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Network routing system, method, and computer program product
A method, system, or computer program product to enhance the performance of multi-hop cellular networks or other wireless networks is provided. A wireless device (e.g., cellular telephone) is able to communicate with a base-station in a cell of the cellular network over a non-cellular interface via another wireless device in the cell through the use of multi-hopping. By enabling wireless devices to communicate with a base station in such a manner, the effective coverage area of the cellular network is expanded and the effective capacity of the cellular network is improved. Distributed routing, device management, adaptive scheduling, and distributed algorithms can be used to enhance the overall performance of multi-hop cellular networks.Board of Regents, University of Texas Syste
Performance metrics and routing in vehicular ad hoc networks
The aim of this thesis is to propose a method for enhancing the performance of Vehicular Ad hoc
Networks (VANETs). The focus is on a routing protocol where performance metrics are used to
inform the routing decisions made. The thesis begins by analysing routing protocols in a random
mobility scenario with a wide range of node densities. A Cellular Automata algorithm is
subsequently applied in order to create a mobility model of a highway, and wide range of density
and transmission range are tested. Performance metrics are introduced to assist the prediction of
likely route failure. The Good Link Availability (GLA) and Good Route Availability (GRA)
metrics are proposed which can be used for a pre-emptive action that has the potential to give
better performance. The implementation framework for this method using the AODV routing
protocol is also discussed. The main outcomes of this research can be summarised as identifying
and formulating methods for pre-emptive actions using a Cellular Automata with NS-2 to
simulate VANETs, and the implementation method within the AODV routing protocol
cISP: A Speed-of-Light Internet Service Provider
Low latency is a requirement for a variety of interactive network
applications. The Internet, however, is not optimized for latency. We thus
explore the design of cost-effective wide-area networks that move data over
paths very close to great-circle paths, at speeds very close to the speed of
light in vacuum. Our cISP design augments the Internet's fiber with free-space
wireless connectivity. cISP addresses the fundamental challenge of
simultaneously providing low latency and scalable bandwidth, while accounting
for numerous practical factors ranging from transmission tower availability to
packet queuing. We show that instantiations of cISP across the contiguous
United States and Europe would achieve mean latencies within 5% of that
achievable using great-circle paths at the speed of light, over medium and long
distances. Further, we estimate that the economic value from such networks
would substantially exceed their expense
A Pragmatic View of MANET Performance Evaluation and Design of a Prototype MAC Level Routing Algorithm
Our goal in this research is to investigate and determine how to best support a challenging mobile wireless network based in a military operational environment. Since routing protocols used in mobile ad hoc networks (MANET) must adapt to frequent or continual changes of topology, while simultaneously limiting the impact of tracking these changes on wireless resources, we focused our initial research on improving the efficiency of route discovery. We proposed and designed a new MAC layer routing protocol that pursues reduced routing overhead, greater interaction of network protocol layers and passive neighbor/path discovery. This algorithm, called Virtual MAC Tag Switching (VMTS), evolved as we implemented a prototype in the ns-2 network simulator and conducted simulation analysis of existing protocols: DSDV, DSR and AODV. Upon analyzing the performance of existing routing protocols using pragmatic metrics not applied in any MANET literature it was found that current MANET models produce unsatisfactory performance. Subsequent analysis of transport layer protocol behaviors pinpointed the causes that undermine the performance of the existing protocols and would have thwarted VMTS as well
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