# Providing Throughput and Fairness Guarantees in Virtualized WLANs Through Control Theory

## Abstract

With the increasing demand for mobile Internet access, WLAN virtualization is becoming a promising solution for sharing wireless infrastructure among multiple service providers. Unfortunately, few mechanisms have been devised to tackle this problem and the existing approaches fail in optimizing the limited bandwidth and providing virtual networks with fairness guarantees. In this paper, we propose a novel algorithm based on control theory to configure the virtual WLANs with the goal of ensuring fairness in the resource distribution, while maximizing the total throughput. Our algorithm works by adapting the contention window configuration of each virtual WLAN to the channel activity in order to ensure optimal operation. We conduct a control-theoretic analysis of our system to appropriately design the parameters of the controller and prove system stability, and undertake an extensive simulation study to show that our proposal optimizes performance under different types of traffic. The results show that the mechanism provides a fair resource distribution independent of the number of stations and their level of activity, and is able to react promptly to changes in the network conditions while ensuring stable operation.

## Keywords

wireless LAN virtualization 802.11 control theory throughput optimization fairness## Notes

### Acknowledgements

This work has been partly supported by the European Community’s Seventh Framework Programme (FP7-ICT-2009-5) under grant agreement n. 257263 (FLAVIA project), and by the Spanish Government, MICINN, under research grant TIN2010-20136-C03.

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