2,552 research outputs found
Achieving Ultra-Low Latency in 5G Millimeter Wave Cellular Networks
The IMT 2020 requirements of 20 Gbps peak data rate and 1 millisecond latency
present significant engineering challenges for the design of 5G cellular
systems. Use of the millimeter wave (mmWave) bands above 10 GHz --- where vast
quantities of spectrum are available --- is a promising 5G candidate that may
be able to rise to the occasion.
However, while the mmWave bands can support massive peak data rates,
delivering these data rates on end-to-end service while maintaining reliability
and ultra-low latency performance will require rethinking all layers of the
protocol stack. This papers surveys some of the challenges and possible
solutions for delivering end-to-end, reliable, ultra-low latency services in
mmWave cellular systems in terms of the Medium Access Control (MAC) layer,
congestion control and core network architecture
Will 5G See its Blind Side? Evolving 5G for Universal Internet Access
Internet has shown itself to be a catalyst for economic growth and social
equity but its potency is thwarted by the fact that the Internet is off limits
for the vast majority of human beings. Mobile phones---the fastest growing
technology in the world that now reaches around 80\% of humanity---can enable
universal Internet access if it can resolve coverage problems that have
historically plagued previous cellular architectures (2G, 3G, and 4G). These
conventional architectures have not been able to sustain universal service
provisioning since these architectures depend on having enough users per cell
for their economic viability and thus are not well suited to rural areas (which
are by definition sparsely populated). The new generation of mobile cellular
technology (5G), currently in a formative phase and expected to be finalized
around 2020, is aimed at orders of magnitude performance enhancement. 5G offers
a clean slate to network designers and can be molded into an architecture also
amenable to universal Internet provisioning. Keeping in mind the great social
benefits of democratizing Internet and connectivity, we believe that the time
is ripe for emphasizing universal Internet provisioning as an important goal on
the 5G research agenda. In this paper, we investigate the opportunities and
challenges in utilizing 5G for global access to the Internet for all (GAIA). We
have also identified the major technical issues involved in a 5G-based GAIA
solution and have set up a future research agenda by defining open research
problems
Defending against Sybil Devices in Crowdsourced Mapping Services
Real-time crowdsourced maps such as Waze provide timely updates on traffic,
congestion, accidents and points of interest. In this paper, we demonstrate how
lack of strong location authentication allows creation of software-based {\em
Sybil devices} that expose crowdsourced map systems to a variety of security
and privacy attacks. Our experiments show that a single Sybil device with
limited resources can cause havoc on Waze, reporting false congestion and
accidents and automatically rerouting user traffic. More importantly, we
describe techniques to generate Sybil devices at scale, creating armies of
virtual vehicles capable of remotely tracking precise movements for large user
populations while avoiding detection. We propose a new approach to defend
against Sybil devices based on {\em co-location edges}, authenticated records
that attest to the one-time physical co-location of a pair of devices. Over
time, co-location edges combine to form large {\em proximity graphs} that
attest to physical interactions between devices, allowing scalable detection of
virtual vehicles. We demonstrate the efficacy of this approach using
large-scale simulations, and discuss how they can be used to dramatically
reduce the impact of attacks against crowdsourced mapping services.Comment: Measure and integratio
Wi-Fi Offload: Tragedy of the Commons or Land of Milk and Honey?
Fueled by its recent success in provisioning on-site wireless Internet
access, Wi-Fi is currently perceived as the best positioned technology for
pervasive mobile macro network offloading. However, the broad transitions of
multiple collocated operators towards this new paradigm may result in fierce
competition for the common unlicensed spectrum at hand. In this light, our
paper game-theoretically dissects market convergence scenarios by assessing the
competition between providers in terms of network performance, capacity
constraints, cost reductions, and revenue prospects. We will closely compare
the prospects and strategic positioning of fixed line operators offering Wi-Fi
services with respect to competing mobile network operators utilizing
unlicensed spectrum. Our results highlight important dependencies upon
inter-operator collaboration models, and more importantly, upon the ratio
between backhaul and Wi-Fi access bit-rates. Furthermore, our investigation of
medium- to long-term convergence scenarios indicates that a rethinking of
control measures targeting the large-scale monetization of unlicensed spectrum
may be required, as otherwise the used free bands may become subject to
tragedy-of-commons type of problems.Comment: Workshop on Spectrum Sharing Strategies for Wireless Broadband
Services, IEEE PIMRC'13, to appear 201
Economic Policy Analysis and the Internet: Coming to Terms with a Telecommunications Anomaly
The significant set of public policy issues for economic analysis that arise from the tensions between the âspecial benefitsâ of the Internet as a platform for innovation, and the drawbacks of the âanomalousâ features of the Internet viewed as simply one among the array of telecommunications systems, is the focus of discussion in this chapter. Economists concerned with industrial organization and regulation (including antitrust and merger law) initially found new scope for application of their expertise in conventional policy analyses of the Internetâs interactions with other segments of the telecommunications sector (broadcast and cable television, radio and telephone), and emphasized the potential congestion problems posed by user anonymity and flat rate pricing. Policy issues of a more dynamic kind have subsequently come to the fore. These involve classic tradeoffs between greater efficiency and producer and consumer surpluses today, and a potential for more innovation in Web-based products and service in the future. Many such tradeoffs involve choices such as that between policies that would preserve the original âend-to-endâ design of the original Internet architecture, and those that would be more encouraging of market-driven deployment of new technologies that afforded ISPs with greater market power the opportunity to offer (and extract greater profits from) restricted-Web services that consumers valued highly, such as secure and private VOIP.public policy, telecommunications, Web-based products, user anonymity
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