Bell Labs, the research arm of networking company Alcatel-Lucent, has achieved broadband speeds of 10 gigabits per second over copper phone lines, setting a new record. The test demonstrates how existing copper networks can be used to deliver 1Gbps symmetrical broadband, according to Alcatel-Lucent.
It’s a feather in the cap for proponents of fibre-to-the-node, which relies on copper for the 'last mile' connection to premises. In Australia, the Coalition government has pushed FTTN as the main technology for delivering the National Broadband Network.
NBN Co has previously purchased VDSL2 vectoring technology from Alcatel-Lucent. The government-owned company is currently conducting large-scale FTTN testing in conjunction with Telstra.
In the recent round of tests Bell Labs achieved 1Gbps symmetrical speeds over 70 metres on a single copper pair. The testers also achieved 10Gbps over a distance of 30 metres by using two pairs of lines, a technique called bonding. Both tests used standard copper cable provided by a European operator.
Bell Labs cautioned that results might be different in real-world conditions.
“In practical situations, other significant factors that can influence actual speeds (not taken into account during these tests but which have been studied extensively elsewhere) include the quality and thickness of the copper cable and cross-talk between adjacent cables (which can be removed by vectoring),” an Alcatel-Lucent statement said.
“Achieving 1Gbps 'symmetrical' services – where bandwidth can be split to provide simultaneous upload and download speeds of 1Gbps – is a major breakthrough for copper broadband.
“It will enable operators to provide Internet connection speeds that are indistinguishable from fiber-to-the-home services, a major business benefit in locations where it is not physically, economically or aesthetically viable to lay new fiber cables all the way into residences. Instead, fiber can be brought to the curbside, wall or basement of a building and the existing copper network used for the final few meters.”
Bell Labs used a prototype technology called XG-FAST. It is an extension of G.fast technology, a new broadband standard currently being finalised by the International Telecommunication Union (ITU) that is expected to be available in 2015.