A roommate of mine asked me to connect a powerline adapter to the network. The ethernet cable of the adapter is connected to an Apple Airport Express router which is connected to a Frontier Internet cable modem. I have another router from Frontier connected to the Frontier Internet cable modem.
Adapter > Airport > ISP Cable Modem > ISP router
However all of the electric plugs for everything are plugged into a multi-outlet surge protector which in turn is plugged into the powerline adapter, and the powerline adapter is plugged into the home's wall outlet.
So since my rudimentary understanding of a powerline adapter is that they use the electricity to transmit data, my question is does the person with the receiving end of the powerline adapter connection have an "easier" time sniffing traffic of a person connected to the Frontier router? (let's assume the person is practicing good wifi security and has a strong password, etc.). Mostly I'm worried by plugging the Frontier router power plug into the surge protector which in turn is plugged into the powerline adapter, I'm not really keeping the traffic "separated" and the roommate on the receiving end of the powerline adapter now will be able to "easily read" the traffic data going into/from the Frontier router.