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This Gigabit Broadband Still Makes Use of Old Copper Wires

A little bit of it, anyway.
September 25, 2014, 5:05pm

When it comes to broadband, the only real sex appeal is speed. Whatever your provider, all you really want to know is how many megabits per second (Mbps) you're getting. Or, if you're a real broadband boy racer, gigabits (Gbps).

BT, the UK's multinational telecoms company, claims to have made a breakthrough in reaching those gigabit-per-second speed—without completely relinquishing the old copper network.

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To get ultrafast speeds, you'd usually expect to use fibre optic all the way to your residence—a fibre to the home, or FTTH system (also sometimes called FTTP or fibre to the premises). But a lot of the country is still wired up with copper phone lines.

Because the copper network is already there, and it's much cheaper to use that as a base than lay new fibres to everyone's homes and offices, most broadband uses a fibre to the cabinet (FTTC) system. Fibre goes as far as the nearest street cabinet, where it connects to your home via the existing copper. And that's slower.

But according to BT, they've cracked a way of reaching ultrafast speeds while keeping some copper in the mix. Trials of their "G.Fast" technology gave a combined upload and download speed of up to one Gigabit per second.

A street cabinet, where fibre connects with copper in FTTC systems. Image: Flickr/Mike Cattell

G.Fast is basically a compromise between FTTC and FTTH. It quite simply takes fibre further than the cabinet, but not quite as far as the home. The fibre is extended to a telephone pole or junction box somewhere between the cabinet and your home, in what's called "Fibre To The Distribution Point," or FTTdp.

"G.FAST technology is then used to maximise data capacity over the copper and uses much higher frequencies, plus advanced 'crosstalk' cancellation techniques, to make ultrafast speeds possible," BT wrote.

Unsurprisingly, where the copper section was shortest, they got the fastest speeds. But even when the copper stretched up to 66m—not an inconsiderable distance—they recorded around 900 Mbps. BT said this distance would encompass 80 percent of connections.

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Of course, that still leaves a chunky minority of connections that won't benefit from the fastest speeds, not to mention there are still parts of the country, especially rural areas, that are still suffering with a few measly megabits. According to mobile news site Recombu, rural areas are less likely to benefit from G.Fast because their "last mile"—the remaining copper line—is naturally often longer.

You avoid entering the home, and for some operators this is a very important factor.

The UK government has promised at least 24 Mbps to 95 percent of the population by 2017, but that remaining five percent are unlikely to be comforted by the knowledge some of the majority are getting speeds 40 times that minimum level.

Given the fact that the closer you get to the home with fibre, the faster the speeds, the question becomes whether it's not just best to cut your losses and take fibre all the way, as in FTTH. But discussing G.Fast with ISPreview last year, the director of comms from French telecom company Alcatel-Lucent explained that it's not about saving the cost of the fibre itself, but of the disruption of getting access to individual properties.

"You avoid entering the home, and for some operators this is a very important factor and a very costly and time-consuming part of the roll-out," he said.

G.Fast hasn't yet been standardised, but the BBC reports that it could be in operation by the end of next year. Of course, if you can't wait, you could just start building your own fibre network.