Well, the record was recently broken by a Japanese internet provider, So-net, branch of electronics giant Sony, which offers a new fiber optic internet service called "Nuro" for residents of Tokyo, Japan.
Speed? 2 Gbps or twice Google Fiber. So-net parties claiming the internet connection is the fastest in the world.
Nuro using Gigabit network-capable Passive Optical Network (GPON) Japan could reportedly reach speeds of 2.488 Gbps downstream.