Those cheap eBay items you reference are likely just sending power over an unused pair. Actual standardized PoE has all sorts of other cool perks. I haven't stu

Those cheap eBay items you reference are likely just sending power over an unused pair. Actual standardized PoE has all sorts of other cool perks. I haven't studied it heavily but I wouldn't say they're quite the same as the little dongles with a plug off the side.