NBN Co in 'broadband kit we tested worked' STUNNER NBN Co, the entity charged with building and operating Australia's National Broadband Network (NBN), has let world+dog know that one test of VDSL delivered over fibre-to-the-node (FTTN) worked. You can read the announcement here if you want: it explains that the test achieved “delivered raw download speeds of 105 megabits per …
Ever since the LNP decided not to kill the NBN in favour of somehow spending the money they wouldn't save on flood relief, infrastructure or bribing the very rich into bearing children, they've been really hot on the idea of vectored VDSL replacing FTTP.
Turnbull's big claim was that vectored VDSL would allow punters to get up to 100Mb/sec out of their waterlogged copper pairs, so they'll be really stoked to see NBNCo getting these numbers out in front of voters. But vectoring is done on the node end to reduce the effects of crosstalk, and it's not hard to see how a single active VDSL pair is not going to see a lot of crosstalk from VDSL traffic on adjacent pairs.
It would be a lot more reassuring to see a successful demonstration of multiple active pairs running closer to the maximum specified distance between a node and end user premises.
We've already got VDSL available as a consumer product in NZ after the big FTTN roll-out a few years ago. It's a good solution for those within about 700m of the cabinet who don't have fibre yet, but any further out, unless your line quality is very good, the application usually gets rejected by the provider.
The people nearest the cabinet can get up to 70/30 MB/s, those further away get 30/10 speeds.
The high frequencies of VDSL makes it very susceptible to the problem of crosstalk interference, meaning the more people who have it the worse the performance gets for everyone else, especially when the lines aren't top quality. A Tragedy of the Commons situation which fibre largely avoids.
And only today even The Age (*) is commenting about brain drain in Australia:
http://www.theage.com.au/business/startups-starved-of-venture-capital-20140421-370ck.html
They blame it on lack of VC, but gee, I wonder if utter lack of support for technology in terms of infrastructure might also be to blame.
(*) Paywall or Greasemonkey, take your pick
Umm ... of course it "works" but at rapidly reducing speed the further you are from cabinet and the more pairs in a multi-pair cable that are active. More than 200m and coax DOCSIS 3.0 from cabinet makes more sense than copper. At 1km no better than ADSL2+
For a minimum 100Mbps from cabinet you need DOCSIS (Cable). For low contention and / or more than 100Mbps you need FTTP/FTTH. Fibre to node is an interim solution and only good for Urban. Or for Cable Operators (HFC). Any new fibre system today should be FTTP/FTTH
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