Much of wireless research today focuses on improving capacity of wireless

networks. While wireless capacity can be a critical issue in cases where the

number of users is large, or for high bandwidth applications such as video

downloads, we find that this is not the case in day-to-day environments such as

corporate WLANs, universities, homes, cafe's etc. Through empirical measurements

in each of these networks, we show that even at peak usage, wireless networks

have plenty of spare capacity. For the range of networks that we measured, we

found medium utilization remains under 50% for upto 90% of the time. The

traffic patterns are bursty, and utilization can reach as much as 80% in some

cases on very short timescales, but for most part, there is plenty of capacity

available. Ironically, we find that while capacity is plentiful, packet loss

remains a problem. Our measurements show that these wireless links on an average

suffer from loss rates of about 10%. We discuss the causes and implications of

these observations, and consider how our results might guide protocol design.

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