PORTLAND, Ore. -- Bell Labs is back, recently setting a new world record of 10 gigabit per second over existing copper wires. Why is this important? Because it solves the fiber-to-residence problem.
Fiber cables for high-speed Internet services are being laid all throughout the country and world, but at a relatively slow rate due to the "curb-to-residence" problem. Many home owners are reluctant to let their lawns be dug up to lay fiber from the curb to the house, and many Internet providers are reluctant to incur the cost. Now Alcatel-Lucent's Bell Labs (Murray Hill, New Jersey) has a invented a solution -- a method of running 1-to-10 gigabit per second broadband signals from the curb to the residence using the existing copper telephone lines already there.
"Cost and time-to-market are the two of the biggest factors in bringing fiber to the home," Keith Russell, senior marketing manager for Alcatel-Lucent's Fixed Networks, told EE Times. "If you can imagine being a operator that is deploying and all fiber network they have to put new infrastructure into every unit. And as you put fiber into neighborhoods there's a high cost to that, but when you get to the curb and try to get across their property -- maybe digging up the lawn or going under the driveway -- there is a lot of cost to that too. Even avoiding that last little bit by using copper deployment can save an operator a lot of time and money."
The Bell Labs inventors of XG-Fast discuss how they were inspired by Bell Labs' most famous member, Claude Shannon.
Bell Labs' broadband-over-copper technology, called XG-Fast, is an extension of the digital subscriber line (DSL) standard under development at the International Telegraph Union Telecommunication (ITU-T) standardization group. Called G.fast, it is expected to deliver speeds of 200-to-500 megabits per second. By the time G.fast is deployed circa 2015, Alcatel-Lucent hopes to have readied commercial versions of Bell Labs G.fast extension -- XG-Fast -- offering 1-to-10 gigabit per second speeds. Bell Labs also demonstrated the "holy grail" of broadband-over-copper--1-gigabit per second symmetrical ultra-broadband access (allowing simultaneous uploads and downloads at 1-gigabit per second).
The limitations of XG-Fast, however, are that the 10-gigabit speed only for runs of 30 meters (98 feet) and requires bonding two copper pairs, whereas the 1-gigabit per second speed requires only a single copper pair, but can provide symmetrical ultra-broadband access for over 70 meters (230 feet), making it indistinguishable from Fiber-to-the-Home (FTTH).
Bell Labs' new XG-Fast carries broadband frequencies over copper from the curb to the residence at 1-to-10 gigabit per second broadband speeds.
XG-Fast offers its higher performance (over shorter distances) by upping the standard 106-megahertz frequency of G.fast, which gives it 500-megabits per second for 100 meters (328 feet), to 500-megahertz, thus achieving 10-gigabits per second speeds over a 30 meters. The 1-gigabit per second symmetrical speeds over 70 meters were achieved at a frequency of 350-megahertz.
— R. Colin Johnson, Advanced Technology Editor, EE Times