LONDON -- Broadband World Forum -- Having already received a major boost from the UK's BT, G.fast technology could also figure prominently in the plans of Australia's NBN, which has just announced field trials of the copper-based technology in partnership with Alcatel-Lucent. (See Long-Range, High-Speed Gfast Is Coming – BT.)

The state-backed operator, which is building a nationwide wholesale network using the full array of broadband technologies, reckons G.fast could minimize the disruption and cost of rolling out fiber.

G.fast improves the performance of last-mile copper connections by extending the frequency range over which signals travel, although it loses effectiveness over longer distances.

Currently, NBN Co Ltd. 's plans are to use fiber-to-the-premises (FTTP) for 20% of its rollout, hybrid fiber-coax (HFC) for another 34% and fiber-to-the-node (FTTN) or fiber-to-the-basement (FTTB) technology for about 38%. Customers in those hard-to-reach areas accounting for the final 8% will be served using fixed wireless and satellite systems. (See Australia's NBN Launches FTTB Service and NBN Digs a Hole for Itself.)

During its G.fast field trials with Alcatel-Lucent (NYSE: ALU), NBN claims to have achieved connection speeds of about 600 Mbit/s at a distance of around 100 meters. "We will probably see trials with retail service providers in 2016 and a 2017 commercial service," said Tony Cross, NBN's chief architect, during an interview with Light Reading at this week's Broadband World Forum in London.

By 2017, NBN expects to have completed most of the FTTP deployment, but G.fast could have a major role to play in the FTTN/FTTB area, allowing the operator to provide higher-speed services to customers on these networks.

To boost speeds, the alternative to installing a G.fast distribution point near customer premises would be more costly civil engineering works or in-building rewiring, which has already triggered a backlash from landlords and property owners. "If we can avoid crossing the property boundary, we have avoided a lot of hassle," says Tony Brown, NBN's public affairs manager.

Yet G.fast could prove very controversial in this context because it would require NBN to invest more funds in extending fiber to its local distribution points.

The public-sector cost implications of the NBN project have provoked consternation in Australia and in August the country's government capped its investment in NBN at A$29.5 billion ($21.3 billion), leaving the operator with a gaping black hole in its finances. (See Australia's NBN Cost Blowout.)

Reports at the time indicated the company would need to raise as much as A$26.5 billion ($19.2 billion) from the private sector to complete its network rollout.

NBN could avoid extending fiber networks by mimicking the approach of BT, the UK's fixed-line incumbent, and deploying G.fast at street cabinets, but this could prove difficult.

BT's optimism about deploying G.fast from the cabinet has been fueled by signs that hardware is becoming more capable: Earlier this week, the operator said 96-port distribution point units and more advanced chipsets were appearing on the roadmaps of equipment vendors.

But a 96-port unit would probably not be enough for NBN to use G.fast over much longer distances, acknowledges Cross. "We are installing 384-port devices in the node and it will be a while before G.fast can do that, so taking out VDSL and putting G.fast in at that location isn't going to be realistic," says Cross.

NBN needs much bigger port numbers/boxes than operators in many other parts of the world because of its position as Australia's main infrastructure player and wholesale-only service provider.

"BT will take a 16-port unit and place it where there are 50 or 60 lines at that juncture and it's going for 20% take-up, and that makes good sense," says Cross. "In that same location, we would be going for 70% penetration and therefore need units that are three or four times bigger."

The rollout of gigabit broadband access networks is spreading. Find out what's happening where in our dedicated Gigabit Cities content channel here on Light Reading.

Nevertheless, Cross agrees that a 96-port unit would be "helpful" and could be used to "augment" the service that NBN provides, adding to the pressure on G.fast vendors to come up with even more advanced products.

"The NBN is kind of flushing out what the demand is for higher speeds," elaborates Brown. "Only 17% of subscribers have been ordering our 100Mbit/s service and so we wouldn't need that [96-port unit] to serve everyone, but maybe in industrial parks or upscale areas where people want high-speed broadband."

NBN has yet, however, to formulate any firm plans regarding a commercial deployment of G.fast.

Cross tells Light Reading that NBN also has an eye on XG.FAST, an in-development technology that BT has been trialing with Alcatel-Lucent. "We will look at everything and use it where it makes sense," he says.

Having taken ownership of network infrastructure previously controlled by Telstra Corp. Ltd. (ASX: TLS; NZK: TLS) and Optus Administration Pty. Ltd. , Australia's two largest network operators, NBN now claims to have passed about 1.3 million of Australia's 12 million premises with its various network architectures and connected around 550,000 customers.

That includes 200,000 on its FTTN network but Cross expects this number to soar to about 3.7 million by June 2018.

— Iain Morris, , News Editor, Light Reading