Bell Labs, the research unit of Alcatel-Lucent, is claiming to have achieved data transmission speeds of 10 Gbit/s over a 30-meters length of bonded copper using a technology it is calling XG-FAST. (See Alcatel-Lucent Claims Copper Speed Record.)
The tech is an extension of G.fast, an ITU emerging standard technology (soon to be finalized) that promises theoretical speeds of up to 1 Gbit/s over the copper connection to a broadband user's premises.
Bell Labs says it achieved the 10 Gbit/s speed using an XG-FAST prototype hooked up to copper lines provided by an unidentified European telco. The test also showed the potential of XG-FAST to enable 1Gbit/s symmetrical speeds over single copper lines at a range of up to 70 meters. The Alcatel-Lucent (NYSE: ALU) unit says XG-FAST uses a frequency range of up to 500MHz, compared with the 106 MHz to be used by G.fast deployments.
Table 1: G.fast vs. XG-FAST Technology Comparison
|Technology||Frequency||Maximum aggregate speed||Maximum distance|
|VDSL2*||17MHz||150 Mbit/s||400 meters|
|G.fast phase 1*||106MHz||700 Mbit/s||100 meters|
|G.fast phase 2*||212MHz||1.25 Gbit/s||70 meters|
|Bell Labs XG-FAST**||350MHz||2 Gbit/s (1 Gbit/s symmetrical)||70 meters|
|Bell Labs XG-FAST with bonding ***||500MHz||10 Gbit/s (two pairs)||30 meters|
* Industry standard specifications. G.fast allows for upload and download speeds to be configured by the operator.
** In a laboratory, reproducing real-world conditions of distance and copper quality.
*** Laboratory conditions.
Why this matters
The further development of technologies that enable faster broadband speeds over copper is increasingly important to network operators with installed, dense copper access networks (including many, but not all, major European markets).
That's because a major chunk of the cost of deploying fiber-to-the-home (FTTH) broadband is running the fiber into homes and offices from street cabinets and other local aggregation points. Being able to take fiber close to end users and then be able to offer very fast fixed broadband services using existing sunk copper lines is extremely attractive, as it is cheaper and quicker and extends the useful life of the copper plant. (See No Easy Answers on FTTH Investment.)
While FTTH continues to be deployed around the world, the rate of deployment and uptake is relatively slow in most markets, providing a business opportunity for vendors that can boost copper broadband speeds. Alcatel-Lucent is now in a race with rivals such as Huawei Technologies Co. Ltd. to bring to market technologies that can help service providers deliver Gigabit broadband without having to take fiber plant all the way to the users' premises. (See BT Trials Huawei's G.fast for FTTx.)
— Ray Le Maistre, , Editor-in-Chief, Light Reading