High-speed versions of DSL that can reach 1 Gbps on very short copper local loops and speeds up to 150 Mbps on loops not longer than 250 meters. In contrast, one-kilometer VDSL2 loops support speeds of approximately 50 Mbps. G.fast uses time-division duplexing, whereas VDSL2 and ADSL2 use frequency-division duplexing. Formally the ITU G.9700 and G.9701 standards, deployment began in 2016. See local loop.