Idea of Powerline Icon
This icon "Lan Over Powerline" looks similar to an electrical socket. It's a large rectangle with a height greater than its width. Inside of the rectangle, at the top, is a circle, inside of which are two small holes next to one another. At the bottom of the rectangle is small rectangular shape with three black lines at its top.
This is a Powerline icon. It is available in PNG and vector. Downloading is free for PNGs up to 100x100px.