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NBN Co flicks switch on transit capacity upgrade

25 September 2018

Upgrades will help double capacity on 60,000km transit fibre network

NBN Co, the company building Australia’s wholesale broadband access network, has switched on a major upgrade to double bandwidth capacity on its 60,000km fibre optic backbone that will help deliver broadband services to a larger customer base with a bigger appetite for data.

The upgrade means NBN Co can increase maximum capacity on its transit network from 9.6 Terabits per second (Tbps) to 19.2Tbps per fibre link, which will help meet the broadband needs of homes and businesses into the future.

The first upgrades will span high-traffic fibre links between Eastern Creek and Asquith in Sydney, and the 3,600km route between Brisbane, Queensland and Darwin in the Northern Territory. There will then be a phased rollout across the rest of the country.

The Sydney link will provide extra capacity as bandwidth demands continue to grow. The Darwin to Brisbane link is scheduled to go live in December and will support capacity growth on NBN Co’s Sky Muster™ satellite network.

NBN Co’s transit network is a backbone network of fibre optic cables that links hubs across Australia to the wider nbn™ broadband access network that connects homes and businesses. It’s the network that moves large aggregate volumes of data between locations – helping get capacity get to homes and businesses.

It connects to NBN’s 121 Points of Interconnection (POIs) – typically located at telephone exchanges – which is where phone and internet providers plug their own network into the nbn™ access network.

The capacity upgrade has been made possible with the successful installation of new optical transmission technology - from network equipment maker Coriant’s CloudWave Optics - that supports per-wavelength transmission rates of 200 gigabits per second (Gbps) on optical transport backbone networks. The new technology has the capability to be upgraded to 400Gbps when needed.

NBN Co will deploy the new technology at POI sites, large fibre access nodes and highly trafficked routes as demand dictates.

NBN Co's Chief Network Deployment Officer, Kathrine Dyer said:

“Our transit network is the backbone of the nbn™ multi-technology mix that aims to provide Australians with access to fast services*.”

“This upgrade will ensure we can continue to deliver a reliable and high-quality broadband network for our wholesale customers even as high-bandwidth applications and the growth of internet usage continue to drive demand for network capacity.”

“We have a clear product roadmap to continually upgrade this network with extra capacity as demand grows. With the upgrade to CloudWave Optics technology, we will be able to further increase total capacity on our Transit network. Coriant is helping us achieve these upgrades as we scale this build and move towards our goal of connecting eight million homes and businesses by 2020."


* Your experience, including the speeds actually achieved over the nbn™ network, depends on the nbn™ access network technology and configuration over which services are delivered to your premises, whether you are using the internet during the busy period, and some factors outside our control (like your equipment quality, software, broadband plans, signal reception and how your service provider designs its network). Speeds may be impacted by network congestion on nbn’s Fixed Wireless network, including during busy periods. Satellite users may experience latency.

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Mitchell Bingemann

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