The slow march away from the dwindling supply of Internet Protocol (IP) version 4 addresses to IPv6 addresses continues, with Telstra announcing that its business ADSL products are capable of supporting IPv6.

Telstra has already completed core network upgrades for IPv6, and has allowed Telstra Internet Direct enterprise and government as well as Telstra Next IP VPN customers to take up IPv6 since 2011, but the company announced yesterday that IPv6 is now available for business ADSL customers.

Telstra's director of transport and routing engineering David Robertson said that Telstra has a long-term road map for migration to IPv6, and IPv6 would be more widely available in the future.

"The deployment of IPv6 into Telstra's network is an on-going program of work, and we'll make this available for other services such as fixed consumer and our wireless networks over time," he said in a statement.

Telstra has opted to dual stack IPv4 and IPv6, meaning that customers can move onto IPv6 within their buying cycle without being forced to upgrade early.

But Robertson said that the day will come when customers will have to opt out to avoid switching to IPv6.

"In coming years, we expect that IPv6 will become the norm, and customers will need to opt out if they wish to use IPv4," he said. "However, as we start this transition, we'll be working directly with customers to support them as they make this change."

In Australia, iiNet-owned internet service provider (ISP) Internode has led the charge on IPv6 . On the first anniversary of IPv6 launch day earlier this month, the company reported that 10 percent of its customers are now on IPv6, up from 2 percent in June 2012.