Ring Elite (PoE): minimum download&upload speed? Max cable length?

Hi,Does anyone know what the minimum down-and upload speed is for a Ring Elite doorbell? The reason I'm asking is that someone is interested in this system, however his Internet signal is not coming from a cable but from a roof parabola. And the speed 'is what it is'. I'm not sure it'll be enough to be able to talk to and see the person ringing his doorbell. Also: the physical distance between his modem and the entry gate is around 30 meters: will that work?