Bill Morrow has outlined some of the ways in which the Government's much-touted mixed technology rollout approach is hampering NBN performance

Bill Morrow - CEO, nbn

Speed limitations, increased fault rate and operating costs, and a lengthy co-existence period are among the consequences of the Government’s much-touted mixed technology rollout for the National Broadband Network (NBN), according to NBN Co chief Bill Morrow.

In a new position paper, seen by ARN, Morrow has outlined the technical basis for a number of the service issues experienced by end customers of the network, much of which stems from the legacy infrastructure being used under the Federal Government’s preferred multi-technology mix (MTM) model for the network’s rollout.

“While the use of the existing copper and pay TV networks has led to a faster network build and a lower cost-per-premises, there are consequences to this approach,” Morrow said in the position paper.

“The first and most notable consequence is the maximum speed limitations of copper versus the previous fibre-based model.

“A second consequence of the use of copper in the last (approximately) 1km of the network is the increased fault rate and operating costs versus the all-fibre alternative,” he said, stressing that these costs remain less than those of a mostly-fibre alternative, and that the incremental fault rate was felt to be within reason.

A third consequence of the Government’s expanded MTM rollout, according to Morrow, is related to the ‘co-existence period’ – a contracted period that begins when NBN Co declares an area ready for service.

“While in the co-existence period, NBN Co is responsible for operating and maintaining all services over the network, including any Telstra legacy services provided by that portion of the network,” Morrow said.

“While this is all technically achievable, the sharing of the spectrum requires NBN Co to adjust and plan for earlier network capacity enhancements,” he said.

The trade-offs of using existing infrastructure to reduce the cost and the time of the NBN rollout do not stop there, with Morrow also suggesting that, for each of the pre-existing infrastructures, the physical condition of the network is sometimes worse than anticipated.

"Additionally, the databases of what exists and where each network is located are sometimes absent or inaccurate. These factors have created additional challenges," Morrow said.

The comments, which arrive just weeks after Morrow announced his resignation from the leadership of NBN Co, come as the network and the company behind its rollout weather heavy scrutiny by the public and other stakeholders due to ongoing connection and performance issues.

Morrow’s latest position paper appears to make an effort to illustrate the key reasons behind some of the core issues raised by consumers while defending many of the decisions behind the network’s technology footprint and business model, both of which have met with criticism from certain quarters.

A largely optical fibre-based network drawing heavily on Fibre-to-the-Premises (FttP) technology was the previous Labor Government’s preference for the project as it was initially introduced in 2007.

The move away from a fibre-heavy network to an ostensibly more affordable MTM approach was a major point of difference between the incumbent Labor Government, and the Liberal-National Coalition, which ultimately won the country’s vote.

In late 2013, at the direction of the then newly-appointed Australian Government, NBN Co conducted a strategic review to assess and select alternative approaches that would improve the commercial viability and time to complete nationwide access to high-speed broadband.

While the original design had three access technologies in the mix, NBN Co and the newly-appointed Australian Government decided to add two additional access technologies: Fibre-to- the-Node (FttN) and Hybrid Fibre-Coaxial (HFC).

As reported by News Limited, the new position paper sees Morrow highlight the speed limitations arising from the use of Telstra’s existing copper network in the FttN footprint.

The HFC network, meanwhile, has experienced problems of its own, with Morrow announcing late last year a temporary pause in new HFC network services due to technical issues.

However, despite highlighting the intrinsic drawbacks of the MTM’s reliance on legacy infrastructure like Telstra's copper and HFC networks, Morrow remains optimistic that the rollout will meet its key objectives.

“Whether NBN Co uses the former three-technology MTM or the current seven-technology MTM, the nation will have universal access to the minimum defined service levels,” he said.

At the same time, Morrow cautioned that, as Australians opt for higher performance services, a technology-determined divide may emerge.

“As NBN Co compares the high end of the available services, there will be a greater level of difference. This difference depends on which technology is serving an end-user’s home or business,” he said.