5,272 research outputs found
A study of research trends and issues in wireless ad hoc networks
Ad hoc network enables network creation on the fly without support of any
predefined infrastructure. The spontaneous erection of networks in anytime and
anywhere fashion enables development of various novel applications based on ad
hoc networks. However, at the same ad hoc network presents several new
challenges. Different research proposals have came forward to resolve these
challenges. This chapter provides a survey of current issues, solutions and
research trends in wireless ad hoc network. Even though various surveys are
already available on the topic, rapid developments in recent years call for an
updated account on this topic. The chapter has been organized as follows. In
the first part of the chapter, various ad hoc network's issues arising at
different layers of TCP/IP protocol stack are presented. An overview of
research proposals to address each of these issues is also provided. The second
part of the chapter investigates various emerging models of ad hoc networks,
discusses their distinctive properties and highlights various research issues
arising due to these properties. We specifically provide discussion on ad hoc
grids, ad hoc clouds, wireless mesh networks and cognitive radio ad hoc
networks. The chapter ends with presenting summary of the current research on
ad hoc network, ignored research areas and directions for further research
Data Management in Industry 4.0: State of the Art and Open Challenges
Information and communication technologies are permeating all aspects of
industrial and manufacturing systems, expediting the generation of large
volumes of industrial data. This article surveys the recent literature on data
management as it applies to networked industrial environments and identifies
several open research challenges for the future. As a first step, we extract
important data properties (volume, variety, traffic, criticality) and identify
the corresponding data enabling technologies of diverse fundamental industrial
use cases, based on practical applications. Secondly, we provide a detailed
outline of recent industrial architectural designs with respect to their data
management philosophy (data presence, data coordination, data computation) and
the extent of their distributiveness. Then, we conduct a holistic survey of the
recent literature from which we derive a taxonomy of the latest advances on
industrial data enabling technologies and data centric services, spanning all
the way from the field level deep in the physical deployments, up to the cloud
and applications level. Finally, motivated by the rich conclusions of this
critical analysis, we identify interesting open challenges for future research.
The concepts presented in this article thematically cover the largest part of
the industrial automation pyramid layers. Our approach is multidisciplinary, as
the selected publications were drawn from two fields; the communications,
networking and computation field as well as the industrial, manufacturing and
automation field. The article can help the readers to deeply understand how
data management is currently applied in networked industrial environments, and
select interesting open research opportunities to pursue
The Proceedings of First Work-in-Progress Session of The CSI International Symposium on Real-Time and Embedded Systems and Technologies
The present volume contains the proceedings of RTEST WiP 2018, chaired by
Marco Caccamo, University of Illinois at Urbana-Champaign. This event has been
organized by the School of Electrical and Computer Engineering at the
University of Tehran, in conjunction with the Department of Computer
Engineering at Sharif University of Technology, Tehran, Iran. The topics of
interest in RTEST WiP span over all theoretical and application-oriented
aspects, reporting design, analysis, implementation, evaluation, and empirical
results, of real-time and embedded systems, internet-of-things, and
cyber-physical systems. The program committee of RTEST 2018 consists of 54 top
researchers in the mentioned fields from top universities, industries, and
research centers around the world. RTEST 2018 has received a total of 41
submissions, out of which we have accepted 14 regular papers and 4
work-in-progress papers. Each submission has been reviewed by 3 to 5
independent referees, for its quality, originality, contribution, clarity of
presentation, and relevance to the symposium topics
A Survey on Mobile Edge Networks: Convergence of Computing, Caching and Communications
As the explosive growth of smart devices and the advent of many new
applications, traffic volume has been growing exponentially. The traditional
centralized network architecture cannot accommodate such user demands due to
heavy burden on the backhaul links and long latency. Therefore, new
architectures which bring network functions and contents to the network edge
are proposed, i.e., mobile edge computing and caching. Mobile edge networks
provide cloud computing and caching capabilities at the edge of cellular
networks. In this survey, we make an exhaustive review on the state-of-the-art
research efforts on mobile edge networks. We first give an overview of mobile
edge networks including definition, architecture and advantages. Next, a
comprehensive survey of issues on computing, caching and communication
techniques at the network edge is presented respectively. The applications and
use cases of mobile edge networks are discussed. Subsequently, the key enablers
of mobile edge networks such as cloud technology, SDN/NFV and smart devices are
discussed. Finally, open research challenges and future directions are
presented as well
Fundamental Green Tradeoffs: Progresses, Challenges, and Impacts on 5G Networks
With years of tremendous traffic and energy consumption growth, green radio
has been valued not only for theoretical research interests but also for the
operational expenditure reduction and the sustainable development of wireless
communications. Fundamental green tradeoffs, served as an important framework
for analysis, include four basic relationships: spectrum efficiency (SE) versus
energy efficiency (EE), deployment efficiency (DE) versus energy efficiency
(EE), delay (DL) versus power (PW), and bandwidth (BW) versus power (PW). In
this paper, we first provide a comprehensive overview on the extensive on-going
research efforts and categorize them based on the fundamental green tradeoffs.
We will then focus on research progresses of 4G and 5G communications, such as
orthogonal frequency division multiplexing (OFDM) and non-orthogonal
aggregation (NOA), multiple input multiple output (MIMO), and heterogeneous
networks (HetNets). We will also discuss potential challenges and impacts of
fundamental green tradeoffs, to shed some light on the energy efficient
research and design for future wireless networks.Comment: revised from IEEE Communications Surveys & Tutorial
Underwater Optical Wireless Communications, Networking, and Localization: A Survey
Underwater wireless communications can be carried out through acoustic, radio
frequency (RF), and optical waves. Compared to its bandwidth limited acoustic
and RF counterparts, underwater optical wireless communications (UOWCs) can
support higher data rates at low latency levels. However, severe aquatic
channel conditions (e.g., absorption, scattering, turbulence, etc.) pose great
challenges for UOWCs and significantly reduce the attainable communication
ranges, which necessitates efficient networking and localization solutions.
Therefore, we provide a comprehensive survey on the challenges, advances, and
prospects of underwater optical wireless networks (UOWNs) from a layer by layer
perspective which includes: 1) Potential network architectures; 2) Physical
layer issues including propagation characteristics, channel modeling, and
modulation techniques 3) Data link layer problems covering link configurations,
link budgets, performance metrics, and multiple access schemes; 4) Network
layer topics containing relaying techniques and potential routing algorithms;
5) Transport layer subjects such as connectivity, reliability, flow and
congestion control; 6) Application layer goals and state-of-the-art UOWN
applications, and 7) Localization and its impacts on UOWN layers. Finally, we
outline the open research challenges and point out the future directions for
underwater optical wireless communications, networking, and localization
research.Comment: This manuscript is submitted to IEEE Communication Surveys and
Tutorials for possible publicatio
Wireless Network Design for Control Systems: A Survey
Wireless networked control systems (WNCS) are composed of spatially
distributed sensors, actuators, and con- trollers communicating through
wireless networks instead of conventional point-to-point wired connections. Due
to their main benefits in the reduction of deployment and maintenance costs,
large flexibility and possible enhancement of safety, WNCS are becoming a
fundamental infrastructure technology for critical control systems in
automotive electrical systems, avionics control systems, building management
systems, and industrial automation systems. The main challenge in WNCS is to
jointly design the communication and control systems considering their tight
interaction to improve the control performance and the network lifetime. In
this survey, we make an exhaustive review of the literature on wireless network
design and optimization for WNCS. First, we discuss what we call the critical
interactive variables including sampling period, message delay, message
dropout, and network energy consumption. The mutual effects of these
communication and control variables motivate their joint tuning. We discuss the
effect of controllable wireless network parameters at all layers of the
communication protocols on the probability distribution of these interactive
variables. We also review the current wireless network standardization for WNCS
and their corresponding methodology for adapting the network parameters.
Moreover, we discuss the analysis and design of control systems taking into
account the effect of the interactive variables on the control system
performance. Finally, we present the state-of-the-art wireless network design
and optimization for WNCS, while highlighting the tradeoff between the
achievable performance and complexity of various approaches. We conclude the
survey by highlighting major research issues and identifying future research
directions.Comment: 37 pages, 17 figures, 4 table
All One Needs to Know about Fog Computing and Related Edge Computing Paradigms: A Complete Survey
With the Internet of Things (IoT) becoming part of our daily life and our
environment, we expect rapid growth in the number of connected devices. IoT is
expected to connect billions of devices and humans to bring promising
advantages for us. With this growth, fog computing, along with its related edge
computing paradigms, such as multi-access edge computing (MEC) and cloudlet,
are seen as promising solutions for handling the large volume of
security-critical and time-sensitive data that is being produced by the IoT. In
this paper, we first provide a tutorial on fog computing and its related
computing paradigms, including their similarities and differences. Next, we
provide a taxonomy of research topics in fog computing, and through a
comprehensive survey, we summarize and categorize the efforts on fog computing
and its related computing paradigms. Finally, we provide challenges and future
directions for research in fog computing.Comment: 48 pages, 7 tables, 11 figures, 450 references. The data (categories
and features/objectives of the papers) of this survey are now available
publicly. Accepted by Elsevier Journal of Systems Architectur
MAC Protocols for Terahertz Communication: A Comprehensive Survey
Terahertz communication is emerging as a future technology to support
Terabits per second link with highlighting features as high throughput and
negligible latency. However, the unique features of the Terahertz band such as
high path loss, scattering and reflection pose new challenges and results in
short communication distance. The antenna directionality, in turn, is required
to enhance the communication distance and to overcome the high path loss.
However, these features in combine negate the use of traditional Medium access
protocols. Therefore novel MAC protocol designs are required to fully exploit
their potential benefits including efficient channel access, control message
exchange, link establishment, mobility management, and line-of-sight blockage
mitigation. An in-depth survey of Terahertz MAC protocols is presented in this
paper. The paper highlights the key features of the Terahertz band which should
be considered while designing an efficient Terahertz MAC protocol, and the
decisions which if taken at Terahertz MAC layer can enhance the network
performance. Different Terahertz applications at macro and nano scales are
highlighted with design requirements for their MAC protocols. The MAC protocol
design issues and considerations are highlighted. Further, the existing MAC
protocols are also classified based on network topology, channel access
mechanisms, and link establishment strategies as Transmitter and Receiver
initiated communication. The open challenges and future research directions on
Terahertz MAC protocols are also highlighted.Comment: Submitted to IEEE Communication Surveys and Tutorials Journa
Reconfigurable Wireless Networks
Driven by the advent of sophisticated and ubiquitous applications, and the
ever-growing need for information, wireless networks are without a doubt
steadily evolving into profoundly more complex and dynamic systems. The user
demands are progressively rampant, while application requirements continue to
expand in both range and diversity. Future wireless networks, therefore, must
be equipped with the ability to handle numerous, albeit challenging
requirements. Network reconfiguration, considered as a prominent network
paradigm, is envisioned to play a key role in leveraging future network
performance and considerably advancing current user experiences. This paper
presents a comprehensive overview of reconfigurable wireless networks and an
in-depth analysis of reconfiguration at all layers of the protocol stack. Such
networks characteristically possess the ability to reconfigure and adapt their
hardware and software components and architectures, thus enabling flexible
delivery of broad services, as well as sustaining robust operation under highly
dynamic conditions. The paper offers a unifying framework for research in
reconfigurable wireless networks. This should provide the reader with a
holistic view of concepts, methods, and strategies in reconfigurable wireless
networks. Focus is given to reconfigurable systems in relatively new and
emerging research areas such as cognitive radio networks, cross-layer
reconfiguration and software-defined networks. In addition, modern networks
have to be intelligent and capable of self-organization. Thus, this paper
discusses the concept of network intelligence as a means to enable
reconfiguration in highly complex and dynamic networks. Finally, the paper is
supported with several examples and case studies showing the tremendous impact
of reconfiguration on wireless networks.Comment: 28 pages, 26 figures; Submitted to the Proceedings of the IEEE (a
special issue on Reconfigurable Systems
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