333 research outputs found
Computational Public Safety in Emergency Management Communications
Communications are very important in any situation but in emergency management it is imperative that the communications be reliable and responsive to the evolving situation. In emergency management there are many different types of networks with different objectives. It is of immense value to have the ability to seamlessly integrate other networks and computing resources into one interconnected heterogeneous network. The entire management team should be able to access any of the individual networks and their resources. In this paper we discuss various wireless network communication options in the context of their viability for use in emergency management. We analyze various technical aspects such as propagation delay, packet delivery ratio, and transmission rates. In addition the environmental conditions that impair communications are discussed. All experiments we conducted took place in a setting that was real, using real equipment that was physically situated in settings that can be expected in urban disaster settings—our results are not simulations. They were performed in cooperation with the Ontario Provincial Police, Provincial Emergency Response Tea
Wireless Mesh Network Performance for Urban Search and Rescue Missions
In this paper we demonstrate that the Canine Pose Estimation (CPE) system can
provide a reliable estimate for some poses and when coupled with effective
wireless transmission over a mesh network. Pose estimates are time sensitive,
thus it is important that pose data arrives at its destination quickly.
Propagation delay and packet delivery ratio measuring algorithms were developed
and used to appraise Wireless Mesh Network (WMN) performance as a means of
carriage for this time-critical data. The experiments were conducted in the
rooms of a building where the radio characteristics closely resembled those of
a partially collapsed building-a typical US&R environment. This paper presents
the results of the experiments, which demonstrate that it is possible to
receive the canine pose estimation data in realtime although accuracy of the
results depend on the network size and the deployment environment.Comment: 19 Pages, IJCNC Journa
Wireless Mesh Network Performance for Urban Search and Rescue Missions
in this paper we demonstrate that the Canine Pose Estimation (CPE) system can provide a reliable estimate for some poses and when coupled with effective wireless transmission over a mesh network. Pose estimates are time sensitive, thus it is important that pose data arrives at its destination quickly. Propagation delay and packet delivery ratio measuring algorithms were developed and used to appraise Wireless Mesh Network (WMN) performance as a means of carriage for this time-critical data. The experiments were conducted in the rooms of a building where the radio characteristics closely resembled those of a partially collapsed building-a typical US&R environment. This paper presents the results of the experiments, which demonstrate that it is possible to receive the canine pose estimation data in realtime although accuracy of the results depend on the network size and the deployment environment
Self-organizing Network Optimization via Placement of Additional Nodes
Das Hauptforschungsgebiet des Graduiertenkollegs "International Graduate
School on Mobile Communication" (GS Mobicom) der Technischen Universität
Ilmenau ist die Kommunikation in Katastrophenszenarien. Wegen eines
Desasters oder einer Katastrophe können die terrestrischen Elementen der
Infrastruktur eines Kommunikationsnetzwerks beschädigt oder komplett
zerstört werden. Dennoch spielen verfügbare Kommunikationsnetze eine sehr
wichtige Rolle während der Rettungsmaßnahmen, besonders für die
Koordinierung der Rettungstruppen und fĂĽr die Kommunikation zwischen ihren
Mitgliedern. Ein solcher Service kann durch ein mobiles Ad-Hoc-Netzwerk
(MANET) zur VerfĂĽgung gestellt werden. Ein typisches Problem der MANETs
ist Netzwerkpartitionierung, welche zur Isolation von verschiedenen
Knotengruppen führt. Eine mögliche Lösung dieses Problems ist die
Positionierung von zusätzlichen Knoten, welche die Verbindung zwischen den
isolierten Partitionen wiederherstellen können. Hauptziele dieser Arbeit
sind die Recherche und die Entwicklung von Algorithmen und Methoden zur
Positionierung der zusätzlichen Knoten. Der Fokus der Recherche liegt auf
Untersuchung der verteilten Algorithmen zur Bestimmung der Positionen fĂĽr
die zusätzlichen Knoten. Die verteilten Algorithmen benutzen nur die
Information, welche in einer lokalen Umgebung eines Knotens verfĂĽgbar ist,
und dadurch entsteht ein selbstorganisierendes System. Jedoch wird das
gesamte Netzwerk hier vor allem innerhalb eines ganz speziellen Szenarios -
Katastrophenszenario - betrachtet. In einer solchen Situation kann die
Information ĂĽber die Topologie des zu reparierenden Netzwerks im Voraus
erfasst werden und soll, natĂĽrlich, fĂĽr die Wiederherstellung mitbenutzt
werden. Dank der eventuell verfügbaren zusätzlichen Information können
die Positionen für die zusätzlichen Knoten genauer ermittelt werden. Die
Arbeit umfasst eine Beschreibung, Implementierungsdetails und eine
Evaluierung eines selbstorganisierendes Systems, welche die
Netzwerkwiederherstellung in beiden Szenarien ermöglicht.The main research area of the International Graduate School on Mobile
Communication (GS Mobicom) at Ilmenau University of Technology is
communication in disaster scenarios. Due to a disaster or an accident, the
network infrastructure can be damaged or even completely destroyed.
However, available communication networks play a vital role during the
rescue activities especially for the coordination of the rescue teams and
for the communication between their members. Such a communication service
can be provided by a Mobile Ad-Hoc Network (MANET). One of the typical
problems of a MANET is network partitioning, when separate groups of nodes
become isolated from each other. One possible solution for this problem is
the placement of additional nodes in order to reconstruct the communication
links between isolated network partitions. The primary goal of this work is
the research and development of algorithms and methods for the placement of
additional nodes. The focus of this research lies on the investigation of
distributed algorithms for the placement of additional nodes, which use
only the information from the nodes’ local environment and thus form a
self-organizing system. However, during the usage specifics of the system
in a disaster scenario, global information about the topology of the
network to be recovered can be known or collected in advance. In this case,
it is of course reasonable to use this information in order to calculate
the placement positions more precisely. The work provides the description,
the implementation details and the evaluation of a self-organizing system
which is able to recover from network partitioning in both situations
Constructing Dynamic Ad-hoc Emergency Networks using Software-Defined Wireless Mesh Networks
Natural disasters and other emergency situations have the potential to destroy a whole network infrastructure needed for communication critical to emergency rescue, evacuation, and initial rehabilitation. Hence, the research community has begun to focus attention on rapid network reconstruction in such emergencies; however, research has tried to create or improve emergency response systems using traditional radio and satellite communications, which face high operation costs and frequent disruptions. This thesis proposes a centralized monitoring and control system to reconstruct ad-hoc networks in emergencies by using software-defined wireless mesh networks (SDWMN). The proposed framework utilizes wireless mesh networks and software-defined networking to provide real-time network monitoring services to restore Internet access in a targeted disaster zone. It dispatches mobile devices including unmanned aerial vehicles and self-driving cars to the most efficient location aggregation to recover impaired network connections by using a new GPS position finder (GPS-PF) algorithm. The algorithm is based on density-based spatial clustering that calculates the best position to deploy one of the mobile devices. The proposed system is evaluated using the common open research emulator to demonstrate its efficiency and high accessibility in emergency situations. The results obtained from the evaluation show that the performance of the emergency communication system is improved considerably with the incorporation of the framework
Concept and design of the hybrid distributed embedded systems testbed
Wireless mesh networks are an emerging and versatile communication technology.
The most common application of these networks is to provide access of any
number of users to the world wide Internet. They can be set up by Internet
service providers or even individuals joined in communities. Due to the
wireless medium that is shared by all participants, effects like short-time
fading, or the multi-hop property of the network topology many issues are
still in the focus of research. Testbeds are a powerful tool to study wireless
mesh networks as close as possible to real world application scenarios. In
this technical report we describe the design, architecture, and implementation
of our work-in-progress wireless testbed at Freie Universität Berlin
consisting of 100 mesh routers that span multiple buildings. The testbed is
hybrid as it combines wireless mesh network routers with a wireless sensor
network
ADMP: an adaptive multicast routing protocol for mobile ad hoc networks
We present ADMP, the adaptive mesh-based multicast routing protocol, in which nodes are able to independently tune the amount of redundancy used to transmit data packets with the goal of improving the overall packet delivery ratio while keeping the retransmission overhead as low as possible. ADMP is based on a novel distributed algorithm for computing connected dominating sets. ADMP uses a single type of control packet, called multicast announcement, which is used to build the meshes of multicast groups, elect the core of each mesh and obtain two-hop neighborhood information. Using detailed simulations for different scenarios, we show that ADMP achieves similar or better reliability than two mesh-based multicast protocols that are very resilient (ODMRP and PUMA) while inducing low packet retransmission overhead.1st IFIP International Conference on Ad-Hoc NetWorkingRed de Universidades con Carreras en Informática (RedUNCI
Design and evaluation of a self-configuring wireless mesh network architecture
Wireless network connectivity plays an increasingly important role in supporting our everyday private and professional lives. For over three decades, self-organizing wireless multi-hop ad-hoc networks have been investigated as a decentralized replacement for the traditional forms of wireless networks that rely on a wired infrastructure. However, despite the tremendous efforts of the international wireless research community and widespread availability of devices that are able to support these networks, wireless ad-hoc networks are hardly ever used.
In this work, the reasons behind this discrepancy are investigated. It is found that several basic theoretical assumptions on ad-hoc networks prove to be wrong when solutions are deployed in reality, and that several basic functionalities are still missing. It is argued that a hierarchical wireless mesh network architecture, in which specialized, multi-interfaced mesh nodes form a reliable multi-hop wireless backbone for the less capable end-user clients is an essential step in bringing the ad-hoc networking concept one step closer to reality.
Therefore, in a second part of this work, algorithms increasing the reliability and supporting the deployment and management of these wireless mesh networks are developed, implemented and evaluated, while keeping the observed limitations and practical considerations in mind. Furthermore, the feasibility of the algorithms is verified by experiment.
The performance analysis of these protocols and the ability to deploy the developed algorithms on current generation off-the-shelf hardware indicates the successfulness of the followed research approach, which combines theoretical considerations with practical implementations and observations. However, it was found that there are also many pitfalls to using real-life implementation as a research technique. Therefore, in the last part of this work, a methodology for wireless network research using real-life implementation is developed, allowing researchers to generate more reliable protocols and performance analysis results with less effort
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