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The transport protocols for Wireless Body Area Networks (WBANs) must provide end-to-end reliability and Quality of Service (QoS) for the whole network. This task can be accomplished through the reduction of the PLR (Packet Loss Ratio) and the latency while keeping fairness and low energy consumption between the nodes. The IEEE 802.15.6 Standard supports QoS, but it does not suggest any transport protocol...
Next generation network(NGN) is an All-IP based heterogeneous network which includes wired network, satellite network, wireless mobile network and so on. Comparing with the traditional wired network, in NGN, the classical TCP/IP is beginning to show signs of age. In order to cope with problems such as the poor performance of wireless links and mobile terminals, including the high error rate of wireless...
We present a performance study of a wireless mesh network based on off-the-shelf 802.11 technology. Unlike earlier work, we explore the practical constraints of the use of a “vanilla”, unmodified 802.11 MAC layer. We also consider the use of multiple radios, in the 5GHz band, to reduce interference. We establish the origin of degradation and limits in performance of practical deployments and study...
With the development of the wireless communications technology and the multimedia technology, the wireless internet multimedia transport of real-time becomes an important applications field. We will meet a problem that the distinguish of the status of package loss is not very good which will affect the QoS when we transport multimedia data in wireless internet. Based on this problem the article comes...
This paper presents a methodology for evaluating the quality of service (QoS) provided by a Universal Mobile Telecommunications System (UMTS) network for data services that use HTTP. Data collected from drive testing were used as the means to evaluate different drive routes of varying quality. The methodology presented in this paper can be easily modified to work with different networks.
The problem how to improve the quality of server(QoS) of the heterogeneous network must be studied and solved, for long round trip times (RTTs), not negligible packet error rates (PER), and downlink-uplink asymmetry, etc. Posing new challenges to the QoS given by transmission control protocol (TCP). the paper proposes a Diff-selective(diff-sel) policy, which can solve the problem by selecting different...
In order to effectively monitor the application of the network performance and service quality, rapidly response users' needs and complaints, telecom operators find that the demands for service quality are in an urgent case. According to the requirement analysis on quality monitoring for streaming media service, together with the characteristics of stream media transport protocol, this paper introduced...
The IEEE 802.16 standard (mobile broadband wireless access system), which is also known as worldwide interoperability for microwave access (WiMAX), is one of the latest technologies in the wireless world. The main goal of WiMAX is to deliver wireless communications with quality of service (QoS) guarantees, security, and mobility. In this article, we have evaluated the performance of the Internet Protocol...
Access networks based on cooper cables are costly to build and maintain. For this reason, last-mile access networks based on wireless technologies are gaining considerable attention. Among the wireless technologies being employed, the IEEE802.11 is common place. In such scenarios it is important to have well defined mechanisms to better evaluate traffic characteristics and overall system performance...
There has been considerable research into the performance of the enhanced IEEE 802.11e standard in recent years. Majority of the performance analysis has been based on simulations and analytical models, with little testing done in a real-world environment. We investigate the behaviors of the enhanced distributed channel access (EDCA) and legacy distributed coordination function (DCF) based on a testbed...
We propose QoS-aware mesh deterministic access opportunities (MDAOPs) assignment algorithm for the IEEE 802.11s wireless mesh networks (WMNs). The WMNs can benefit from the mesh deterministic access (MDA) in terms of guaranteeing the QoS of the delay bounded traffic, mitigating the exposed node problem, and providing the fairness among best effort traffic flows. However, it is not considered that...
In this paper, we present a new analysis of the optimal throughput of a single user for transporting MPEG-4 video over universal mobile telecommunication system (UMTS) network. A wireless channel considers that bit errors associated with link-layer packets are due to the time-varying features of a wideband code-division-multiple access (WCDMA) channel. By this network, the perceived video quality...
Wireless networks and multimedia applications are two rapidly emerging technological trends. The IEEE 802.11e protocol has been developed to support QoS for such delay-sensitive applications in wireless networks. This protocol has also been extensively studied in the literature over the past few years, and several mechanisms to improve its performance have been proposed concentrating on ways to reinforce...
Using the application of bluck data transfer, we investigate the performance of QoS-satisfied pathover for transport layer mobility scheme such as mSCTP in FMIPv6 envirmonment. We find that existing scheme has some defects in aspect of pathover and throughput. Based on this, we make a potential change to mSCTP by adding QoS-Measurement-Chunk, which is used to take into account information about wireless...
This paper discusses the inter-layer mobility and quality of service (QoS) support in a multi-tier Wireless Overlay Network (WON). It proposes integrated network architecture with layer manager for vertical handoff, switching and mobility management using Mobile IP protocol. Various functionalities of the Layer manager are implemented as modular blocks and are distributive over the gateways in each...
The IEEE 802.16 standard, also known as WiMAX, has yet to prove its effectiveness when the end terminals are not static and free to move at vehicular speeds. High bit error rate caused by multipath fading at high vehicular speeds, is the key reason for low throughput at high speeds. Standard error control mechanisms like transmission control protocol (TCP) and forward error correction (FEC) have limited...
The future airborne network (AN) has to operate with lossy and intermittent data links, and other harsh technical challenges. However, current network protocols cannot perform well in AN, because they were originally developed for terrestrial-based Internet. Although some protocols were modified to adapt to space links, there is little research so far on reliable transmission mechanisms in AN environment...
Goal of the reported experiment was to determine in which way wirelessly transmitted video streams influence each other. Former experiments gave the impression that the behavior of video streams is unpredictable, e.g. due to unstable play-back and uncertain starts. To transport two video streams simultaneously over a wireless/wired network, the video servers use different network protocols (TCP and...
With the advent of multimedia applications over wireless local area networks (WLANs), the IEEE 802.11e standard was proposed to incorporate quality of service (QoS) parameters in the medium access control (MAC) layer. It has been found through previous research work that the throughput of transport control protocol (TCP) is less when compared to that of User Datagram Protocol (UDP) in the IEEE 802...
Widespread deployment of Wi-Fi together with 3G upgrades to cellular networks is rapidly creating areas where multiple wireless IP technologies will coexist. WiMAX will further contribute to this phenomenon. The ability to use diverse access technologies simultaneously creates opportunities to improve application service quality and reliability. In this paper, we present an intelligent connectivity...
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