WiFi devices can use very little power and have better system performance that other low power battery operated radio systems. The WiFi Access Point knows about sleeping devices, and stores any packets aimed in their direction. The Access Point includes information about stored packets in the beacons that it transmits 10 times each second. The sleeping device can discover pending data by waking up for short periods (say just before every 50th beacon). This requires very little energy. Through this mechanism, a low power WiFi device can have battery life comparable to other low power radios, and at the same time be responsive to system demands, and even operate as a server.