BT (NYSE: BT) revealed that during its trial of G.FAST, a technology that allows service providers to gain higher speeds over existing copper on short loop lengths using a fiber-to-the-distribution point (FTTdp) architecture, it achieved combined downstream and upstream speeds of up to 1 Gbps.
Over a 19 meter length of existing copper, BT said it achieved downstream speeds of about 800 Mbps and upstream speeds of over 200 Mbps in the trial. On longer lines of 66 meters, a distance that it says encompasses about 80 percent of such connections, the telco reported speeds of around 700/200 Mbps.
FTTdp was a key player in the trials. It can achieve the higher speed rates by bringing fiber closer to the customer premises than a fiber-to-the-cabinet (FTTC) configuration and using higher frequencies, plus advanced crosstalk cancelation techniques.
The technology has a number of potential advantages for BT and its customers. For the service provider it means less fiber and civil engineering, while reducing truck rolls to each premise because customers could potentially install the equipment in their homes themselves.
These trials were supported by BT Openreach's last mile fiber network, one that currently passes over 20 million UK premises using a mix of fiber-to-the-premises (FTTP) and FTTC network technologies.
While BT has been rolling out FTTP in select areas, it carries a much higher cost than FTTC. Over its FTTC network, the service provider can deliver up to 80 Mbps of bandwidth to eligible users. In a FTTC configuration, BT brings a fiber cable to a local remote terminal (RT) cabinet and uses VDSL2 to carry the broadband signal over the existing copper connection to the premises. Although VDSL2 can work up to 2,000 meters, most of the homes BT serves are under 400 meters.
In tandem with the completion of its G.FAST trial, BT has created a new lab in Adastral Park where it will research the capabilities of a number of key system vendors, such as Adtran, Alcatel Lucent (NYSE: ALU) and Huawei.
"We see G.FAST as a very promising technology with significant potential--that's why we're putting some of our best minds on the case to assess it fully in a purpose-built facility," said Tim Whitley, managing director of Research and Innovation for BT Group, in a release.
BT appears to be realistic about the prospects of G.FAST, noting that network equipment is still "immature," but approval of the ITU G.9701 recommendation is expected in December and the first viable hardware should begin to come out around the same time.
Despite G.FAST's advertised potential, ISPReview notes tha
G.FAST is just one of various technologies BT is trialing to get more juice out of its existing copper lines. In August, the service provider conducted the second phase of its VDSL vectoring trial, which it claims could enhance the speeds of its "up to" 80 Mbps-capable FTTC network.
- see the release
- ISPreview has this article
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