Hello Sarah,

PoE is supported also on 1000 baseT the key is that the power is a DC signal while the ethernet signal is variable over time ( = use higher frequencies so they can be splitted)

However, a GE capable IP phone is more hungry of power this has led to rapid consumption of power supplies in our more modern campus

if it takes 12W instead of 7W for example it makes quite a difference

Hope to help

Giuseppe