# Decentralised learning MACs for collision-free access in WLANs

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## Abstract

By combining the features of CSMA and TDMA, fully decentralised WLAN MAC schemes have recently been proposed that converge to collision-free schedules. In this paper we describe a MAC with optimal long-run throughput that is almost decentralised. We then design two schemes that are practically realisable, decentralised approximations of this optimal scheme and operate with different amounts of sensing information. We achieve this by (1) introducing learning algorithms that can substantially speed up convergence to collision free operation; (2) developing a decentralised schedule length adaptation scheme that provides long-run fair (uniform) access to the medium while maintaining collision-free access for arbitrary numbers of stations.

## Keywords

Learning MAC Collision-free MACs Convergence time Schedule length adaptation## Notes

### Acknowledgments

Work supported by SFI Grant 07/SK/I1216a, the European Community’s 7th Framework Programme (FP7-ICT-2009-5) under grant agreement n. 257263 (FLAVIA project) and HEA's Network Maths Grant.

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