We propose a new class of channel allocation algorithms that are simple, robust and require no communication between interfering WLANs. We show they are provably correct and yet remarkably efficient under a wide range of network conditions and topologies. The algorithms are suited to implementation on standard equipment, requiring no special hardware support and making only light demands on computational resources. We demonstrate this by implementing algorithms on an experimental testbed using commodity hardware. We present detailed measurements of performance in a real office environment. This environment includes complex spatially-varying noise, channel-dependent interference between WIANs, time-varying channel quality and external interference sources. Despite these challenges the algorithm performs well. (C) 2012 Elsevier B.V. All rights reserved.