Dynamic Frequency Selection (DFS) makes use of 5 GHz channels typically reserved for radar and government in the US, but are available for general use.
Dynamic Frequency Selection (DFS) refers to the use of 16 of the available 25 channels on the 5 GHz band that are generally reserved for weather radar, military radar, and satellite communications. These specific channels are referred to as “DFS Channels”.
Note: this is applicable to the United States; DFS channels vary from country to country.
With 16 additional channels, this means greater capacity for 5 GHz wifi networks and faster performance.
Due to regulations, when an AP is operating on a DFS channel, it must continuously scan for the presence of radar activity, cease transmitting if such activity is detected, and switch to another channel.
Considering the performance potential, it is encouraged that DFS channels are used. If you do so, keep an eye on event logs generated by your AP which will record if radar activity is detected, forcing it to change channels. If you notice that a particular DFS channel is causing issues, remove it from your channel plan.