The fastest advertised download speed is listed at 2,000 Mbps for Xfinity, but at this point in time it is a little cost prohibitive. This speed is a little skewed though because even though it is listed as this speed it has a disadvantage in the form of asymmetric upload speeds. This means that internet service providers (ISPs) will give customers much slower upload speeds than the advertised download speeds. It is usually about 10%, so in this case Xfinity would have an upload bandwidth of 200 Mbps. There are a few providers around the United States that offer speeds up to 10,000 Mbps, but they are pretty rare and are almost certainly overkill. If we were looking for the fastest speed for upload and download then it would have to be Google fiber. It boasts 1,000 Mbps for downloads and uploads, something no one else can match. This is roughly 100 times faster than what most Americans have. Fiber is currently the fastest kind of internet with speeds up to 10,000 Mbps in some areas. It uses glass fiber-optic threads bundled together to transfer light signals, which are fast and reliable over long distances. With it being one of the newer ways to send signals it doesn't have the same speed issues that older types of internet connections have. There will always be different ideas coming out to make internet connections faster.