5 research outputs found
Energy Evaluation of PMCMTP for Large-Scale Wireless Sensor Networks
10International audiencePMCMTP is a Prioritized Multi-Channel Multi- Time slot MAC protocol that the authors have proposed for allowing to simultaneous use of several frequency channels. This protocol is designed for UWB of IEEE802.15.4a but it can also be used over IEEE802.15.4. In this paper, we design and implement a testbed of this protocol to demonstrate its practical implementability. Due to the unavailability of UWB transceiver, the testbed has been performed using classic 2.4GHz WSN transceivers. To reduce the complexity of resource sharing, the global network is composed of a set of Personal Area Networks (PANs) or cells. So, the PMCMTPs experiments are performed for a single PAN and two PANs
Estratégias de design de camada intermédia e cooperativa para redes sem fios energeticamente eficientes
Doutoramento conjunto MAP-i em InformĂĄticaThe promise of a truly mobile experience is to have the freedom to roam
around anywhere and not be bound to a single location. However, the energy
required to keep mobile devices connected to the network over extended
periods of time quickly dissipates. In fact, energy is a critical resource in
the design of wireless networks since wireless devices are usually powered by
batteries. Furthermore, multi-standard mobile devices are allowing users to
enjoy higher data rates with ubiquitous connectivity. However, the bene ts
gained from multiple interfaces come at a cost in terms of energy consumption
having profound e ect on the mobile battery lifetime and standby
time. This concern is rea rmed by the fact that battery lifetime is one of
the top reasons why consumers are deterred from using advanced multimedia
services on their mobile on a frequent basis. In order to secure market
penetration for next generation services energy e ciency needs to be placed
at the forefront of system design. However, despite recent e orts, energy
compliant features in legacy technologies are still in its infancy, and new
disruptive architectures coupled with interdisciplinary design approaches are
required in order to not only promote the energy gain within a single protocol
layer, but to enhance the energy gain from a holistic perspective. A
promising approach is cooperative smart systems, that in addition to exploiting
context information, are entities that are able to form a coalition
and cooperate in order to achieve a common goal. Migrating from this baseline,
this thesis investigates how these technology paradigm can be applied
towards reducing the energy consumption in mobile networks. In addition,
we introduce an additional energy saving dimension by adopting an interlayer
design so that protocol layers are designed to work in synergy with
the host system, rather than independently, for harnessing energy. In this
work, we exploit context information, cooperation and inter-layer design for
developing new energy e cient and technology agnostic building blocks for
mobile networks. These technology enablers include energy e cient node
discovery and short-range cooperation for energy saving in mobile handsets,
complemented by energy-aware smart scheduling for promoting energy saving
on the network side. Analytical and simulations results were obtained,
and veri ed in the lab on a real hardware testbed. Results have shown that
up to 50% energy saving could be obtained.A promessa de uma experiĂȘncia realmente mĂłvel Ă© de ter a liberdade de deambular por qualquer sĂtio e nĂŁo estar preso a um Ășnico local. No entanto, a energia requerida para manter dispositivos mĂłveis conectados Ă rede, num perĂodo extenso de tempo, o mesmo rapidamente se dissipa. Na realidade, a energia Ă© um recurso crĂtico no design de redes sem fios, uma vez que esses dispositivos sĂŁo alimentados por baterias. Para alĂ©m disso, dispositivos mĂłveis multi-standard permitem que os utilizadores desfrutem
de elevadas taxas de dados com conectividade omnipresente. No entanto, as vantagens adquiridas pelas mĂșltiplas interfaces, imputa uma despesa, sendo essa um consumo maior de energia, numa era onde os dispositivos mĂłveis tĂȘm de ser energicamente complacentes. Esta preocupação Ă© reafirmada pelo facto de que a vida da bateria Ă© uma das principais razĂ”es que impede os utilizadores de usufruir e utilizar de serviços de multimĂ©dia mais avançados nos seus dispositivos, numa base frequente. De forma a assegurar a entrada no mercado para serviços da prĂłxima geração, eficiĂȘncia energĂ©tica tem de ser colocada na vanguarda do design de sistemas. No entanto, apesar de esforços recentes, funcionalidades que cumpram os requisitos energĂ©ticos em tecnologias "legacy" ainda estĂŁo nos seus primĂłrdios e novas abordagens disruptivas sĂŁo requeridas, juntamente com abordagem de design interdisciplinar, de forma a aproveitar a poupança energĂ©tica das diversas camadas protocolares. Uma bordagem promissora sĂŁo os sistemas de cooperação inteligente,
que exploram nĂŁo sĂŁo contexto da informação, mas tambĂ©m as entidades que sĂŁo igualmente capazes de formar uma coligação e cooperam de forma a atingir um objectivo comum. Migrar a partir destas referĂȘncias, esta tese investiga como Ă© que este paradigma tecnolĂłgico pode ser aplicado para reduzir a potĂȘncia e consumo de energia em redes mĂłveis. Para alĂ©m disso, introduzimos uma dimensĂŁo de poupança energĂ©tica adicional, para adopção de design de camadas intermĂ©dias, de forma a que as camadas de protocolos sejam concebidas para trabalhar em sinergia com o sistema anfitriĂŁo, ao invĂ©s de independentemente, para aproveitamento de energia.
Neste trabalho, nós exploramos o contexto da informação, cooperação e design de camadas intermédias para desenvolver blocos de construção energicamente eficientes e tecnologias agnósticas para redes móveis. Estes habilitadores (enablers) tecnológicos incluem um nó de descoberta de energia eficiente e cooperação de curto alcance para poupança energética em aparelhos móveis, complementado com agendamento inteligente, energicamente consciente, de forma a promover a poupança de energia do lado da rede. Analiticamente e simultaneamente, foram obtidos resultados e verificados em laboratório, num modelo de hardware protótipo. Resultados demonstram que pode ser obtido uma poupança energética acima dos 50%
Smart PIN: performance and cost-oriented context-aware personal information network
The next generation of networks will involve interconnection of heterogeneous individual
networks such as WPAN, WLAN, WMAN and Cellular network, adopting the IP as common infrastructural protocol and providing virtually always-connected network. Furthermore,
there are many devices which enable easy acquisition and storage of information as pictures, movies, emails, etc. Therefore, the information overload and divergent contentâs
characteristics make it difficult for users to handle their data in manual way. Consequently, there is a need for personalised automatic services which would enable data exchange across heterogeneous network and devices. To support these personalised services, user centric approaches
for data delivery across the heterogeneous network are also required.
In this context, this thesis proposes Smart PIN - a novel performance and cost-oriented context-aware Personal Information Network. Smart PIN's architecture is detailed including its network, service and management components. Within the service component, two novel schemes for efficient delivery of context and content data are proposed:
Multimedia Data Replication Scheme (MDRS) and Quality-oriented Algorithm for Multiple-source Multimedia Delivery (QAMMD).
MDRS supports efficient data accessibility among distributed devices using data replication which is based on a utility function and a minimum data set. QAMMD employs a buffer underflow avoidance scheme for streaming, which achieves high multimedia quality without content adaptation to network conditions. Simulation models for MDRS and
QAMMD were built which are based on various heterogeneous network scenarios. Additionally a multiple-source streaming based on QAMMS was implemented as a prototype and tested in an emulated network environment. Comparative tests show that MDRS and QAMMD perform significantly better than other approaches
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Application priority framework for fixed mobile converged communication networks
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The current prospects in wired and wireless access networks, it is becoming increasingly important to address potential convergence in order to offer integrated broadband services. These systems will need to offer higher data transmission capacities and long battery life, which is the catalyst for an everincreasing variety of air interface technologies targeting local area to wide area connectivity. Current integrated industrial networks do not offer application aware context delivery and enhanced services for optimised networks. Application aware services provide value-added functionality to business applications by capturing, integrating, and consolidating intelligence about users and their endpoint devices from various points in the network. This thesis mainly intends to resolve the issues related to ubiquitous application aware service, fair allocation of radio access, reduced energy consumption and improved capacity. A technique that measures and evaluates the data rate demand to reduce application response time and queuing delay for multi radio interfaces is proposed. The technique overcomes the challenges of network integration, requiring no user intervention, saving battery life and selecting the radio access connection for the application requested by the end user. This study is split in two parts. The first contribution identifies some constraints of the services towards the application layer in terms of e.g. data rate and signal strength. The objectives are achieved by application controlled handover (ACH) mechanism in order to maintain acceptable data rate for real-time application services. It also looks into the impact of the radio link on the application and identifies elements and parameters like wireless link quality and handover that will influence the application type. It also identifies some enhanced traditional mechanisms such as distance controlled multihop and mesh topology required in order to support energy efficient multimedia applications. The second contribution unfolds an intelligent application priority assignment mechanism (IAPAM) for medical applications using wireless sensor networks. IAPAM proposes and evaluates a technique based on prioritising multiple virtual queues for the critical nature of medical data to improve instant transmission. Various mobility patterns (directed, controlled and random waypoint) has been investigated and compared by simulating IAPAM enabled mobile BWSN. The following topics have been studied, modelled, simulated and discussed in this thesis: 1. Application Controlled Handover (ACH) for multi radios over fibre 2. Power Controlled Scheme for mesh multi radios over fibre using ACH 3. IAPAM for Biomedical Wireless Sensor Networks (BWSN) and impact of mobility over IAPAM enabled BWSN. Extensive simulation studies are performed to analyze and to evaluate the proposed techniques. Simulation results demonstrate significant improvements in multi radios over fibre performance in terms of application response delay and power consumption by upto 75% and 15 % respectively, reduction in traffic loss by upto 53% and reduction in delay for real time application by more than 25% in some cases