In this paper, we revisit the widely known performance anomaly that results in severe network utility degradation in WiFi networks when nodes use diverse modulation and coding schemes. The proportional-fair allocation was shown to mitigate this anomaly and provide a good throughput to the stations. It can be achieved through the selection of contention window values based on the explicit solution of an optimization problem or, as proposed recently, by following a learning-based approach that uses a centralized gradient descent algorithm. In this paper, we leverage our recent theoretical work on asynchronous distributed optimization and propose a simple algorithm that allows WiFi nodes to independently tune their contention window to achieve proportional fairness. We compare the throughputs and air-time allocation that this algorithm achieves to those of the standard WiFi binary exponential back-off and show the improvements.
翻译:在本文中,我们重新审视了在节点使用多种调制和编码办法时导致WiFi网络网络的网络功用严重退化的广为人知的功能异常现象。 比例公平分配表明可以缓解这种反常现象,为站点提供良好的输送量。 可以通过明确解决优化问题的办法选择争议窗口值,或者如最近提议的那样,采用基于学习的方法,采用集中的梯度下降算法。 在本文中,我们利用我们最近关于非同步分布式优化的理论工作,并提出了一个简单的算法,使WiFi节点能够独立调整其争议窗口,以实现比例公平。 我们比较了该算法实现的流量和空时分配与标准的 WiFi 二进制指数反转,并展示了改进。