Darwin prepares for cheaper broadband

The cable

Linked gallery: Photos: Nextgen completes national backhaul

Nextgen are set to transition to operation and commercialisation mode on the national backhaul segments from early next year, once final audits and paperwork is complete.

The initial government tender in 2009 names Nextgen the sole wholesaler of the backhaul until 2017, but a spokesman for the Department of Broadband, Communications and the Digital Economy confirmed it plans to retain ownership rather than privatise the cable.

The cable took more than a million man hours to build, according to Sykes, with a total 1000 workers and 15 cable plowing crews working simultaneously on the build over 22 months.

Cable construction was hit by massive rainfall trenches, forcing delays of up to three months on some paths over the course of the work, including on the Darwin to Tennant Creek stretch.

"Virtually every segment of our network had rainfall of 50 percent, sometimes 100 percent of the average," Sykes said.

"It's almost as if someone said 'where can I put the rainfall over Australia' and they dropped it over our entire network.

"It was really like a large chess board; as weather conditions in one area became unfavourable, resources would be moved into another area of the network."

Nextgen took two days to repair a break to its own fibre backhaul network during the Queensland floods, but Sykes said repair crews at points along the RBBP cable should now be able to fix any breaks within eight hours.

Most links are physically redundant, allowing the operator to switch to another cable immediately.

However, one of the network's potentially most important links - Darwin to Tennant Creek - provides  a single fibre tail which would fail in the event of a cut to the physical fibre.

Sykes assured the relative population density in those areas meant repairs would be quicker than the usual eight hours.

The network is also set to receive significant bandwidth upgrades. Initially built to support 10 Gbps DWDM (Dense Wavelength Division Multiplexing) technology, the company has plans to move up to 40 Gbps once growth forecasts are met in two years' time.

Nextgen has also trialled 100 Gbps DWDM technology on the link using Alcatel-Lucent technology but intends to wait until the technology is cheaper before rolling it out.