I've been studying for the CWNA exam and was reading over the part about properly grounding the WLAN equipment outside using lightning arrestors. I feel this is a good practice to follow, but realized in many cases the equipment I've installed is totally integrated. Meaning the antenna and AP are builtin together and then both powered by a PoE injector (like SmartBridges AirPoint Pro Total).
So my question is it necessary to ground equipment like this, or is it already being grounded through the buildings power outlet that the PoE injector plugs into? If further measures are needed what are they?