23 research outputs found

    Low-cost QoS-enabled Wireless Network with Interworked WLAN and WiMAX

    Full text link
    The WLAN and WiMAX standards are candidate solutions for a low-cost broadband wireless network. Interworking the two networks, using the network-layer QoS mechanisms of the Next Generation Network, will allow them to complement each other. This paper proposes integrating the WLAN and WiMAX link-layer QoS mechanisms of the NGN to ensure that QoS is maintained over the wireless link. The wireless QoS mechanism in WLAN and WiMAX are analyzed and an integration framework is propose

    A quality of service architecture for WLAN-wired networks to enhance multimedia support

    Get PDF
    Includes abstract.Includes bibliographical references (leaves 77-84).The use of WLAN for the provision of IP multimedia services faces a number of challenges which include quality of service (QoS). Because WLAN users access multimedia services usually over a wired backbone, attention must be paid to QoS over the integrated WLAN-wired network. This research focuses on the provision of QoS to WLAN users accessing multimedia services over a wired backbone. In this thesis, the IEEE 802.11-2007 enhanced data channel access (EDCA) mechanism is used to provide prioritized QoS on the WLAN media access control (MAC) layer, while weighted round robin (WRR) queue scheduling is used to provide prioritized QoS at the IP layer. The inter-working of the EDCA scheme in the WLAN and the WRR scheduling scheme in the wired network provides end-to-end QoS on a WLAN-wired IP network. A mapping module is introduced to enable the inter-working of the EDCA and WRR mechanisms

    Final report on the evaluation of RRM/CRRM algorithms

    Get PDF
    Deliverable public del projecte EVERESTThis deliverable provides a definition and a complete evaluation of the RRM/CRRM algorithms selected in D11 and D15, and evolved and refined on an iterative process. The evaluation will be carried out by means of simulations using the simulators provided at D07, and D14.Preprin

    Design and analysis of LTE-WLAN wireless router with QOS preservation

    Get PDF
    Future wireless networks are envisioned to embrace a higher level of heterogeneity whereby different wireless technologies such as Long Term Evolution UMTS (LTE), Wireless Local Area Network (WLAN), WCDMA/HSPA, WiMAX, etc, not only will coexist but will also cooperate more closely. This is motivated by the fact that several complementary characteristics exist between these technologies. For example, one technology can be used as access technology while the other can be used for backhaul. To interconnect two or more wireless technologies, the usage of routing device is inevitable. In order to preserve the Quality of Service (QoS) across these technologies which come with different QoS definitions, a more comprehensive approach is required to preserve QoS across two diverse wireless technologies i.e. Enhanced Distributed Coordination Function (EDCA) for WLAN and Uplink/Downlink packet scheduling for LTE. WLAN is reasonably priced, easy to deploy and has been enjoying a wide market acceptance especially in the indoor. The LTE is expected to be the dominant 4G cellular technology. However it will take some time before LTE can attain the same level of adoption as what WLAN has achieved especially in the consumer market. The main objective of this research project is to design an access router that enables the interworking between WLAN and LTE with QoS preservation. First, the performance of both WLAN and LTE radio interfaces are investigated independently in terms of the data rates, user/system throughput, effect of multiple access and spectral efficiency. Next, different approaches and schemes which facilitate QoS preservation between WLAN and LTE over the router are investigated and evaluated in terms of different performance metrics (voice Mean Opinion Score, video delay, video traffic received, video jitter, video packet loss rate). The design and analysis of the performance are carried out through simulation as the only feasible approach to accomplish this work. OPNET Modeler is used to model the LTE-WLAN router as well as to perform the analysis. The results of this research verify the feasibility of the proposed router architecture and the interworking paradigm. The elegance of the proposed router implementation is that it does not require massive change in the existing wireless systems, LTE and WLAN to preserve the QoS. The results of the performance analysis show that it is crucial to have a QoS preservation mechanism in the router IP layer at any potential congestion point in the wireless network, to ensure that delay-sensitive and loss-sensitive applications, such as real-time video and voice, pass through unimpeded, relative to the loss-tolerant and delay-tolerant data applications. The comparison of the designed IP QoS preservation scheme namely, Priority Queuing without Block Acknowledgement (PQ noBA) shows that it can support 50% more multimedia application across the router than the other scheme

    EVEREST IST - 2002 - 00185 : D23 : final report

    Get PDF
    Deliverable públic del projecte europeu EVERESTThis deliverable constitutes the final report of the project IST-2002-001858 EVEREST. After its successful completion, the project presents this document that firstly summarizes the context, goal and the approach objective of the project. Then it presents a concise summary of the major goals and results, as well as highlights the most valuable lessons derived form the project work. A list of deliverables and publications is included in the annex.Postprint (published version

    Experimental analysis of WiMAX and meshed Wi-Fi quality of service

    Get PDF
    Mestrado em Engenharia Electrónica e TelecomunicaçõesA indústria das telecomunicações tem sofrido uma evolução enorme nosúltimos anos. Tanto em termos de comunicações sem fios, como em termos deligações de banda larga, assistiu-se a uma adesão massiva por parte domercado, o que se traduziu num crescimento enorme, já que a tecnologia temque estar um passo à frente da procura, de forma a suprir as carências dosconsumidores. Assim, a evolução persegue um objectivo claro: possibilidadede possuir conectividade de banda larga em qualquer lugar e instante. Nestecontexto, aparecem as tecnologias WiMAX (Worldwide Interoperability forMicrowave Access) e WI-FI em Malha como possibilidades para atingir estefim. O tema desta dissertação incide no estudo das tecnologias de WiMAX e WI-FIem Malha, mais concretamente no estudo da Qualidade de Serviço (QoS)providenciada pelas normas IEEE 802.16 e IEEE 802.11s para serviços deVoIP e VoD. Esta tese apresenta a arquitectura desenvolvida para a correcta integração deQoS para serviços em tempo real no acesso à banda larga sem fios depróxima geração. De seguida, apresenta testes efectuados com osequipamentos disponíveis de WiMAX e WI-FI em Malha, de forma a mostrar ocorrecto comportamento da atribuição extremo-a-extremo de QoS nos cenáriosescolhidos com serviços em tempo real, bem como os efeitos da mobilidade natecnologia WI-FI em Malha. ABSTRACT: The telecommunication industry has suffered a massive evolution throughoutpast years. In terms of wireless communications, as well as broadbandconnections, we’ve seen a massive adoption by the market, which conductedinto an enormous growth, since the technology must always be one step aheadof the demand, in order to be to fulfill the needs of the consumers. Therefore,the evolution pursues one clear goal: the possibility to establish a broadbandconnection anywhere and anytime. In this context, the WiMAX (WorldwideInteroperability for Microwave Access) and Meshed WI-FI technologies appearas possibilities to reach this goal. The subject of this thesis is the study of both the WiMAX and Meshed WI-FItechnologies, and more concretely the study of the QoS provided by theIEEE802.16 and IEEE 802.11s standards to VoIP and VoD services. This thesis presents the architecture developed to provide the correctintegration of QoS for real-media traffic in next generation broadband wirelessaccess. It presents tests carried out with the available WiMAX and Meshed WI-FI equipments, to show the correct behavior in the attribution of end-to-endQoS in selected scenarios with real-time services, as well as mobility effects onWI-FI Wireless Mesh technology

    Quality of service based distributed control of wireless networks

    Get PDF

    Quality of service differentiation for multimedia delivery in wireless LANs

    Get PDF
    Delivering multimedia content to heterogeneous devices over a variable networking environment while maintaining high quality levels involves many technical challenges. The research reported in this thesis presents a solution for Quality of Service (QoS)-based service differentiation when delivering multimedia content over the wireless LANs. This thesis has three major contributions outlined below: 1. A Model-based Bandwidth Estimation algorithm (MBE), which estimates the available bandwidth based on novel TCP and UDP throughput models over IEEE 802.11 WLANs. MBE has been modelled, implemented, and tested through simulations and real life testing. In comparison with other bandwidth estimation techniques, MBE shows better performance in terms of error rate, overhead, and loss. 2. An intelligent Prioritized Adaptive Scheme (iPAS), which provides QoS service differentiation for multimedia delivery in wireless networks. iPAS assigns dynamic priorities to various streams and determines their bandwidth share by employing a probabilistic approach-which makes use of stereotypes. The total bandwidth to be allocated is estimated using MBE. The priority level of individual stream is variable and dependent on stream-related characteristics and delivery QoS parameters. iPAS can be deployed seamlessly over the original IEEE 802.11 protocols and can be included in the IEEE 802.21 framework in order to optimize the control signal communication. iPAS has been modelled, implemented, and evaluated via simulations. The results demonstrate that iPAS achieves better performance than the equal channel access mechanism over IEEE 802.11 DCF and a service differentiation scheme on top of IEEE 802.11e EDCA, in terms of fairness, throughput, delay, loss, and estimated PSNR. Additionally, both objective and subjective video quality assessment have been performed using a prototype system. 3. A QoS-based Downlink/Uplink Fairness Scheme, which uses the stereotypes-based structure to balance the QoS parameters (i.e. throughput, delay, and loss) between downlink and uplink VoIP traffic. The proposed scheme has been modelled and tested through simulations. The results show that, in comparison with other downlink/uplink fairness-oriented solutions, the proposed scheme performs better in terms of VoIP capacity and fairness level between downlink and uplink traffic
    corecore