Because I live in a bus, I use paid-for hotspots to connect to the internet. Sometimes I'm quite far from a hotspot, so I was thinking to use a raspberry-pi with both an ethernet connection and a wifi, attached to a long ethernet cable as my router. Now my questions are about the powersupply and possible interference with the ethernet cable. So, can I use a Cat5e and use the blue or brown wires to provide power over the same cable ? (Which I would then have to separate from the rest before they go in the RJ-45 connector, because I don't suppose the raspberry would support PoE)
Or would it better to be using a seperate ethernet cable for the power supply ?
How much Power would I need to provide at the source in order to still have 5 Volts over i.e. a 30 m ethernet cable ?