A statistical hypothesis is an assumption about a population parameter. This assumption may or may not be true. Hypothesis testing refers to the formal procedures used by statisticians to accept or reject statistical hypotheses. The best way to determine whether a statistical hypothesis is true would be to examine the entire population.
Dynamic Frequency Selection. DFS is a spectrum-sharing mechanism that allows wireless LANs (WLANs) to coexist with radar systems. It automatically selects a frequency that does not interfere with certain radar systems while operating in the 5 GHz band.DFS is a feature of ETSI BRAN HIPERLAN/2 and IEEE Standard 802.11h.FS detects radar interference and moves the wireless network to another frequency with no interference. It maintains a list of channels where radar has been detected in the NOL (non-occupancy list). The AP avoids using these channels for at least 30 minutes after detecting radar on them.
The wireless device automatically sets the frequency on a DFS-enabled 5.0 GHz (802.11a/h) radio operating in a regulatory domain where DFS is required for compliance with the rules of that regulatory agency. If the wireless device selects a DFS-required channel, it scans the new channel for radar signals for 60 seconds. If there are no radar signals on the new channel, the wireless device enables beacons and accepts client associations. If a radar signal is detected, the wireless device selects a different channel.