Tahiry RAZAFINDRALAMBO Education
نویسنده
چکیده
description Design, analysis and implementation of wireless protocols and algorithms. One of the main challenge in wireless ad hoc networks is Medium Access Control. The IEEE 802.11 standard provides a communication mode called DCF (Distributed Coordination Function) that is fully distributed and suitable for ad hoc networks. However, the MAC (Medium Access Control) protocol described in 802.11 shows some fairness and efficiency issues. The fairness guarantees that any wireless station will access correctly the medium, and the efficiency guarantees the full usage of the wireless medium. Many existing solutions, designed to improve IEEE 802.11, provide either efficiency or fairness. My research interest has been focused on two different axes. The first axis is the performance evaluation of existing wireless protocols especially 802.11. I have highlighted the performance issues of 802.11 by studying its CSMA mechanisms coupled with different backoff algorithms thanks to a generic model based on stochactic process algebra. The second axis of my research is the design of new fair and efficient MAC protocols for wireless LANs and wireless ad hoc networks. The results derived from my first research axis were used to develop such MAC protocols. Our protocols are different from those presented in the literature because they initially address the trade-off between efficiency and fairness. Thus, our proposed solutions are both efficient and fair.
منابع مشابه
Mouvements Autonomes : vers la Créativité dans les Réseaux sans fil. (Autonomous Movements : toward Creativity in Wireless Networks)
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HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau...
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