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arXiv · 1501.01422

CSMA/CA Bottleneck Remediation in Saturation Mode with New Backoff Strategy

Baher Mawlawi·Jean-Baptiste Doré
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Abstract

Many modern wireless networks integrate carrier sense mul-tiple access/collision avoidance (CSMA/CA) with exponential backoff as medium access control (MAC) technique. In order to decrease the MAC overhead and the collision probability, we propose in this paper a new backoff strategy leading to better saturation throughput and access de-lay performance comparing to the classical protocol. We investigate the CSMA/CA with RTS/CTS technique, and we show that our strategy reaches better saturation throughput and access delay especially in dense networks. This proposed strategy distributes users over all the backoff stages to solve the bottleneck problem present in the first backoff stage. Finally, we analyze our strategy and we compare it to the classical one modeled by Markov chain. Analytical and simulation results show the improvment in term of saturation throughput. Cumulative density func-tion (CDF) of the access delay illustrates the important gain obtained by the proposed strategy.

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Baher Mawlawi, Jean-Baptiste Doré. 2015-01-07. CSMA/CA Bottleneck Remediation in Saturation Mode with New Backoff Strategy. https://doi.org/10.1007/978-3-319-03871-1_7

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