In The US, Next Generation DSL Pumps 1Gbps Through Copper Phone Lines

The Next Generation of DSL Can Pump 1Gbps Through Copper Phone Lines

Well here's an interesting twist on the whole national fibre debate. We're talking the US copper network here -- a completely different beast to Australia - but let's take a look at the new US G.fast standard. It promises to deliver fibre optic speeds over their existing telephone lines.

Older iterations of DSL technology were able to provide broadband connectivity through existing telephone lines thanks to a special modulation technique that allowed voice and data to share the same wire at different frequency ranges -- DSL at 25 to 1104 KHz and voice between 30 Hz to 4 KHz. However there is only so much signal a single twisted copper cable can carry. This limits the current standard, VDSL2, to just 100 Mbps over a bandwidth of 30 MHz, though you'll be hard pressed to find an ISP that actually offers these speeds.

G.fast, on the other hand, uses a much larger 106 Mhz section of bandwidth to deliver speeds up to 1Gbps -- the same as Google Fibre. The new standard is not perfect, though, as its upper frequency range overlaps with the FM radio spectrum, which can cause interference. Plus its wide frequency range generates a large amount of cross-talk between the bundled wires themselves. And, like VDSL2 before it, ISP's could potentially cut the maximum available speed in half to just 500 Mbps due to financial and technical constraints. Still, even at half capacity G.fast is 5 times quicker than its predecessors.

The G.fast standard is expected to be finalised some time next year and could begin rolling out to everywhere Google Fibre and Verizon Fios aren't by the start of 2016. Don't ditch your land line just yet. [Extreme Tech - Huawei - Image: ULKASTUDIO]