50,258 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
Internet Protocol Version 6: Dead or Alive?
Internet Protocol (IP) is the narrow waist of multilayered Internet protocol
stack which defines the rules for data sent across networks. IPv4 is the fourth
version of IP and first commercially available for deployment set by ARPANET in
1983 which is a 32 bit long address and can support up to 232 devices. In April
2017, all Regional Internet Registries (RIRs) confirmed that IPv4 addresses are
exhausted and cannot be allocated anymore implying any new organization
requesting a block of Internet addresses will be allocated IPv6. This creates
troubles of interoperability, migration and deployment, and therefore
organizations hesitated to use IPv6 borrowing IPv4 addresses from other big
organizations instead. Currently, when IPv4 is not available, and IPv6 is not
adopted for around 20 years, the question arises whether IPv6 will still be
accepted by the computer society or will it have an end of life soon with
alternate better protocol such as ID based networks taking its place. This
paper claims that IPv6 has lost its deployment window and can be safely skipped
when new ID based protocols are available which not only have simple
interoperability, deployment and migration guidelines but also provide advanced
features as compared to IPv6. The paper provides answers to these questions
with a comprehensive comparison of IPv6 with its available alternatives and
reasons of IPv6 failures in its adoption. Finally, the paper declares IPv6 as a
dead protocol and suggests to use newer available protocols in future.Comment: 16:198:553 Rutgers CS Course Pape
Fast User-Guided Video Object Segmentation by Interaction-and-Propagation Networks
We present a deep learning method for the interactive video object
segmentation. Our method is built upon two core operations, interaction and
propagation, and each operation is conducted by Convolutional Neural Networks.
The two networks are connected both internally and externally so that the
networks are trained jointly and interact with each other to solve the complex
video object segmentation problem. We propose a new multi-round training scheme
for the interactive video object segmentation so that the networks can learn
how to understand the user's intention and update incorrect estimations during
the training. At the testing time, our method produces high-quality results and
also runs fast enough to work with users interactively. We evaluated the
proposed method quantitatively on the interactive track benchmark at the DAVIS
Challenge 2018. We outperformed other competing methods by a significant margin
in both the speed and the accuracy. We also demonstrated that our method works
well with real user interactions.Comment: CVPR 201
BaPu: Efficient and Practical Bunching of Access Point Uplinks
Today's increasing demand for wirelessly uploading a large volume of User
Generated Content (UGC) is still significantly limited by the throttled
backhaul of residential broadband (typically between 1 and 3Mbps). We propose
BaPu, a carefully designed system with implementation for bunching WiFi access
points' backhaul to achieve a high aggregated throughput. BaPu is inspired by a
decade of networking design principles and techniques to enable efficient TCP
over wireless links and multipath. BaPu aims to achieve two major goals:1)
requires no client modification for easy incremental adoption; 2) supports not
only UDP, but also TCP traffic to greatly extend its applicability to a broad
class of popular applications such as HD streaming or large file transfer. We
prototyped BaPu with commodity hardware. Our extensive experiments shows that
despite TCP's sensitivity to typical channel factors such as high wireless
packet loss, out-of-order packets arrivals due to multipath, heterogeneous
backhaul capacity, and dynamic delays, BaPu achieves a backhaul aggregation up
to 95% of the theoretical maximum throughput for UDP and 88% for TCP. We also
empirically estimate the potential idle bandwidth that can be harnessed from
residential broadband.Comment: 15 pages, 17 figures, experiment results obtained from real prototype
system. BaPu is a sub-project under the Open Infrastructure project at the
Wireless Networks Lab, College of Computer and Information Science in
Northeastern University.
(http://www.ccs.neu.edu/home/noubir/projects/openinfrastructure
Distortion-Aware Concurrent Multipath Transfer for Mobile Video Streaming in Heterogeneous Wireless Networks
The massive proliferation of wireless infrastructures with complementary
characteristics prompts the bandwidth aggregation for Concurrent Multipath
Transfer (CMT) over heterogeneous access networks. Stream Control Transmission
Protocol (SCTP) is the standard transport-layer solution to enable CMT in
multihomed communication environments. However, delivering high-quality
streaming video with the existing CMT solutions still remains problematic due
to the stringent QoS (Quality of Service) requirements and path asymmetry in
heterogeneous wireless networks. In this paper, we advance the state of the art
by introducing video distortion into the decision process of multipath data
transfer. The proposed Distortion-Aware Concurrent Multipath Transfer (CMT-DA)
solution includes three phases: 1) per-path status estimation and congestion
control; 2) quality-optimal video flow rate allocation; 3) delay and loss
controlled data retransmission. The term `flow rate allocation' indicates
dynamically picking appropriate access networks and assigning the transmission
rates. We analytically formulate the data distribution over multiple
communication paths to minimize the end-to-end video distortion and derive the
solution based on the utility maximization theory. The performance of the
proposed CMT-DA is evaluated through extensive semi-physical emulations in
Exata involving H.264 video streaming. Experimental results show that CMT-DA
outperforms the reference schemes in terms of video PSNR (Peak Signal-to-Noise
Ratio), goodput, and inter-packet delay.Comment: This paper has already accepted for publication in IEEE Transactions
on Mobile Computing on Jun, 23rd, 201
A Survey and Taxonomy of Urban Traffic Management: Towards Vehicular Networks
Urban Traffic Management (UTM) topics have been tackled since long time,
mainly by civil engineers and by city planners. The introduction of new
communication technologies - such as cellular systems, satellite positioning
systems and inter-vehicle communications - has significantly changed the way
researchers deal with UTM issues. In this survey, we provide a review and a
classification of how UTM has been addressed in the literature. We start from
the recent achievements of "classical" approaches to urban traffic estimation
and optimization, including methods based on the analysis of data collected by
fixed sensors (e.g., cameras and radars), as well as methods based on
information provided by mobile phones, such as Floating Car Data (FCD).
Afterwards, we discuss urban traffic optimization, presenting the most recent
works on traffic signal control and vehicle routing control. Then, after
recalling the main concepts of Vehicular Ad-Hoc Networks (VANETs), we classify
the different VANET-based approaches to UTM, according to three categories
("pure" VANETs, hybrid vehicular-sensor networks and hybrid vehicular-cellular
networks), while illustrating the major research issues for each of them. The
main objective of this survey is to provide a comprehensive view on UTM to
researchers with focus on VANETs, in order to pave the way for the design and
development of novel techniques for mitigating urban traffic problems, based on
inter-vehicle communications
Towards Enabling Novel Edge-Enabled Applications
Edge computing has emerged as a distributed computing paradigm to overcome
practical scalability limits of cloud computing. The main principle of edge
computing is to leverage on computational resources outside of the cloud for
performing computations closer to data sources, avoiding unnecessary data
transfers to the cloud and enabling faster responses for clients.
While this paradigm has been successfully employed to improve response times
in some contexts, mostly by having clients perform pre-processing and/or
filtering of data, or by leveraging on distributed caching infrastructures, we
argue that the combination of edge and cloud computing has the potential to
enable novel applications. However, to do so, some significant research
challenges have to be tackled by the computer science community. In this paper,
we discuss different edge resources and their potential use, motivated by
envisioned use cases. We then discuss concrete research challenges that are in
the critical path towards realizing our edge vision. We conclude by proposing a
research agenda to allow the full exploitation of the potential for the
emerging hybrid cloud/edge paradigm
Web Application for Collaborative Semantic Web Information Architecture
In this paper is analyzed the prototyping of the information visualization on
a Web Application for community purposes in a collaborative environment
representing an evolution of the actual social networks like Facebook,
Instagram, Twitter, Linkedin, VirgilioPeople,... The intent of this work is to
identify the most common features of Web App for the information visualization
based on the Semantic Web and discuss how they support the user's requirements
in a "collaborative" environment. A solution for the context-aware development
of UI is based on "joint meaning" understood as a joint construal of the
creator of the community contents and the user of the community contents thanks
to the context and interface adaptation using the faced taxonomy with the
Semantic Web. A proof-of concept prototype allows showing that the proposed
methodological approach can also easily be applied to existing presentation
components, built with different languages and/or component technologies.Comment: 7 pages, 3 figures, 2 tables, for details see:
http://www.maxdalmas.co
Edge Intelligence: The Confluence of Edge Computing and Artificial Intelligence
Along with the rapid developments in communication technologies and the surge
in the use of mobile devices, a brand-new computation paradigm, Edge Computing,
is surging in popularity. Meanwhile, Artificial Intelligence (AI) applications
are thriving with the breakthroughs in deep learning and the many improvements
in hardware architectures. Billions of data bytes, generated at the network
edge, put massive demands on data processing and structural optimization. Thus,
there exists a strong demand to integrate Edge Computing and AI, which gives
birth to Edge Intelligence. In this paper, we divide Edge Intelligence into AI
for edge (Intelligence-enabled Edge Computing) and AI on edge (Artificial
Intelligence on Edge). The former focuses on providing more optimal solutions
to key problems in Edge Computing with the help of popular and effective AI
technologies while the latter studies how to carry out the entire process of
building AI models, i.e., model training and inference, on the edge. This paper
provides insights into this new inter-disciplinary field from a broader
perspective. It discusses the core concepts and the research road-map, which
should provide the necessary background for potential future research
initiatives in Edge Intelligence.Comment: 13 pages, 3 figure
Trends and Challenges in Wireless Channel Modeling for an Evolving Radio Access
With the advent of 5G, standardization and research are currently defining
the next generation of the radio access. Considering the high constraints
imposed by the future standards, disruptive technologies such as Massive MIMO
and mmWave are being proposed. At the heart of this process are wireless
channel models that now need to cover a massive increase in design parameters,
a large variety of frequency bands, and heterogeneous deployments. This
tutorial describes how channel models address this new level of complexity and
which tools the community prepares to efficiently but accurately capture the
upcoming changes in radio access design. We analyze the main drivers behind
these new modeling tools, the challenges they pose, and survey the current
approaches to overcome them.Comment: 5 figures. To appear in IEEE Communication Magazin
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