CWNA Wireless Network Administrator

Answer - D - The statement that is true about PoE devices from different manufacturers is that they may cause damage to devices from other vendors.

Key Takeaway: Power over Ethernet, or PoE technology, describes a system to safely pass electrical power, along with data, on Ethernet cabling. Because no standard yet exists for PoE, manufacturers implement PoE in various ways. Various voltages and polarities are used, as well as different sets of unused pins in the Cat5 cable. Hence, you should always try to use both wireless LAN and PoE equipment from the same vendor. This ensures they are compatible and no electrical damage will be caused.