lol, I have no idea?? We allegedly have Comcast/Xfinity's fastest plan ... whatever that means. I'm not super impressed.
... just looked it up, Comcast advertises my download speed as "up to 50 mbps" ... however, when I took the test, I got a value of 4.20 mbps for download and 6.02 mbps for upload --- not quite as fast advertised