4,524 research outputs found
HopScotch - a low-power renewable energy base station network for rural broadband access
The provision of adequate broadband access to communities in sparsely populated rural areas has in the past been severely restricted. In this paper, we present a wireless broadband access test bed running in the Scottish Highlands and Islands which is based on a relay network of low-power base stations. Base stations are powered by a combination of renewable sources creating a low cost and scalable solution suitable for community ownership. The use of the 5~GHz bands allows the network to offer large data rates and the testing of ultra high frequency ``white space'' bands allow expansive coverage whilst reducing the number of base stations or required transmission power. We argue that the reliance on renewable power and the intelligent use of frequency bands makes this approach an economic green radio technology which can address the problem of rural broadband access
Future broadband access network challenges
Copyright @ 2010 IEEEThe optical and wireless communication systems convergence will activate the potential capacity of photonic technology for providing the expected growth in interactive video, voice communication and data traffic services that are cost effective and a green communication service. The last decade growth of the broadband internet projects the number of active users will grow to over 2 billion globally by the end of 2014. Enabling the abandoned capacity of photonic signal processing is the promising solution for seamless transportation of the future consumer traffic demand. In this paper, the future traffic growth of the internet, wireless worldwide subscribers, and the end-users during the last and next decades is investigated. The challenges of the traditional access networks and Radio over Fiber solution are presented
Cross-layer design of multi-hop wireless networks
MULTI -hop wireless networks are usually defined as a collection of nodes
equipped with radio transmitters, which not only have the capability to
communicate each other in a multi-hop fashion, but also to route each othersâ data
packets. The distributed nature of such networks makes them suitable for a variety of
applications where there are no assumed reliable central entities, or controllers, and
may significantly improve the scalability issues of conventional single-hop wireless
networks.
This Ph.D. dissertation mainly investigates two aspects of the research issues
related to the efficient multi-hop wireless networks design, namely: (a) network
protocols and (b) network management, both in cross-layer design paradigms to
ensure the notion of service quality, such as quality of service (QoS) in wireless mesh
networks (WMNs) for backhaul applications and quality of information (QoI) in
wireless sensor networks (WSNs) for sensing tasks. Throughout the presentation of
this Ph.D. dissertation, different network settings are used as illustrative examples,
however the proposed algorithms, methodologies, protocols, and models are not
restricted in the considered networks, but rather have wide applicability.
First, this dissertation proposes a cross-layer design framework integrating
a distributed proportional-fair scheduler and a QoS routing algorithm, while using
WMNs as an illustrative example. The proposed approach has significant performance
gain compared with other network protocols. Second, this dissertation proposes
a generic admission control methodology for any packet network, wired and
wireless, by modeling the network as a black box, and using a generic mathematical
0. Abstract 3
function and Taylor expansion to capture the admission impact. Third, this dissertation
further enhances the previous designs by proposing a negotiation process,
to bridge the applicationsâ service quality demands and the resource management,
while using WSNs as an illustrative example. This approach allows the negotiation
among different service classes and WSN resource allocations to reach the optimal
operational status. Finally, the guarantees of the service quality are extended to
the environment of multiple, disconnected, mobile subnetworks, where the question
of how to maintain communications using dynamically controlled, unmanned data
ferries is investigated
Governing the Networks of the Information Society. Prospects and limits of policy in a complex technical system
This paper examines the prospects and limits of policies towards information and communications technologies (ICTs). The co-evolution of technological, economic, and political factors that has affected the information network infrastructure during the past three decades has transformed it from a relatively closed to more open system. As a consequence, the degree of complexity of the ICT infrastructure has increased with far-reaching implications for its governance. Paradoxically, policy was better able to control important performance characteristics, such as prices or investment levels, during the past monopoly era. However, the ability to control came at the high price of the inefficiencies associated with monopoly organization. In the present more competitive framework, many feasible policy instruments only work indirectly. Sector performance is an emergent property resulting from decentralized decisions in markets. It is influenced but not fully determined by policy choices. These changes need to be recognized more explicitly in the theoretical foundations, the formation and the implementation of policy. Applying concepts from the theory of complex evolving systems, the paper develops lessons for the design of effective information and communications policy.Information and communication technology, governance, complexity, incomplete information, institutions, feasible policy
Broadband: a solution to rural e-learning?
Rural and remote learners are disadvantaged even with online provision due to poor connections. Broadband offers a potential solution. This paper looks at the initial results of a project to install broadband services in the Western Isles of Scotland. It focuses on the educational potential of broadband and the design implications for online courses. It also considers more informal kinds of learning that broadband facilitates in rural areas
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