Angling to join the growing gigabit parade around the world, NBN plans to offer cable's next-gen DOCSIS 3.1 service over its hybrid fiber-coax (HFC) lines in Australia, starting early next spring.

NBN Co Ltd. -- the government-backed entity that is taking over control of Australia's privately built broadband networks under deals struck in December with Telstra Corp. Ltd. (ASX: TLS; NZK: TLS) and Optus Administration Pty. Ltd. -- announced the commitment at the Cable Congress conference in Brussels Thursday. The company said it will roll out DOCSIS 3.1 technology to more than 3.3 million homes and businesses in major Australian markets over its HFC networks, which will cover about 28% of its total potential footprint of 12.4 million premises.

With the move, NBN will join North America's largest cable operator, Comcast Corp. (Nasdaq: CMCSA, CMCSK), and Europe's largest MSO, Liberty Global Inc. (Nasdaq: LBTY), in embracing the new broadband standard from CableLabs . Several other major cable operators, such as Cox Communications Inc. , have also indicated that they expect to deploy DOCSIS 3.1, which is designed to enable download speeds as high as 10 Gbit/s and upload speeds of 1 Gbit/s or more.

In an interview with Light Reading, NBN CTO Dennis Steiger said the company plans to start conducting construction and field trials by the end of this year, with the goal of launching service commercially by next March. Plans call for offering the service to broadband subscribers in Adelaide, Brisbane, Melbourne, Perth, Sydney and the Gold Coast. NBN aims to extend DOCSIS 3.1 service to its entire HFC footprint by the end of 2019.

NBN plans to spend about $20 million upgrading its HFC networks for DOCSIS 3.1 readiness. But Steiger expects the bandwidth efficiencies gained to at least offset that cost, making it a "self-funding" project. "We're really big proponents of it [DOCSIS 3.1]," he said. "For us, it's really all about the bandwidth efficiencies."

As reported last month, NBN will at least initially rely on infrastructure support from Arris Group Inc. (Nasdaq: ARRS) for the DOCSIS 3.1 rollout, employing the vendor's CCAP-enabled E6000 Converged Edge Router and other key network equipment. Arris saw off Cisco Systems Inc. (Nasdaq: CSCO) for the contract, at least partly because the Australian company felt it couldn't wait for Cisco to introduce the cBR-8, its late-to-market entry in the rapidly growing market for next-gen Converged Cable Access Platform (CCAP) equipment in the cable headend. (See Is OpenConfig a New IP Model? and Did Arris Just Upend Cisco for Major Oz Deal?.)

Want to learn more about DOCSIS 3.1 and cable's other new broadband services and technologies? Then check out the agenda for our upcoming Cable Next-Gen Technologies & Strategies event, next Tuesday, March 17, 2015, at The Cable Center in Denver.

Unlike in most other regions of the world, Steiger explained that NBN's retail service partners (RSPs) in each market will supply the cable modem and gateways to broadband subscribers, not his company. He hopes new 3.1 modems and gateways will start showing up in Australia later this year, although he expects that the RSPs may start with 3.0 devices while the vendors gear up with 3.1 equipment.

NBN will still certify all the modems and other devices used by its partners. Steiger expects the new 3.1 modems to cost about $10 to $15 apiece more than today's 3.0 modems for about the first 18 months, then drop down in price to the same level as now.

With the DOCSIS 3.1 lab, field and customer trials still looming ahead of NBN, Steiger said he's expecting to run into some implementation problems. "We still have to prove out the technology," he said. "We have to make sure the technology actually works in the real world. I'm sure there will be some bugs to work through."

But Steiger seems confident that the technology will pass muster. He noted that the interoperability testing of DOCSIS 3.1 cable modems and cable modem termination systems (CMTSs) by CableLabs has proven to be promising so far.

While the deployment of DOCSIS 3.1 will technically enable NBN to offer much higher broadband speeds over HFC than it can today, Steiger said the company will likely come "right out of the gate" with maximum download speeds of just 100 Mbit/s, not 1 Gbit/s or more, and then bide its time until customer demand builds. "We haven't talked about going beyond that [100 Mbit/s] yet," he said. "There isn't a lot of demand for gigabit service."

— Alan Breznick, Cable/Video Practice Leader, Light Reading