NBN Co has begun work on support for Internet Protocol version 6 (IPv6) for Layer 3 protocols on the National Broadband Network, with the first elements expected to become available next year.
Though the NBN is primarily a Layer 2 network - solely providing the data link to end-users - it plans to offer some Layer 3 network services including multicast, SIP telephony and quality of service.
It would offer preliminary support for IPv6 on its quality of service offering next year, allowing service providers to identify user traffic by telephony, video, data and basic web browsing.
It would also implement a lightweight DHCP relay agent, a feature of DHCPv6 that identified a service provider's subscribers using Internet Protocol over Ethernet (IPoE), next April.
Support for telephony would come the following year but required a firmware update to the network termination unit (NTU) being installed in homes as part of the network rollout.
As the NTU provided two telephony ports, NBN Co planned to allow a transition to IPv6 separately and independently of each other, depending on the service provider's roadmap.
Solutions architect Tom Sykes said the box's design had been a challenge in planning protocol support.
"These boxes aren't built for open access; they're built for one, vertically integrated telco who moves the entire box between v4 and v6 at once. We don't have that luxury," he said at the Australian Network Operators Group (AusNOG) 2011 conference last week.
"We can't be involved in setting the end-date for the v6/v4 migration and the reason we're taking so long to do this is because we've made these ATA ports run independently."
Protocol support for multicast would also be offered by 2013 but Sykes said interest for the capability from service providers had so far been lacking.
Though support for the protocol in multicast was not expected to provide any significant new features, it would still be required by service providers lacking IPv4 addresses for new users.
Planning support for the protocol had come as a challenge to NBN Co.
Sykes said the company remained uncertain on exact dates and transition plans for access seekers.
"You can't set a date with 30 service providers and say, 'Right. We're transitioning at this point in time'," he said. "How do we build the network as such that each service provider has the freedom to transition, or not, at their own leisure?"
He appealed to providers at the conference to provide greater feedback on when and how they required IPv6 support for particular products to allow the wholesaler to refine its product roadmap.