NBN Co revealed this morning that it had deployed the first G-fast-capable distribution point units (DPUs) as part of its roll out of fibre to the curb (FTTC).
The dual-mode DPUs have been installed in the Sydney suburb of Rockdale as part of a trial, with the units supporting both the ultra-fast G.fast standard and the VDSL2 standard currently used to deliver FTTC services to end users. For the time being, the new DPUs will continue operating in VDSL2 mode, however, with NBN Co not planning to immediately switch to the faster standard.
FTTC uses more optical fibre than fibre to the node (FTTN) but still relies on the existing copper line for a final connection to a home or business. The DPU sits in a nearby telecoms pit and acts as the point of interface between fibre and copper (unlike FTTN, the necessary power is drawn from the end user's premises, rather than an on-street cabinet).
G.fast is capable of delivering ultra-fast speeds over short lengths of copper. The first version of the International Telecommunications Union standard, released in 2014, promised up to 1 gigabit per second; a later revision of the standard envisages speeds of up to 2Gpbs
G.fast employs frequencies up to 212MHz, whereas VDSL2, which is being used for FTTN as well as FTTC, tops out at 17MHz. While the lengths of copper used for NBN Co’s FTTN service average about 450 metres, FTTC connections average 40 metres — making the technology a prime candidate for G.fast.
Chief network engineering officer Peter Ryan said that NBN Co was the first network operator to deliver G.fast capabilities using in-ground DPUs.
“To put it plainly, G.fast gives us the ability to deliver greater speeds to end users who are connected to the nbn broadband access network on our FTTC technology,” Ryan wrote in a blog entry.
“Although other global operators such as Openreach in the UK, SK Broadband in South Korea and Swisscom in Switzerland have already deployed G.fast, they have deployed the protocol standard from their existing Fibre-to-the-Node street cabinets.”
NBN Co earlier this year launched commercial FTTC services. The company’s planned deployment of the technology has expanded dramatically since it first began trials of it in 2016. Currently, some 1 million premises are expected to be connected using FTTC.
NBN Co is sourcing G.fast-capable DPUs from Nokia and ADTRAN (along with Netcomm Wireless the companies have supplied the DPUs used so far in the FTTC rollout). Previously, the DPUs deployed by NBN Co only supported theoretical maximum speeds of 100/40 megabits per second.
Nokia said the DPUs it had supplied could be remotely switched to G.fast when necessary. The technology will allow NBN Co to deliver close to 2Gbps aggregate upstream and downstream speeds, Nokia said.
“NBN is well on its way to meeting its mass deployment goals to deliver super-fast broadband to every home and business across Australia,” said Nokia’s head of Oceania, Zoltan Losteiner.
“Nokia is very proud to have been part of this journey and to employ our unique insight to help NBN best plan its future network evolution. NBN has the benefit of open evolution pathways in each of its network domains and the deployment of G.fast is a key milestone in the capability of its FTTC network.”
Nokia is expected to have delivered almost 50,000 G.fast-capable 4-port DPUs to NBN Co by the end of 2018.
“ADTRAN is proud to be a partner in this exciting project, which has shown how the NBN – in eight short years – has already contributed significantly to the economy and social wellbeing of millions of Australians,” said ADTRAN EMEA/APAC chief technology officer Ronan Kelly.
Ryan said that NBN Co had no “immediate plans” to launch services that took advantage of the higher maximum speeds of G.fast because residential demand was being met by its existing 50Mbps and 100Mbps speed tiers.
“However, putting G.fast capability in the ground now is a future-proofing step,” the NBN Co executive wrote. “Down the track, all we need do is enable the protocol standard remotely and issue relevant end users with a new G.fast-capable modem. These premises will then have access to the ultra-fast speeds that G.fast can deliver.
“It makes economic sense for NBN Co to hold off providing G.fast services until there are sufficient market signals from phone and internet providers for us to proceed. After all, there is no sense in us offering ultra-fast G.fast wholesale services until end user demand is there to buy them.”
Last month NBN Co launched Enterprise Ethernet services, offering up to 1Gbps to businesses.