Far from being ripe for replacement, copper is still bearing fruit as vendors squeeze ever more bandwidth from aging phone lines, and it's not likely to dry up anytime soon, according to Marcus Weldon, president of Bell Labs and CTO of Alcatel-Lucent.
Last July, Bell Labs , the research arm of Alcatel-Lucent (NYSE: ALU), claimed to have set a new world record for broadband speeds over copper of 10 Gbit/s, using a technology it calls XG-FAST. Industry observers could have been forgiven for thinking that was about as much capability as the equipment vendor would ever get from a test network not based on FTTH architecture.
But Weldon thinks Bell Labs can do even better. "I'm sure we'll find a way of doing 30 Gbit/s or 40 Gbit/s," he tells Light Reading. "We're getting to the point where copper is almost outpacing fiber in the access domain."
Multi-gigabit copper clearly has a long way to go before it sees the commercial light of day, but Weldon's confidence in copper will bring a smile to the faces of executives at BT Group plc (NYSE: BT; London: BTA) and Deutsche Telekom AG (NYSE: DT) -- major European operators that have continued to resist investing in FTTH networks, despite the mounting pressure they are feeling from cable operators preparing for a DOCSIS 3.1 future.
Using G.fast, a standardized predecessor of XG-FAST, BT reckons it will be able to provide speeds of up to 500 Mbit/s to most UK premises over the next few years, and even support 1Gbit/s services for the most bandwidth-hungry customers. (See G.fast: The Dawn of Gigabit Copper? and BT Puts G.fast at Heart of Ultra-Fast Broadband Plans.)
So far, Deutsche Telekom has been revving up its broadband network through the use of vectoring, which can increase bandwidth to a theoretical high of 100 Mbit/s by cutting out interference between lines. (See Vectoring: Some Va-Va-Voom for VDSL and DT Expands Its Vectoring Commitments.)
But it also has G.fast in its sights. At Mobile World Congress held in Barcelona earlier this month, the German incumbent promised that over the next few years it would increase broadband speeds to 500 Mbit/s for about 12% of households across its European footprint. Although it is planning FTTH rollouts in some countries, it expects copper-fortifying technologies like G.fast to fit the bill elsewhere. (See DT's Höttges Says Hybrid Is 'Not Answer to Cable'.)
Even so, as Weldon acknowledges, getting from G.fast to XG-FAST will not be a straightforward upgrade. Chips will need changing, for one thing, and fiber will need to be extended even closer to the customer premise.
"It'll have to be about 30 to 50 meters away from the end user, instead of 100 meters with G.fast," says Weldon. "But you'll be saving on that drop to the house, which is the most expensive part of the deployment."
Weldon is skeptical that homes will need services of 10 Gbit/s or more but reckons XG-FAST and subsequent technologies could be ideal for small offices with multiple tenants.
Before any of that happens, of course, the industry can look forward to some G.fast improvements. Current deployments use up to 106MHz of spectrum, compared with just 17MHz in vectored VDSL2 networks, but a new version of G.fast that is "just about finalizing" -- according to Weldon -- will increase the available spectrum to as much as 212MHz.
Fiber remains the ultimate goal for just about every player, but operators may be able to keep milking those copper assets for some time yet.
— Iain Morris, , News Editor, Light Reading