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Intelligent Wireless Technologies for Future Sensor Networks

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "Sensor Networks".

Deadline for manuscript submissions: closed (31 January 2021) | Viewed by 36299

Special Issue Editor


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Guest Editor
Department of Information and Communication Engineering, Sejong University, Seoul, Korea
Interests: wireless communication; sensor network; cognitive radio; tactile internet; machine learning and IoT
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Dynamically and efficiently allocating resources to meet the need for diversity in various services gives rise to intelligent wireless technologies. They enable the wireless systems to perceive and estimate the available resources and autonomously adapt to the wireless environment, and to reconfigure itself to maximize resource utilization.

As a promising machine learning, deep learning (DL) is becoming a powerful method to add intelligence to wireless networks. Cognitive technology, covering spectrum sensing, and access approaches can enhance spectrum utilization and reduce energy consumption. The perception capability and reconfigurability are essential elements for the cognitive technology and machine learning techniques provide effectiveness for adaptation in wireless communication.

This Special Issue anticipates state-of-the-art technologies for the cognitive technology and machine learning techniques for the future wireless sensor networks, covering new research results with a wide range of ingredients within the intelligent wireless technologies for future sensor networks.

Potential topics include but are not limited to the following:

  • Ultra-reliable and low-latency sensor networks
  • AI or machine learning-based intelligent sensor networks
  • Applications and protocols using optical wireless communication
  • Energy-efficient system and network design for various applications
  • Multiple access schemes considering energy consumption and delay constraints
  • Cooperative haptic sensor networks for the tactile Internet
  • Sensor network optimization using machine learning and game-theoretic approaches
  • Sensor Networks in 5G/B5G networks (URLLC and mMTC)
  • Cognitive Radio Sensor Networks
  • Security and privacy for sensor networks
  • Sensors and hardware for sensor networks
  • Resource management, edge computing, and network slicing for efficient sensor networks
  • Sensor networks for mission-critical applications
  • Other related issues.

Prof. Hyung Seok Kim
Guest Editor

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Keywords

  • Sensor networks
  • Artificial intelligence
  • Machine learning
  • Cognitive radio
  • Tactile internet
  • mMTC
  • URLLC

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Published Papers (9 papers)

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29 pages, 10348 KiB  
Article
A Spatiotemporal-Oriented Deep Ensemble Learning Model to Defend Link Flooding Attacks in IoT Network
by Yen-Hung Chen, Yuan-Cheng Lai, Pi-Tzong Jan and Ting-Yi Tsai
Sensors 2021, 21(4), 1027; https://doi.org/10.3390/s21041027 - 3 Feb 2021
Cited by 8 | Viewed by 2598
Abstract
(1) Background: Link flooding attacks (LFA) are a spatiotemporal attack pattern of distributed denial-of-service (DDoS) that arranges bots to send low-speed traffic to backbone links and paralyze servers in the target area. (2) Problem: The traditional methods to defend against LFA are heuristic [...] Read more.
(1) Background: Link flooding attacks (LFA) are a spatiotemporal attack pattern of distributed denial-of-service (DDoS) that arranges bots to send low-speed traffic to backbone links and paralyze servers in the target area. (2) Problem: The traditional methods to defend against LFA are heuristic and cannot reflect the changing characteristics of LFA over time; the AI-based methods only detect the presence of LFA without considering the spatiotemporal series attack pattern and defense suggestion. (3) Methods: This study designs a deep ensemble learning model (Stacking-based integrated Convolutional neural network–Long short term memory model, SCL) to defend against LFA: (a) combining continuous network status as an input to represent “continuous/combination attacking action” and to help CNN operation to extract features of spatiotemporal attack pattern; (b) applying LSTM to periodically review the current evolved LFA patterns and drop the obsolete ones to ensure decision accuracy and confidence; (c) stacking System Detector and LFA Mitigator module instead of only one module to couple with LFA detection and mediation at the same time. (4) Results: The simulation results show that the accuracy rate of SCL successfully blocking LFA is 92.95%, which is 60.81% higher than the traditional method. (5) Outcomes: This study demonstrates the potential and suggested development trait of deep ensemble learning on network security. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>Link flooding attacks (LFA) situation.</p>
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<p>Convolutional neural network (CNN) architecture.</p>
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<p>Long short-term memory (LSTM) architecture.</p>
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<p>System model.</p>
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<p>Architecture of CNN-LSTM (SCL).</p>
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<p>Architecture of CNN-LSTM (SCL).</p>
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<p>Architecture of System Detector module.</p>
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<p>Architecture of LFA Mitigator module.</p>
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<p>Experiment topology.</p>
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<p>Comparison of the number of convolution layers.</p>
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<p>Comparison of the number of convolution layers.</p>
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<p>FRR and FAR of three convolution layers.</p>
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<p>Comparison of the number of pooling layers.</p>
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<p>Comparison of different orders of pooling in CNN.</p>
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<p>Comparison of different activation functions in CNN.</p>
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<p>Performance of SCL.</p>
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<p>Comparison of different time series.</p>
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<p>Comparison of the number of input links.</p>
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<p>Comparison of the number of target links.</p>
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<p>Comparison of the number of bots.</p>
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16 pages, 508 KiB  
Article
On-Demand Scheduling of Command and Responses for Low-Power Multihop Wireless Networks
by Mingyu Park and Jeongyeup Paek
Sensors 2021, 21(3), 738; https://doi.org/10.3390/s21030738 - 22 Jan 2021
Cited by 6 | Viewed by 2070
Abstract
Many IoT applications require a mechanism to disseminate commands and collect responses over a wireless network in order to control and collect data from multiple embedded devices. However, severe collisions may occur if a large number of nodes attempt to respond simultaneously and [...] Read more.
Many IoT applications require a mechanism to disseminate commands and collect responses over a wireless network in order to control and collect data from multiple embedded devices. However, severe collisions may occur if a large number of nodes attempt to respond simultaneously and promptly, not only among the responses, but also with the dissemination of commands. This is because low-power wireless network protocols for dissemination and collection have been designed separately. Tuning the parameters of one side of the protocol has clear trade-off between reliability and latency. To address this challenge, we propose SCoRe, an on-demand scheme for joint scheduling of command and responses on multihop low-power wireless networks to improve both reliability and latency simultaneously at runtime. SCoRe gathers the amount of time required by network nodes for dissemination and collection, and allocates relative timeslots to each node recursively over multihop on-demand when (and only when) disseminating a command. While doing so, information exchange occurs only between local neighbor nodes without a need for global routing table nor time synchronization. We implement SCoRe on a low-power embedded platform, and compare with well-known dissemination and collection schemes through both simulations and testbed experiments on 30 devices. Our evaluation results show that SCoRe can improve both latency and reliability without tuning the parameters for one metric, while the legacy schemes require careful parameter selection to match only one side of SCoRe, never both. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>Grid topology for the preliminary simulation and the result.</p>
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<p>SCoRe’s scheduling process overview.</p>
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<p>Slot violation scenario.</p>
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<p>An example of parallel transmission scenario.</p>
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<p>Response and dissemination time update.</p>
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<p>A 3D plots representing Packet Reception Ratio with varying parameters.</p>
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<p>Three-simulation topology with change of root’s position: top-left, top, and middle.</p>
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<p>Simulation results when the root is placed at the top-left corner of the grid topology with <span class="html-italic">M</span> = 3, <span class="html-italic">T<sub>C</sub></span> = 200 ms, <span class="html-italic">K</span> = 5 and varying <span class="html-italic">T<sub>R</sub></span>.</p>
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<p>Simulation results when the root is placed in the middle of the grid topology with <span class="html-italic">M</span> = 3, <span class="html-italic">T<sub>C</sub></span> = 200 ms, <span class="html-italic">K</span> = 5, and varying <span class="html-italic">T<sub>R</sub></span>.</p>
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<p>Simulation results from random topologies with <span class="html-italic">M</span> = 3, <span class="html-italic">T<sub>C</sub></span> = 200 ms, <span class="html-italic">K</span> = 5, and varying <span class="html-italic">T<sub>R</sub></span>.</p>
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<p>Results from the testbed experiments with <span class="html-italic">M</span> = 3, <span class="html-italic">T<sub>C</sub></span> = 200 ms, <span class="html-italic">K</span> = 5, and varying <span class="html-italic">T<sub>R</sub></span>.</p>
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23 pages, 5031 KiB  
Article
Optimizations for Energy Efficiency in Software-Defined Wireless Sensor Networks
by Sorin Buzura, Bogdan Iancu, Vasile Dadarlat, Adrian Peculea and Emil Cebuc
Sensors 2020, 20(17), 4779; https://doi.org/10.3390/s20174779 - 24 Aug 2020
Cited by 23 | Viewed by 3893
Abstract
Software-defined wireless sensor networking (SDWSN) is an emerging networking architecture which is envisioned to become the main enabler for the internet of things (IoT). In this architecture, the sensors plane is managed by a control plane. With this separation, the network management is [...] Read more.
Software-defined wireless sensor networking (SDWSN) is an emerging networking architecture which is envisioned to become the main enabler for the internet of things (IoT). In this architecture, the sensors plane is managed by a control plane. With this separation, the network management is facilitated, and performance is improved in dynamic environments. One of the main issues a sensor environment is facing is the limited lifetime of network devices influenced by high levels of energy consumption. The current work proposes a system design which aims to improve the energy efficiency in an SDWSN by combining the concepts of content awareness and adaptive data broadcast. The purpose is to increase the sensors’ lifespan by reducing the number of generated data packets in the resource-constrained sensors plane of the network. The system has a distributed management approach, with content awareness being implemented at the individual programmable sensor level and the adaptive data broadcast being performed in the control plane. Several simulations were run on historical weather and the results show a significant decrease in network traffic. Compared to similar work in this area which focuses on improving energy efficiency with complex algorithms for routing, clustering, or caching, the current proposal employs simple computing procedures on each network device with a high impact on the overall network performance. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>Traditional WSN architecture.</p>
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<p>Traditional SDWSN architecture.</p>
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<p>Proposed system architecture.</p>
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<p>Custom data payload structures for control and sensor data packets.</p>
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<p>Flow of operations when no packet loss occurs.</p>
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<p>Flow of operations in the resend case when packet loss occurs.</p>
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<p>Test network topology, adapted from [<a href="#B18-sensors-20-04779" class="html-bibr">18</a>].</p>
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<p>Test results for long network lifetime scenario.</p>
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<p>Test results for medium network lifetime scenario.</p>
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<p>Test results for short network lifetime scenario.</p>
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<p>Statistics for non-optimized simulation.</p>
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<p>Statistics for optimized simulation.</p>
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<p>Gain in reducing the number of generated packets with no transmission errors.</p>
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<p>Statistics for the scenarios with packet loss.</p>
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25 pages, 6702 KiB  
Article
Reinforcement Learning-Enabled Cross-Layer Optimization for Low-Power and Lossy Networks under Heterogeneous Traffic Patterns
by Arslan Musaddiq, Zulqar Nain, Yazdan Ahmad Qadri, Rashid Ali and Sung Won Kim
Sensors 2020, 20(15), 4158; https://doi.org/10.3390/s20154158 - 26 Jul 2020
Cited by 17 | Viewed by 4254
Abstract
The next generation of the Internet of Things (IoT) networks is expected to handle a massive scale of sensor deployment with radically heterogeneous traffic applications, which leads to a congested network, calling for new mechanisms to improve network efficiency. Existing protocols are based [...] Read more.
The next generation of the Internet of Things (IoT) networks is expected to handle a massive scale of sensor deployment with radically heterogeneous traffic applications, which leads to a congested network, calling for new mechanisms to improve network efficiency. Existing protocols are based on simple heuristics mechanisms, whereas the probability of collision is still one of the significant challenges of future IoT networks. The medium access control layer of IEEE 802.15.4 uses a distributed coordination function to determine the efficiency of accessing wireless channels in IoT networks. Similarly, the network layer uses a ranking mechanism to route the packets. The objective of this study was to intelligently utilize the cooperation of multiple communication layers in an IoT network. Recently, Q-learning (QL), a machine learning algorithm, has emerged to solve learning problems in energy and computational-constrained sensor devices. Therefore, we present a QL-based intelligent collision probability inference algorithm to optimize the performance of sensor nodes by utilizing channel collision probability and network layer ranking states with the help of an accumulated reward function. The simulation results showed that the proposed scheme achieved a higher packet reception ratio, produces significantly lower control overheads, and consumed less energy compared to current state-of-the-art mechanisms. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>State-transition diagram for Markov decision process (MDP) with <span class="html-italic">m</span> states.</p>
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<p>Formats of RPL control messages.</p>
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<p>Q-learning model environment for intelligent IoT system device.</p>
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<p>Convergence of learning estimate <math display="inline"><semantics> <mrow> <mo>Δ</mo> <mi>Q</mi> </mrow> </semantics></math> for varying the learning rate <math display="inline"><semantics> <mi>α</mi> </semantics></math> (<math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7, <math display="inline"><semantics> <mo>∈</mo> </semantics></math> = 0.7).</p>
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<p>Convergence of learning estimate <math display="inline"><semantics> <mrow> <mo>Δ</mo> <mi>Q</mi> </mrow> </semantics></math> for varying the discount factor <math display="inline"><semantics> <mi>β</mi> </semantics></math> (<math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.7, <math display="inline"><semantics> <mo>∈</mo> </semantics></math> = 0.7).</p>
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<p>Convergence of learning estimate <math display="inline"><semantics> <mrow> <mo>Δ</mo> <mi>Q</mi> </mrow> </semantics></math> in a dynamic network environment (adding new nodes in the network during simulation).</p>
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<p>Comparison of packet reception ratio (PRR) between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Comparison of average E2E packet delay between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Comparison of number of DIO control messages between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Comparison of number of DAO control messages between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Comparison of total control overhead (%) between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Comparison of LMP energy consumption (J) between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Comparison of CPU energy consumption (J) between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Comparison of average Tx energy consumption (J) between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Comparison of average Rx energy consumption (J) between <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7 in a network of 20 to 100 nodes.</p>
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<p>Total energy consumption (J) versus number of transmitted data packets for <span class="html-italic">i</span>CPLA, QU-RPL, SL-RPL, MRHOF, and OF0 with <math display="inline"><semantics> <mi>α</mi> </semantics></math> = 0.3 and <math display="inline"><semantics> <mi>β</mi> </semantics></math> = 0.7.</p>
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<p>Proposed framework for smart sustainable cities applications.</p>
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17 pages, 475 KiB  
Article
An Efficient Superframe Structure with Optimal Bandwidth Utilization and Reduced Delay for Internet of Things Based Wireless Sensor Networks
by Sangrez Khan, Ahmad Naseem Alvi, Muhammad Awais Javed, Byeong-hee Roh and Jehad Ali
Sensors 2020, 20(7), 1971; https://doi.org/10.3390/s20071971 - 1 Apr 2020
Cited by 15 | Viewed by 4017
Abstract
Internet of Things (IoT) is a promising technology that uses wireless sensor networks to enable data collection, monitoring, and transmission from the physical devices to the Internet. Due to its potential large scale usage, efficient routing and Medium Access Control (MAC) techniques are [...] Read more.
Internet of Things (IoT) is a promising technology that uses wireless sensor networks to enable data collection, monitoring, and transmission from the physical devices to the Internet. Due to its potential large scale usage, efficient routing and Medium Access Control (MAC) techniques are vital to meet various application requirements. Most of the IoT applications need low data rate and low powered wireless transmissions and IEEE 802.15.4 standard is mostly used in this regard which offers superframe structure at the MAC layer. However, for IoT applications where nodes have adaptive data traffic, the standard has some limitations such as bandwidth wastage and latency. In this paper, a new superframe structure is proposed that is backward compatible with the existing parameters of the standard. The proposed superframe overcomes limitations of the standard by fine-tuning its superframe structure and squeezing the size of its contention-free slots. Thus, the proposed superframe adjusts its duty cycle according to the traffic requirements and accommodates more nodes in a superframe structure. The analytical results show that our proposed superframe structure has almost 50% less delay, accommodate more nodes and has better link utilization in a superframe as compared to the IEEE 802.15.4 standard. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>IEEE 802.15.4 Beacon enabled mode Superframe format.</p>
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<p>Efficient Superframe Structure.</p>
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<p>GTS request frame format of IEEE 802.15.4.</p>
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<p>Proposed <math display="inline"><semantics> <mrow> <mi>E</mi> <mi>S</mi> <msub> <mi>S</mi> <mrow> <mi>A</mi> <mi>D</mi> <mi>C</mi> </mrow> </msub> </mrow> </semantics></math> algorithm.</p>
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<p><math display="inline"><semantics> <mrow> <mi>E</mi> <mi>S</mi> <msub> <mi>S</mi> <mrow> <mi>A</mi> <mi>D</mi> <mi>C</mi> </mrow> </msub> </mrow> </semantics></math> adjusting its SO against transmitted data.</p>
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<p>Accumulated delay comparison against all ranges of 4 different BO values.</p>
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<p>Accumulated delay for random data traffic.</p>
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<p>GTS utilization of the network for random data requesting nodes.</p>
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<p>GTS utilization of the network for varying range of fixed data requesting nodes.</p>
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<p>Data transmission by all nodes for random data requesting nodes.</p>
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<p>Data transmission by all nodes for varying range of fixed data requesting nodes.</p>
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<p>GTS allocating nodes for random data requesting nodes.</p>
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<p>GTS allocating nodes for varying range of fixed data requesting nodes.</p>
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18 pages, 5795 KiB  
Article
Edge4TSC: Binary Distribution Tree-Enabled Time Series Classification in Edge Environment
by Chao Ma, Xiaochuan Shi, Wei Li and Weiping Zhu
Sensors 2020, 20(7), 1908; https://doi.org/10.3390/s20071908 - 30 Mar 2020
Cited by 11 | Viewed by 2808
Abstract
In the past decade, time series data have been generated from various fields at a rapid speed, which offers a huge opportunity for mining valuable knowledge. As a typical task of time series mining, Time Series Classification (TSC) has attracted lots of attention [...] Read more.
In the past decade, time series data have been generated from various fields at a rapid speed, which offers a huge opportunity for mining valuable knowledge. As a typical task of time series mining, Time Series Classification (TSC) has attracted lots of attention from both researchers and domain experts due to its broad applications ranging from human activity recognition to smart city governance. Specifically, there is an increasing requirement for performing classification tasks on diverse types of time series data in a timely manner without costly hand-crafting feature engineering. Therefore, in this paper, we propose a framework named Edge4TSC that allows time series to be processed in the edge environment, so that the classification results can be instantly returned to the end-users. Meanwhile, to get rid of the costly hand-crafting feature engineering process, deep learning techniques are applied for automatic feature extraction, which shows competitive or even superior performance compared to state-of-the-art TSC solutions. However, because time series presents complex patterns, even deep learning models are not capable of achieving satisfactory classification accuracy, which motivated us to explore new time series representation methods to help classifiers further improve the classification accuracy. In the proposed framework Edge4TSC, by building the binary distribution tree, a new time series representation method was designed for addressing the classification accuracy concern in TSC tasks. By conducting comprehensive experiments on six challenging time series datasets in the edge environment, the potential of the proposed framework for its generalization ability and classification accuracy improvement is firmly validated with a number of helpful insights. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>Overall architecture of Edge4TSC. TSC = Time Series Classification.</p>
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<p>An example for Binary Subsequence Tree (BST) construction procedure.</p>
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<p>An example for Binary Distribution Tree (BDT) transformation procedure.</p>
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<p>An example for BDT-based representation generation.</p>
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<p>Network structure and hyper-parameter setting of deep learning classifiers. MLP = Multi-Layer Perceptron; FCN = Fully Convolutional Network; ResNet = Residual Network; ReLU = Rectified Linear Unit; GAP = Global Average Pooling.</p>
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<p>Time consumption of end device and edge device. 1NN = 1-Nearest-Neighbor.</p>
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<p>Impact of split ratio on TSC accuracy.</p>
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<p>Impact of bin number on TSC accuracy.</p>
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<p>Impact of BDT level on TSC accuracy.</p>
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23 pages, 5168 KiB  
Article
Traffic Offloading in Multicast Device-to-Device Cellular Networks: A Combinatorial Auction-Based Matching Algorithm
by Devarani Devi Ningombam and Seokjoo Shin
Sensors 2020, 20(4), 1128; https://doi.org/10.3390/s20041128 - 19 Feb 2020
Cited by 4 | Viewed by 2664
Abstract
In the last few years, multicast device-to-device (D2D) cellular networks has become a highly attractive area of research. However, a particularly challenging class of issues in this area is data traffic, which increases due to increase in video and audio streaming applications. Therefore, [...] Read more.
In the last few years, multicast device-to-device (D2D) cellular networks has become a highly attractive area of research. However, a particularly challenging class of issues in this area is data traffic, which increases due to increase in video and audio streaming applications. Therefore, there is need for smart spectrum management policies. In this paper, we consider a fractional frequency reuse (FFR) technique which divides the whole spectrum into multiple sections and allows reusing of spectrum resources between the conventional cellular users and multicast D2D users in a non-orthogonal scenario. Since conventional cellular users and multicast D2D users shared same resources simultaneously, they generate severe data traffic and high communication overhead. To overcome these issues, in this paper we propose Lagrange relaxation technique to solve the non-convex problem and combinatorial auction-based matching algorithm to select the most desirable resource reuse partners by fulfilling the quality of service (QoS) requirements for both the conventional cellular users and multicast D2D users. Then, we formulate an optimization problem to maximize the overall system performance with least computational complexity. We demonstrate that our method can exploit a higher data rate, spectrum efficiency, traffic offload rate, coverage probability, and lower computational complexity. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>Spectrum partitioned in fractional frequency reuse (FFR) scheme using three 120°-directional antennas.</p>
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<p>(<b>a</b>) System model for multicast device-to-device (D2D) communications, and (<b>b</b>) uplink interference scenarios.</p>
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<p>Selection of resource reuse matching between conventional cellular users and multicast D2D groups.</p>
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<p>Data rate vs. signal-to-interference-plus-noise ratio (SINR) performance.</p>
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<p>Cumulative Distribution Function (CDF) of spectral efficiency (SE) performance.</p>
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<p>Coverage probability vs. SINR performance.</p>
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<p>Data rate vs. multicast D2D group size.</p>
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<p>Complexity vs. no. of multicast D2D groups.</p>
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<p>Data rate vs. no. of iterations.</p>
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<p>Traffic offloading vs. no. of multicast D2D groups.</p>
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<p>Energy efficiency vs. multicast D2D group size.</p>
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<p>Revenue vs. reserve price.</p>
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<p>System revenue vs. no. of D2D receivers in a multicast group.</p>
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<p>Data rate vs. no. of iterations.</p>
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Review

Jump to: Research

32 pages, 1476 KiB  
Review
Resource Management in Cloud Radio Access Network: Conventional and New Approaches
by Rehenuma Tasnim Rodoshi, Taewoon Kim and Wooyeol Choi
Sensors 2020, 20(9), 2708; https://doi.org/10.3390/s20092708 - 9 May 2020
Cited by 46 | Viewed by 6084
Abstract
Cloud radio access network (C-RAN) is a promising mobile wireless sensor network architecture to address the challenges of ever-increasing mobile data traffic and network costs. C-RAN is a practical solution to the strict energy-constrained wireless sensor nodes, often found in Internet of Things [...] Read more.
Cloud radio access network (C-RAN) is a promising mobile wireless sensor network architecture to address the challenges of ever-increasing mobile data traffic and network costs. C-RAN is a practical solution to the strict energy-constrained wireless sensor nodes, often found in Internet of Things (IoT) applications. Although this architecture can provide energy efficiency and reduce cost, it is a challenging task in C-RAN to utilize the resources efficiently, considering the dynamic real-time environment. Several research works have proposed different methodologies for effective resource management in C-RAN. This study performs a comprehensive survey on the state-of-the-art resource management techniques that have been proposed recently for this architecture. The resource management techniques are categorized into computational resource management (CRM) and radio resource management (RRM) techniques. Then both of the techniques are further classified and analyzed based on the strategies used in the studies. Remote radio head (RRH) clustering schemes used in CRM techniques are discussed extensively. In this research work, the investigated performance metrics and their validation techniques are critically analyzed. Moreover, other important challenges and open research issues for efficient resource management in C-RAN are highlighted to provide future research direction. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>Organization of this survey.</p>
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<p>(<b>a</b>) Architecture of RAN with distributed RRH, (<b>b</b>) Architecture of cloud RAN.</p>
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<p>Types of C-RAN: (<b>a</b>) fully centralized C-RAN, (<b>b</b>) partially centralized C-RAN.</p>
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<p>Resource management techniques in C-RAN.</p>
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<p>BBU-RRH mapping: (<b>a</b>) one-to-one mapping (<b>b</b>) one-to-many mapping.</p>
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26 pages, 1349 KiB  
Review
Advancing the State of the Fog Computing to Enable 5G Network Technologies
by Yahui Meng, Muhammad Ali Naeem, Alaa Omran Almagrabi, Rashid Ali and Hyung Seok Kim
Sensors 2020, 20(6), 1754; https://doi.org/10.3390/s20061754 - 21 Mar 2020
Cited by 35 | Viewed by 6336
Abstract
Fog Computing (FC) is promising to Internet architecture for the emerging of modern technological approaches such as Fifth Generation (5G) networks and the Internet of Things (IoT). These are the advanced technologies that enable Internet architecture to enhance the data dissemination services based [...] Read more.
Fog Computing (FC) is promising to Internet architecture for the emerging of modern technological approaches such as Fifth Generation (5G) networks and the Internet of Things (IoT). These are the advanced technologies that enable Internet architecture to enhance the data dissemination services based on numerous sensors generating continuous sensory information. It is tough for the current Internet architecture to meet up with the growing demands of the users for such a massive amount of information. Therefore, it needs to adopt modern technologies for efficient data dissemination services across the Internet. Thus, the FC and 5G are updating the data transmission using new technological approaches that are intelligently processing data to provide enhanced communications. This study proposes necessary measures to boost the growth of FC to 5G network usage. It is done by taking an extensive review of how 5G operates as well as studying its taxonomy, the idea of IoT, reviewed projects on IoT applicability, comparison of computing technologies, and the importance of FC. Moreover, it elaborates dynamic issues of computing network technologies, and information is provided on how to remedy these for future recommendations in the field of research and computing network technologies. This paper heavily focuses on the applications of FC as an enabler to the 5G network by identifying the necessary services and network-oriented features that are needed to be used in the place for an improved future enterprise network technology. Full article
(This article belongs to the Special Issue Intelligent Wireless Technologies for Future Sensor Networks)
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<p>Consumer IoT applications.</p>
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<p>WM-FOG software stack.</p>
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<p>A three-layered Fog Computing network architecture with 5G network.</p>
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<p>Applications of Fog Computing.</p>
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