How were the sites for the three year rollout chosen?

Today NBN Co announced that the NBN fibre rollout plan will expand to around a third of the country’s homes and businesses over the next three years, across 1,500 communities in every state and territory, covering 3.5 million premises.

An interesting story behind the story is how these locations were chosen.

A set of logistical, engineering and practical considerations were balanced with the government’s policy objectives to determine the rollout sequence.

All of these factors were built into a mathematical algorithm, and a clever Australian company called Biarri developed the modelling into a software tool that lets us plan the most efficient sequence of areas for the rollout.

Some of the government's policy objectives that were built into the algorithm included:

• Construction should be across both rural and metropolitan areas
• Construction should be across all states and territories
• The rollout in Tasmania should be finished by 2015
• All new developments with over 100 premises should be covered

NBN Co added the following objectives

• The fixed wireless broadband rollout should be completed in 2015
• Satellite broadband via NBN Co’s own satellites should be available by 2015
• Areas where there are a large number of new developments should have priority, to avoid old technologies being installed, only to be replaced with the National Broadband Network later.

There were a set of practical considerations that factored into the algorithm, too.

While most people understandably focus on when they’ll be getting the NBN in their street, a truly more important consideration is whether there is something to connect their street back to!

We call these “transit links” (high speed cables that connect localities back to NBN Co’s core network). Transit links connect to “points of interconnect” – exchange buildings where internet and telephone providers connect their networks to ours.

NBN Co is working to complete the transit network by 2015 in order to link up all the 121 points of interconnect nationwide. That’s a large body of work going on behind the scenes during the next three years.

The progress in the installation of transit links and points of interconnect contributes to decisions about what are the most viable communities to start construction in next.

Another important design rule in building the fibre network is that where we have started construction in an area, we will complete coverage there before moving on to another area. “Fibre serving areas” are broken up into modules of around 3,000 premises, and after we start construction on one module, we complete all the modules in that area.

If construction work for your area hasn’t been announced as part of our plans for the next three years, rest assured that we’ll be updating our construction plans once a year, outlining the next series of communities in which NBN construction is scheduled to commence.