This could be the last time Australians need to ask a friend for their Wi-Fi password. The country’s biggest telco has announced it will build one of the world’s biggest Wi-Fi networks, in part by asking its broadband customers to share a “portion” of their bandwidth to create public hotspots.

The massive wireless project will see Telstra roll out new modems to almost two million homes and businesses to serve as one interconnected public Wi-Fi network.

At the launch in Sydney yesterday, CEO David Thodey said Telstra would spend AU$100 million (US$92 million) building 8,000 Wi-Fi hotspots in shopping areas, business centres and transport hubs over the next five years.

Those that opt-in to the “Wi-Fi nation” and allow others to connect with their home routers will be able to use their broadband allowance at no extra charge across the domestic network, as well as more than 12 million ‘Fon’-enabled hotspots globally.

Thodey said the public Wi-Fi network would not affect a customer’s home speeds and that users should expect download speeds of about 2 megabits per second — enough to stream a high definition movie — over the new network.

The success of the opt-in scheme, which is expected to launch early next year, will depend on Telstra persuading its customers to open up their networks.

Telstra said the public access side of a customer’s home router would have “normal Wi-Fi security”. Users would retain their own login details and have data charged to their own account no matter which hotspot they access, Thodey said.

The announcement represents a backflip for Telstra, which shut down its previous national network of wireless hot spots in 2011 due to a lack of profit. A spokesperson for the telco told iTnews at the time, customers “prefer[red] the convenience of…mobile broadband.”

But Thodey insists the way Australians accessed the Internet had “fundamentally changed” – pointing to a hunger for more data-intensive content such as videos.

Mobile data traffic is forecast to grow ten-fold to more than 90,000PB (petabytes) by 2017, according to a Juniper Research report – equivalent to almost 42 quadrillion tweets.

The report anticipates up to 60 per cent of mobile data will soon be “offloaded” to Wi-Fi and small cell networks to ease the overstretched cellular networks.

Wi-Fi networks, which typically use fixed copper and fibre to carry signals to carry web traffic to and from telephone exchanges, can generally handle higher speeds and larger traffic loads than 3G and 4G networks which use mobile phone towers.

Residents of the Japanese city of Osaka, like those in hundreds of cities worldwide, are offering portions of their home and business Wi-Fi bandwidth to the public. Pic: Fon.

A city centre of overlapping hotspots – such as the Fon network that already exists in cities like Osaka – would also reduce the incidence of network overload that often affects users in Australian cities during major sporting or cultural events.

If the project succeeds, Telstra could own one of the largest Wi-Fi networks in the world. Thodey said the network had been made possible through advances in Wi-Fi technology that allowed far better data capacity and much better coverage within buildings.

“We think now is the right time,” he said.