited articles, and we make sure these DOIs point to the source of the document, making it easier for the readers to reach it directly. This activity is animated by DOI commissioners such as the Hungarian Academy of Sciences, who helps us assigning DOIs through the original DOI provider, CrossRef.
INVITED SURVEY PAPER
Gábor Fodor, László Pap and Miklós Telek
Recent Advances in Acquiring Channel State Information in Cellular MIMO Systems
In cellular multi-user multiple input multiple output (MU-MIMO) systems the quality of the available channel state information (CSI) has a large impact on the system performance. Specifically, reliable CSI at the transmitter is required to determine the appropriate modulation and coding scheme, transmit power and the precoder vector, while CSI at the receiver is needed to decode the received data symbols. Therefore, cellular MUMIMO systems employ predefined pilot sequences and configure associated time, frequency, code and power resources to facilitate the acquisition of high quality CSI for data transmission and reception. Although the trade-off between the resources used user data transmission has been known for long, the near-optimal configuration of the vailable system resources for pilot and data transmission is a topic of current research efforts. Indeed, since the fifth generation of cellular systems utilizes heterogeneous networks in which base stations are equipped with a large number of transmit and receive antennas, the appropriate configuration of pilot-data resources becomes a critical design aspect. In this article, we review recent advances in system design approaches that are designed for the acquisition of CSI and discuss some of the recent results that help to dimension the pilot and data resources specifically in cellular MU-MIMO systems.
PAPERS FROM OPEN CALL
Cebrail ÇiFTLiKLi, Musaab AL-OBAIDI, Mohammed FADHIL and Wael AL-OBAIDI
Cooperative OSIC System to Exploit the Leakage Power of MU-MIMO Beamforming based on Maximum SLR for 5G
This study investigated the crucial—but not welldiscussed—issues involved in designing beamforming for all receivers, subject to leakage power constraints. Our assumption is that all users use ordered successive interference cancellation (OSIC) detection when the channel state information (CSI) is available. The problem of interest is to find beamforming that can improve OSIC performance of a multi-user scheme without significantly increasing the complexity. This study considers the transceiver design for multi-user MIMO (MU-MIMO) communications, in which a single transmitter adopts beamforming to simultaneously transmit information at first time-slot. During the second time-slot, receivers cooperate to share specific results of OSIC detection in each user. We propose the maximum-likelihood (ML) to estimate the received symbols.The estimated symbols will be used in OSIC detection to detect interference symbols. Promising results show that our cooperative OSIC scheme of the MU-MIMO beamforming system based on maximum signal-to-leakage ratio (SLR) realizes the diversity order of OSIC. Also, by utilizing leakage power as a useful power and not just as an interference power, the performance of the proposed scheme over Rayleigh and Rician channels is significantly better than the performance of classical MU-MIMO beamforming system based on SLR at a high signalto-noise ratio (SNR).
Roman N. Ipanov
Polyphase Radar Signals with ZACZ Based on p-Pairs D-Code Sequences and Their Compression Algorithm
In modern synthetic-aperture radars, signals with the linear frequency modulation (LFM) have found the practical application as probing signals. Utilization of LFM-signals was formed historically since they were the first wideband signals, which found application in radar technology, and their properties have studied a long time ago and in detail. However, the LFM-signals have the “splay” ambiguity function, which results the ambiguity in range. The question of the probing signal choice is also relevant in connection with the problem of weak echoes detection, which are closed by the side lobes of ACF of the strong echoes. In this paper, the polyphase (p-phase, where p is the prime integer number) radar signal, which has an area of zero side lobes in a vicinity of the central peak of autocorrelation function, has been synthesized. It is shown that this signal represents a train from p coherent phase-code-shift keyed pulses, which are coded by complementary sequences of the p-ary D-code. The method of ensemble set formation of the p-ary D-code for signal synthesis is suggested. Correlation characteristics of the synthesized signal are discussed. The compression algorithm of this signal is considered including in its structure the combined algorithm of Vilenkin-Chrestenson and Fourier fast transform.
Dmitrii I. Popov and Sergey M. Smolskiy
Synthesis and Analysis Non-recursive Rejection Filters Transient Mode
The non-recursive rejection filter (RF), which is improved with the purpose of transient acceleration at arriving of the passive interference edge caused by disturbing reflections from fixed or slow-moving objects, is synthesized by the state-variables method. The structural diagram is offered of the tunable RF in the transient with the purpose of improvement of signal extraction effectiveness from moving targets on the background of the passive interference edge. The comparative analysis is performed of RF effectiveness for fixed and tunable structure in the transient according to the criterion of the normalized interference suppression coefficient and the improvement coefficient of the signal-to-interference ratio. The essential increase of the signal extraction effectiveness from the moving objects on the background on the interference edge for the wide class of the spectral-correlation characteristics at RF structure modification.
Aymen Hasan Alawadi, Maiass Zaher and Sándor Molnár
Methods for Predicting Behavior of Elephant Flows in Data Center Networks
Several Traffic Engineering (TE) techniques based on SDN (Software-defined networking) proposed to resolve flow competitions for network resources. However, there is no comprehensive study on the probability distribution of their throughput. Moreover, there is no study on predicting the future of elephant flows. To address these issues, we propose a new stochastic performance evaluation model to estimate the loss rate of two state-of-art flow scheduling algorithms including Equalcost multi-path routing (ECMP), Hedera besides a flow congestion control algorithm which is Data Center TCP (DCTCP). Although these algorithms have theoretical and practical benefits, their effectiveness has not been statistically investigated and analyzed in conserving the elephant flows. Therefore, we conducted extensive experiments on the fat-tree data center network to examine the efficiency of the algorithms under different network circumstances based on Monte Carlo risk analysis. The results show that Hedera is still risky to be used to handle the elephant flows due to its unstable throughput achieved under stochastic network congestion. On the other hand, DCTCP found suffering under high load scenarios. These outcomes might apply to all data center applications, in particular, the applications that demand high stability and productivity.
Yuancheng Li, Guixian Wu and Xiaohan Wang
Deep Web Data Source Classification Based on Text Feature Extension and Extraction
With the growth of volume of high quality information in the Deep Web, as the key to utilize this information, Deep Web data source classification becomes one topic with great research value. In this paper, we propose a Deep Web data source classification method based on text feature extension and extraction. Firstly, because the data source contains less text, some data sources even contain less than 10 words. In order to classify the data source based on the text content, the original text must be extended. In text feature extension stage, we use the N-gram model to select extension words. Secondly, we proposed a feature extraction and classification method based on Attention-based Bi-LSTM. By combining LSTM and Attention mechanism, we can obtain contextual semantic representation and focus on words that are closer to the theme of the text, so that more accurate text vector representation can be obtained. In order to evaluate the performance of our classification model, some experiments are executed on the UIUC TEL-8 dataset. The experimental result shows that Deep Web data source classification method based on text feature extension and extraction has certain promotion in performance than some existing methods.
CALL FOR PAPERS
IEEE 20th Mediterranean Electrotechnical Conference
IEEE MELECON 2020, Palermo, Italy
International Federation for Information Processing Networking 2020
IFIP Networking 2020, Paris, France
2019. 2nd Issue
Full issue (11,7MB)
MESSAGE FROM THE EDITOR-IN-CHIEF
Impactful Surveys for the 70th Anniversary of HTE
The impact of a scientific achievement is hard to measure, especially in the short run. Still, human lifespan is relatively short when compared to the wide spread applications of theoretical breakthroughs – so we define ”factors” predicting the possible impact of new ideas and contributions.
INVITED SURVEY PAPERS
Dorottya Papp, Kristóf Tamás and Levente Buttyán
IoT Hacking – A Primer
The Internet of Things (IoT) enables many new and exciting applications, but it also creates a number of new risks related to information security. Several recent attacks on IoT devices and systems illustrate that they are notoriously insecure. It has also been shown that a major part of the attacks resulted in full adversarial control over IoT devices, and the reason for this is that IoT devices themselves are weakly protected and they often cannot resist even the most basic attacks. Penetration testing or ethical hacking of IoT devices can help discovering and fixing their vulnerabilities that, if exploited, can result in highly undesirable conditions, including damage of expensive physical equipment or even loss of human life. In this paper, we give a basic introduction into hacking IoT devices. We give an overview on the methods and tools for hardware hacking, firmware extraction and unpacking, and performing basic firmware analysis. We also provide a survey on recent research on more advanced firmware analysis methods, including static and dynamic analysis of binaries, taint analysis, fuzzing, and symbolic execution techniques. By giving an overview on both practical methods and readily available tools as well as current scientific research efforts, our work can be useful for both practitioners and academic researchers.
Laszlo Gyongyosi, Laszlo Bacsardi and Sandor Imre
A Survey on Quantum Key Distribution
Quantum key distribution (QKD) protocols represent an important practical application of quantum information theory. QKD schemes enable legal parties to establish unconditionally secret communication by exploiting the fundamental attributes of quantum mechanics. Here we present an overview of QKD rotocols. We review the principles of QKD systems, the implementation basis, and the application of QKD protocols in the standard Internet and the quantum Internet.
Visible Light Communication Survey
Communication applying visible light technology is a novel approach. Visible Light Communication (VLC) development is motivated by the increasing demand for wireless communication technologies. It has the potential to provide highspeed data communication with good security and improved energy efficiency. The rapid evolution of VLC was sustained by the LEDs performances. The Light-Emitting-Diode (LED) luminaires are capable of switching to the different light intensity at a fast rate. This function can be used for data transmission. This article focuses on the physical layer of the VLC links. It reviews the technology, the topology of the proposed connection, and the benefits of this approach. The main research trends are identified emphasizing state of the art in this area. It shows how VLC technology evolved and what are the performances achieved at this time. Various structures of the transmitter and receiver are studied, and different modulation schemes are investigated. Finally, numerous applications of VLC technology are presented.
PAPERS FROM OPEN CALL
Sándor Rácz, Géza Szabó and József Pető
Performance Evaluation of Closed-loop Industrial Applications Over Imperfect Networks
5G networks provide technology enablers targeting industrial applications. One key enabler is the Ultra Reliable Low Latency Communication (URLLC). This paper studies the performance impact of network delay on closed-loop control for industrial applications. We investigate the performance of the closed-loop control of an UR5 industrial robot arm assuming fix delay. The goal is to stress the system at the upper limit of the possible network delay. We prove that to achieve the maximum speed, URLLC is a must have.
Zoltán Jakó, Ádám Knapp and Nadim El Sayed
Wireless Authentication Solution and TTCN-3 based Test Framework for ISO-15118 Wireless V2G Communication
Vehicle to grid (V2G) communication for electric vehicles and their charging points is already well established by the ISO 15118 standard. The standard allows vehicles to communicate with the charging station using the power cable, i.e. a wired link, but it is improved to enable wireless (WLAN) links as well. This paper aims to provide an implementation accomplishes a wireless authentication solution (WAS). With that the electric vehicles can establish V2G connection when approaching the charging pool, then identify and authenticate the driver and/or the vehicle. Furthermore, the paper presents a TTCN-3 based validation and verification (V&V) framework in order to test the conformance of the prototype implementation against the standard.
Gazi Zahirul Islam and Mohammod Abul Kashem
An OFDMA-based Hybrid MAC Protocol for IEEE 802.11ax
Two types of MAC mechanisms i.e., random access and reservation could be adopted for OFDMA-based wireless LANs. Reservation-based MAC is more appropriate than random access MAC for connection-oriented applications as connectionoriented applications provide strict requirements of traffic demands. On the other hand, random access mechanism is a preferred choice for bursty traffic i.e., data packets which have no fixed pattern and rate. As OFDMA-based wireless networks promise to support heterogeneous applications, researchers assume that applications with and without traffic specifications will coexist. Eventually, OFDMA-based wireless LAN will deploy hybrid MAC mechanisms inheriting traits from random access and reservation. In this article, we design a new MAC protocol which employs one kind of hybrid mechanism that will provide high throughput of data as well as maintains improved fair access policy to the medium among the terminals. The protocol works in two steps, where at step 1 sub-channels are approximately evenly distributed to the terminals and at step 2 terminals within in a subchannel will contend for medium randomly if the total number of terminals of the system is larger than the number of sub-channels. The details of the protocol is illustrated in the paper and we analyze the performance of our OFDMA-based multi-channel hybrid protocol using comprehensive computer simulations. Simulation results validate that our proposed protocol is more robust than the conventional CSMA/CA protocol in terms of throughput, collision reduction and fair access. In addition, the theoretical analysis of the saturation throughput of the protocol is also evaluated using an existing comprehensive model.
Máté Nagy, János Tapolcai and Gábor Rétvári
R3D3: A Doubly Opportunistic Data Structure for Compressing and Indexing Massive Data
Opportunistic data structures are used extensively in big data practice to break down the massive storage space requirements of processing large volumes of information. A data structure is called (singly) opportunistic if it takes advantage of the redundancy in the input in order to store it in iformationtheoretically minimum space. Yet, efficient data processing requires a separate index alongside the data, whose size often substantially exceeds that of the compressed information. In this paper, we introduce doubly opportunistic data structures to not only attain best possible compression on the input data but also on the index. We present R3D3 that encodes a bitvector of length n and Shannon entropy H0 to nH0 bits and the accompanying index to nH0(1/2 + O(log C/C)) bits, thus attaining provably minimum space (up to small error terms) on both the data and the index, and supports a rich set of queries to arbitrary position in the compressed bitvector in O(C) time when C = o(log n). Our R3D3 prototype attains several times space reduction beyond known compression techniques on a wide range of synthetic and real data sets, while it supports operations on the compressed data at comparable speed.
CALL FOR PAPERS
IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS
ICC 2020, Dublin, Ireland