19,451 research outputs found
A Survey on High-Speed Railway Communications: A Radio Resource Management Perspective
High-speed railway (HSR) communications will become a key feature supported
by intelligent transportation communication systems. The increasing demand for
HSR communications leads to significant attention on the study of radio
resource management (RRM), which enables efficient resource utilization and
improved system performance. RRM design is a challenging problem due to
heterogenous quality of service (QoS) requirements and dynamic characteristics
of HSR wireless communications. The objective of this paper is to provide an
overview on the key issues that arise in the RRM design for HSR wireless
communications. A detailed description of HSR communication systems is first
presented, followed by an introduction on HSR channel models and
characteristics, which are vital to the cross-layer RRM design. Then we provide
a literature survey on state-of-the-art RRM schemes for HSR wireless
communications, with an in-depth discussion on various RRM aspects including
admission control, mobility management, power control and resource allocation.
Finally, this paper outlines the current challenges and open issues in the area
of RRM design for HSR wireless communications.Comment: 40 pages, 10 figures. Submitted to Computer Communication
A Survey on QoE-oriented Wireless Resources Scheduling
Future wireless systems are expected to provide a wide range of services to
more and more users. Advanced scheduling strategies thus arise not only to
perform efficient radio resource management, but also to provide fairness among
the users. On the other hand, the users' perceived quality, i.e., Quality of
Experience (QoE), is becoming one of the main drivers within the schedulers
design. In this context, this paper starts by providing a comprehension of what
is QoE and an overview of the evolution of wireless scheduling techniques.
Afterwards, a survey on the most recent QoE-based scheduling strategies for
wireless systems is presented, highlighting the application/service of the
different approaches reported in the literature, as well as the parameters that
were taken into account for QoE optimization. Therefore, this paper aims at
helping readers interested in learning the basic concepts of QoE-oriented
wireless resources scheduling, as well as getting in touch with its current
research frontier.Comment: Revised version: updated according to the most recent related
literature; added references; corrected typo
A Taxonomy and Future Directions for Sustainable Cloud Computing: 360 Degree View
The cloud computing paradigm offers on-demand services over the Internet and
supports a wide variety of applications. With the recent growth of Internet of
Things (IoT) based applications the usage of cloud services is increasing
exponentially. The next generation of cloud computing must be energy-efficient
and sustainable to fulfil the end-user requirements which are changing
dynamically. Presently, cloud providers are facing challenges to ensure the
energy efficiency and sustainability of their services. The usage of large
number of cloud datacenters increases cost as well as carbon footprints, which
further effects the sustainability of cloud services. In this paper, we propose
a comprehensive taxonomy of sustainable cloud computing. The taxonomy is used
to investigate the existing techniques for sustainability that need careful
attention and investigation as proposed by several academic and industry
groups. Further, the current research on sustainable cloud computing is
organized into several categories: application design, sustainability metrics,
capacity planning, energy management, virtualization, thermal-aware scheduling,
cooling management, renewable energy and waste heat utilization. The existing
techniques have been compared and categorized based on the common
characteristics and properties. A conceptual model for sustainable cloud
computing has been proposed along with discussion on future research
directions.Comment: 68 pages, 38 figures, ACM Computing Surveys, 201
Intelligent Processing in Vehicular Ad hoc Networks: a Survey
The intelligent Processing technique is more and more attractive to
researchers due to its ability to deal with key problems in Vehicular Ad hoc
networks. However, several problems in applying intelligent processing
technologies in VANETs remain open. The existing applications are
comprehensively reviewed and discussed, and classified into different
categories in this paper. Their strategies, advantages/disadvantages, and
performances are elaborated. By generalizing different tactics in various
applications related to different scenarios of VANETs and evaluating their
performances, several promising directions for future research have been
suggested.Comment: 11pages, 5 figure
Resource Management of energy-aware Cognitive Radio Networks and cloud-based Infrastructures
The field of wireless networks has been rapidly developed during the past
decade due to the increasing popularity of the mobile devices. The great demand
for mobility and connectivity makes wireless networking a field whose
continuous technological development is very important as new challenges and
issues are arising. Many scientists and researchers are currently engaged in
developing new approaches and optimization methods in several topics of
wireless networking. This survey paper study works from the following topics:
Cognitive Radio Networks, Interactive Broadcasting, Energy Efficient Networks,
Cloud Computing and Resource Management, Interactive Marketing and
Optimization
Energy Efficient User Association and Power Allocation in Millimeter Wave Based Ultra Dense Networks with Energy Harvesting Base Stations
Millimeter wave (mmWave) communication technologies have recently emerged as
an attractive solution to meet the exponentially increasing demand on mobile
data traffic. Moreover, ultra dense networks (UDNs) combined with mmWave
technology are expected to increase both energy efficiency and spectral
efficiency. In this paper, user association and power allocation in mmWave
based UDNs is considered with attention to load balance constraints, energy
harvesting by base stations, user quality of service requirements, energy
efficiency, and cross-tier interference limits. The joint user association and
power optimization problem is modeled as a mixed-integer programming problem,
which is then transformed into a convex optimization problem by relaxing the
user association indicator and solved by Lagrangian dual decomposition. An
iterative gradient user association and power allocation algorithm is proposed
and shown to converge rapidly to an optimal point. The complexity of the
proposed algorithm is analyzed and the effectiveness of the proposed scheme
compared with existing methods is verified by simulations.Comment: to appear, IEEE Journal on Selected Areas in Communications, 201
Internet Resource Pricing Models, Mechanisms, and Methods
With the fast development of video and voice network applications, CDN
(Content Distribution Networks) and P2P (Peer-to-Peer) content distribution
technologies have gradually matured. How to effectively use Internet resources
thus has attracted more and more attentions. For the study of resource pricing,
a whole pricing strategy containing pricing models, mechanisms and methods
covers all the related topics. We first introduce three basic Internet resource
pricing models through an Internet cost analysis. Then, with the evolution of
service types, we introduce several corresponding mechanisms which can ensure
pricing implementation and resource allocation. On network resource pricing
methods, we discuss the utility optimization in economics, and emphasize two
classes of pricing methods (including system optimization and entities'
strategic optimizations). Finally, we conclude the paper and forecast the
research direction on pricing strategy which is applicable to novel service
situation in the near future.Comment: Submitted to Networking Science for peer revie
Bi-Objective Optimization for Energy Aware Internet of Things Service Composition
In recent years, service-oriented-based Internet of Things (IoT) has received
massive attention from research and industry. Integrating and composing smart
objects functionalities or their services is required to create and promote
more complex IoT applications with advanced features. When many smart objects
are deployed, selecting the most appropriate set of smart objects to compose a
service by considering both energy and quality of service (QoS) is an essential
and challenging task. In this paper, we reduced the problem of finding an
optimal balance between QoS level and the consumed energy of the IoT service
composition to a bi-objective shortest path optimization (BSPO) problem and
used an exact algorithm named pulse to solve the problem. The BSPO has two
objectives, minimizing the QoS including execution time, network latency, and
service price, and minimize the energy consumption of the composite service.
Experimental evaluations show that the proposed approach has short execution
time in various complex service profiles. Meanwhile, it can obtain good
performance in energy consumption and thus network lifetime while maintaining a
reasonable QoS level
Effective Capacity in Wireless Networks: A Comprehensive Survey
Low latency applications, such as multimedia communications, autonomous
vehicles, and Tactile Internet are the emerging applications for
next-generation wireless networks, such as 5th generation (5G) mobile networks.
Existing physical-layer channel models, however, do not explicitly consider
quality-of-service (QoS) aware related parameters under specific delay
constraints. To investigate the performance of low-latency applications in
future networks, a new mathematical framework is needed. Effective capacity
(EC), which is a link-layer channel model with QoS-awareness, can be used to
investigate the performance of wireless networks under certain statistical
delay constraints. In this paper, we provide a comprehensive survey on existing
works, that use the EC model in various wireless networks. We summarize the
work related to EC for different networks such as cognitive radio networks
(CRNs), cellular networks, relay networks, adhoc networks, and mesh networks.
We explore five case studies encompassing EC operation with different design
and architectural requirements. We survey various delay-sensitive applications
such as voice and video with their EC analysis under certain delay constraints.
We finally present the future research directions with open issues covering EC
maximization
A Survey on Low Latency Towards 5G: RAN, Core Network and Caching Solutions
The fifth generation (5G) wireless network technology is to be standardized
by 2020, where main goals are to improve capacity, reliability, and energy
efficiency, while reducing latency and massively increasing connection density.
An integral part of 5G is the capability to transmit touch perception type
real-time communication empowered by applicable robotics and haptics equipment
at the network edge. In this regard, we need drastic changes in network
architecture including core and radio access network (RAN) for achieving
end-to-end latency on the order of 1 ms. In this paper, we present a detailed
survey on the emerging technologies to achieve low latency communications
considering three different solution domains: RAN, core network, and caching.
We also present a general overview of 5G cellular networks composed of software
defined network (SDN), network function virtualization (NFV), caching, and
mobile edge computing (MEC) capable of meeting latency and other 5G
requirements.Comment: Accepted in IEEE Communications Surveys and Tutorial
- …