Abdelhamid Nafaa

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With the widespread IEEE 802.11 networks use, strong needs to enhance Quality of Service (QoS) has appeared. The IEEE 802.11 Medium Access Control (MAC) protocol provides a contention-based distributed channel access mechanism that allow for wireless medium sharing. This protocol involves a significant collision rate as the network gets fairly loaded.(More)
The advance of wireless networks is turning huge research interest into tremendous commercial success. Wireless local area networks (WLANs) are the most prominent example. With the ever increasing capacity of such networks, many interactive services (collaborative IP tools, VoIP, video streaming, push services, etc.) are emerging. Thanks to the rise of(More)
A number of works have tried to adjust the contention window in order to provide differentiated quality of service in IEEE 802.11-based wireless networks. By giving different service classes different CWs, the distribution of backoff intervals (chosen randomly, on the interval [O, CW]) will reflect the desired service classes. However, these protocols(More)
Many works have recently addressed the IEEE 802.11 QoS issues by proposing different monitoring-based contention window (CW) differentiation techniques. In network saturation, however, it is difficult to guarantee firm services differentiation while achieving high network exploitation. Particularly, most existing QoS-capable MAC protocols rely on a backoff(More)
Robust video streaming over Wireless Local Area Networks (IEEE 802.11) faces many challenges, including bandwidth channel variations, data errors/losses, and terminal capacity heterogeneity. This is worsen by the TCP/IP architecture that does not offer any quality of service (QoS) guarantees to demanding applications such as video streaming. In order to(More)
Most of QoS-capable IEEE 802.11 MAC protocols are unable to deliver sustained quality of service while maintaining high network utilization, particularly under congested network conditions. The problem often resides in the fact that flows belonging to the same service class are assigned the same MAC parameters regardless theirs respective bitrate, which(More)
Recently, many Active Queue Management (AQM) algorithms have been proposed to address performance degradations of end-to-end congestion control. However, these AQM algorithms present weaknesses for stabilizing delays in heavy loaded networks. In this paper, we describe a novel adaptive fuzzy control algorithm to improve best effort TCP/IP Networks(More)