27 research outputs found
Service oriented networking for multimedia applications in broadband wireless networks
Extensive efforts have been focused on deploying broadband wireless networks. Providing mobile users with high speed network connectivity will let them run various multimedia applications on their wireless devices. In order to successfully deploy and operate broadband wireless networks, it is crucial to design efficient methods for supporting various services and applications in broadband wireless networks. Moreover, the existing access-oriented networking solutions are not able to fully address all the issues of supporting various applications with different quality of service requirements. Thus, service-oriented networking has been recently proposed and has gained much attention.
This dissertation discusses the challenges and possible solutions for supporting multimedia applications in broadband wireless networks. The service requirements of different multimedia applications such as video streaming and Voice over IP (VoIP) are studied and some novel service-oriented networking solutions for supporting these applications in broadband wireless networks are proposed. The performance of these solutions is examined in WiMAX networks which are the promising technology for broadband wireless access in the near future. WiMAX networks are based on the IEEE 802.16 standards which have defined different Quality of Service (QoS) classes to support a broad range of applications with varying service requirements to mobile and stationary users.
The growth of multimedia traffic that requires special quality of service from the network will impose new constraints on network designers who should wisely allocate the limited resources to users based on their required quality of service. An efficient resource management and network design depends upon gaining accurate information about the traffic profile of user applications. In this dissertation, the access level traffic profile of VoIP applications are studied first, and then a realistic distribution model for VoIP traffic is proposed. Based on this model, an algorithm to allocate resources for VoIP applications in WiMAX networks is investigated. Later, the challenges and possible solutions for transmitting MPEG video streams in wireless networks are discussed. The MPEG traffic model adopted by the WiMAX Forum is introduced and different application-oriented solutions for enhancing the performance of wireless networks with respect to MPEG video streaming applications are explained. An analytical framework to verify the performance of the proposed solutions is discoursed, and it is shown that the proposed solutions will improve the efficiency of VoIP applications and the quality of streaming applications over wireless networks. Finally, conclusions are drawn and future works are discussed
Hybrid wireless broadband networks
A hybrid system is an integration of two or more different systems, particularly in this thesis referring to wireless broadband networks. However, to provide end-to-end quality of service (QoS) in a hybrid system is a challenging task due to different protocol in each system. In this thesis, we aim to improve the overall performance of hybrid networks in a disaster management by addressing the challenges as well as the problems in a homogeneous network. Such an approach allows more efficient multi-parameter optimization and significant improvements in the overall system performance. More specifically, we introduce two novel algorithms. The first is the novel end-to-end QoS algorithm for hybrid wireless broadband networks. We proposed the end-to-end QoS maps based on particular chosen parameters and analyse the simulation results. The QoS maps are applied to a few scenarios, and the performance evaluation of the constructed network is presented. Based on the results obtained by software simulation tools, the performance validation shows that the hybrid network has specific advantages and constraints in terms of number of users, preference, coverage and applications. The second algorithm presented is the novel in users’ application algorithm, the purpose of which is to optimize bandwidth for first responders applied in the PPDR project under grant agreement EU FP7 SEC PPDR-TC. This algorithm is responsible for incorporating more users and different levels of background load to a hybrid network. The proposed method analyses both positive and negative outcomes based on the results obtained. This algorithm has been presented in the PPDR project
Suporte de mobilidade em redes WIMAX
O desenvolvimento crescente da Internet, com novos serviços e
aplicações que requerem elevadas exigências a nível de qualidade de
serviço, como por exemplo, o VoIP e IPTV, a crescente necessidade de
um utilizador estar sempre contactável em qualquer sítio e a qualquer
momento, torna necessária a integração actual da Internet com as redes
móveis da próxima geração.
A tecnologia IEEE 802.16 surge como uma tecnologia de banda larga
sem fios que pode ter um papel fundamental num ambiente de próxima
geração. Devido aos seus baixos custos de instalação e à possibilidade de
chegar facilmente a zonas rurais ou a zonas de difícil acesso, torna-se um
sério candidato para suprir as necessidades dos utilizadores.
A necessidade de mobilidade pelo utilizador, para aceder a diversos
serviços em diferentes sítios ou ser identificado remotamente para a
posterior recepção de informação também é um desejo futuro.
O protocolo IEEE 802.21 surge como um meio que providencia a
optimização de handover entre diferentes tecnologias de acesso, quer
sejam elas WiFi, WiMAX, 3GGP ou 3GPP2, no sentido de proporcionar
ao utilizador a utilização de diferentes serviços de uma forma
transparente à tecnologia de acesso, quando em situações de mobilidade.
Esta dissertação apresenta a arquitectura desenvolvida para proporcionar
a correcta avaliação da atribuição de QoS e mobilidade transparente,
num ambiente real de próxima geração. Serão também efectuados testes
com o equipamento WiMAX disponível, no sentido de mostrar o seu
correcto comportamento na atribuição de QoS fim-a-fim em cenários
ponto-a-ponto e ponto-a-multiponto com serviços com características de
tempo real. A integração do software da primeira fase do projecto
WEIRD e o seu correcto comportamento em ambientes de atribuição de
QoS também vai ser estudado. A implementação dos diferentes módulos,
em especial a implementação da unidade central da arquitectura de IEEE
802.21 (MIHF), vai ser descrita, no sentido de avaliar o desempenho do
WiMAX e do protocolo IEEE 802.21 numa rede real no âmbito da
segunda fase do projecto WEIRD. Os resultados obtidos demonstram
que a arquitectura desenvolvida consegue fornecer QoS fim-a-fim com
suporte de mobilidade entre redes heterogéneas.
ABSTRACT: The growing development of the Internet, with new services and
applications that require a high level of quality of service, such as, VoIP
and IPTV, the increasing need for a user to be always reachable
anywhere and at anytime, motivates the integration of current Internet
with the next generation of mobile networks.
The IEEE 802.16 technology emerges as a technology for broadband
wireless access that may have a key role in a next generation
environment. Due to its low costs of installation and its ability to easily
reach rural areas or areas with difficult access, it becomes a serious
candidate to supply the needs of users.
The mobility’s necessity by the user, to access to several services in
different locations or be identified remotely for subsequent receipt of
information, is also a future desire.
The IEEE 802.21 protocol provides the optimization of handover
between heterogeneous networks, such as WiFi, WiMAX, 3GGP or
3GPP2, to offer the user different services in a transparent manner to his
access technology, when in situations of mobility.
This Thesis presents the architecture developed to provide the correct
integration of QoS and seamless mobility, in a real next generation
environment. It will also present tests carries out with the available
WiMAX equipment, to show its correct behaviour in the allocation of
end-to-end QoS in point-to-point and point-to-multipoint scenarios with
real-time services. The integration of software from the first phase of the
WEIRD project and its correct behaviour in environments of QoS
allocation will also be studied. The implementation of the various
modules, in particular the implementation of the central unit of IEEE
802.21 architecture (MIHF), will be described, to evaluate the
performance of WiMAX and IEEE 802.21 protocol in a real network
provided by the second phase of the WEIRD project. The obtained
results show that the developed architecture is able to provide end-toend
QoS with seamless mobility support over heterogeneous networks
Connection admission control and packet scheduling for IEEE 802.16 networks
Includes bibliographical references.The IEEE 802.16 standard introduced as one of the Wireless Metropolitan Area Networks (WMAN) for Broadband Wireless Access (BWA) which is known as Worldwide Interoperability for Microwave Access (WiMAX), provides a solution of broadband connectivity to areas where wired infrastructure is economically and technically infeasible. Apart from the advantage of having high speeds and low costs, IEEE 802.16 has the capability to simultaneously support various service types with required QoS characteristics. ... While IEEE 802.16 standard defines medium access control (MAC) and physical (PHY) layers specification, admission control and packet scheduling mechanisms which are important elements of QoS provisioning are left to vendors to design and implement for service differentiation and QoS support
Qualidade de serviço em redes de acesso IEEE 802.16
Mestrado em Engenharia Electrónica e TelecomunicaçõesA procura de serviços e de aplicações com elevadas exigências de largura de
banda, e a vontade crescente para aceder a este tipo de serviços em qualquer
lugar, torna necessária a integração da Internet actual com as redes móveis de
próxima geração. No entanto, existirão sempre àreas remotas onde o acesso à
Internet, e nomeadamente a serviços de banda larga, será difícil de conseguir.
O protocolo IEEE 802.16 é uma tecnologia de banda larga sem fios que pode
ser usada neste tipo de cenários. Esta dissertação apresenta uma arquitectura
de rede capaz de suportar serviços de tempo real com integração de QoS em
ambientes IPv6 através da utilização de redes IEEE 802.16. Nomeadamente, a
arquitectura definida suporta o acesso dinâmico e rápido por parte dos
terminais móveis aos serviços de rede, tal como reservas e modificações
dinâmicas de serviços de tempo real, característica essencial para o suporte
de alta mobilidade. Para além disto, a solução proposta fornece também
suporte IPv6 e diferenciação de serviços direccionados para o mesmo terminal
móvel.
Esta dissertação apresenta a arquitectura desenvolvida, os módulos
necessários para a integração da tecnologia IEEE 802.16 num ambiente de
próxima geração, a implementação desses módulos para a construção de uma
rede real, e testes para avaliar o desempenho da rede em termos de QoS num
ambiente de rede de acesso mista, composta por IEEE 802.16 e IEEE 802.11.
São também efectuados testes de mobilidade para avaliar o desempenho da
solução descrita neste tipo de ambientes. Os resultados obtidos com a
arquitectura desenvolvida mostram que a arquitectura pode fornecer QoS fima-
fim sobre a concatenação de redes metropolitanas e locais, com suporte de
mobilidade.The growing demand of high bandwidth services and applications, and the
increasing will of access to these services anywhere, is motivating the
requirement to integrate the current Internet with the future mobile networks.
However, there will always be remote areas where Internet access will be
difficult to achieve. The IEEE 802.16 is an attractive broadband wireless
technology for these scenarios, non-withstanding its limitations for dynamic
environments.
This Thesis discusses a network architecture able to support IPv6 QoS aware
real time services using 802.16 networks. Specifically, this solution supports
dynamic and fast access from the Mobile Nodes to the network services, as
well as dynamic reservations and modifications of services. These fast and
dynamic reservations are crucial to the support of fast mobility approaches.
Moreover, the proposed solution is also able to provide IPv6 support and
efficient traffic differentiation for services running on the same MN.
This Thesis presents the envisioned architecture, the modules required to
provide the integrated QoS approach over the 802.16 network, the
implementation of the modules to build a real network, and address main
implementation results in terms of QoS performance, and in terms of mobility
with QoS support for converged networks comprising WiMAX and Wi-Fi
technologies. The obtained results show that our architecture is able to provide
end-to-end QoS over the concatenation of metro and local area networks, and
that seamless mobility is achieved with high performance measures, thus being
able to support real-time services