Why copper and HFC can't save us

Why copper and HFC can't save us

Summary: The Coalition is hanging onto the idea that the copper network — if we just give it a few nips and tucks — is good enough to keep us basking in 12Mbps glory for years to come. Yet a bit of work with Google Earth shows that it's a quite optimistic work of fiction to suggest that Telstra's copper and Telstra/Optus-owned HFC networks are enough to guarantee 12Mbps to everybody. Here's why.

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Of all the NBN confabulations and distortions, one of the worst is the ongoing suggestion that the copper network — if we just give it a few nips and tucks — is good enough to keep us basking in 12Mbps glory for many years to come.

Not to teach you to suck eggs, but remember that DSL technologies use specific frequency bands to transmit signals across standard copper wiring. The longer the distance the signal has to travel, the more that signal is attenuated and the slower the speed of the broadband; this is why, because I live nearly 5km as the crow flies from my local exchange, my ADSL2+ service was delivering just 2 to 3Mbps tops even though ADSL2+ is rated to 24Mbps. You will only get double-digit speeds if you live less than 3km from your local exchange; TPG, for one, offers a distance-versus-speed chart here, if you want to see how quickly speeds fall off.

Turnbull may have understood this, but he regularly misrepresents it when he says, as he did in a recent conference call with journalists, that fixing up broadband blackspots — which he identifies as the areas hobbled with Remote Integrated Multiplexers (RIMs) and pair-gain configurations and those areas housing "people living too far from exchanges to get satisfactory speeds" — can be accomplished with "quite a lot below $2 billion".

If you do a bit of playing around on Google Earth, it quickly becomes clear that there is something fundamentally wrong with the Coalition's maths and geography.

Sure, RIM and pair-gain configurations can be targeted and replaced with a government hand-out to Telstra, which should never have put them there in the first place. But I'd wager that the last group — people who live too far from exchanges to get satisfactory speeds — actually comprises quite a significant proportion of Australian households.

Thanks to ADSL2Exchanges.com.au, it's eminently possible to see just how much of a problem the copper network poses. Consider, for example, the city of Ipswich, Queensland, which I picked completely at random. Residents of Ipswich are served by one main exchange in the city's centre, the Brassall exchange 4.4km to the north, the Wallon exchange 9.6km to the west, the Amberley exchange 8.2km to the south-west, the Swanbank exchange 4.8km to the south and the exchange Bundamba, 5.8km to the east.

Telstra has, of course, sited its exchanges based on population considerations as well as the special high-density needs of locations like the RAAF Base Amberley, which lies just outside of Ipswich. Changing demographics have also changed early assumptions, with higher-density living and new population corridors putting previously unexpected pressure on exchanges. But if you do a bit of playing around on Google Earth, it quickly becomes clear that there is something fundamentally wrong with the Coalition's maths and geography.

Let's say, for rounding's sake, that everybody within 2km as the crow flies (remember that the length of copper between your house and exchange is longer than the as-the-crow-flies distance) can reach 12Mbps — meeting the Coalition's policy goal to provide "affordable broadband across the country". If we draw circles of approximately 2km radius around each exchange in the Ipswich area, we end up with a heck of a lot of areas where there is no colour. In other words, these areas are unlikely to receive 12Mbps in their wildest dreams, no matter what the Coalition does to boost their speeds. The mechanics of ADSL, and the copper-loop design choices Telstra made years ago, simply will not allow it.

Satellite view

Many residential areas in and around Ipswich are much more than 2km from local exchanges. (Screenshot by David Braue/ZDNet Australia)

Do the same in Turnbull's own electorate of Wentworth, and it's easy to see why he is so complacent: in densely-populated Sydney, exchanges are closer together and distance-generated attenuation would not seem to be such an issue, since you're rarely more than 2km from an exchange. Like Ipswich, Wentworth is serviced by six exchanges, at Vaucluse, Rose Bay, Bondi, Edgecliff, Waverley, Randwick. Plotting a 2km map around these exchanges reveals very few areas where the Coalition's dream could not plausibly come true.

Satellite image

It's hard to get more than 2km from an exchange in Malcolm Turnbull's electorate of Wentworth. (Screenshot by David Braue/ZDNet Australia)

So, perhaps, Turnbull's contention is based on the experience of his own electorate. Yet he should definitely expand his horizons: a similar map of coverage in the City of Onkaparinga, SA — one of the five NBN first-release sites — shows large areas outside our 2km boundaries. These areas may be able to get phone services at longer distances from the exchanges, but with peak theoretical speeds in the single-digit range there's a long way to go to fulfil the Coalition's dream.

Satellite image

The NBN will plug a lot of coverage holes throughout the City of Onkaparinga, SA. (Screenshot by David Braue/ZDNet Australia)

I tried the same trick in Darwin, which also has six exchanges covering its closest population centres. Again, we have massive areas where 12Mbps is simply not going to be available. The further out you go from any of our CBDs, the smaller the proportion of our country that's covered with colours. The failing here is not the copper network, but the realities of ADSL technology which might as well stand for "Additional Distance Slows Line".

Satellite image

Darwin has grown since this imagery was taken in 2006, but Telstra's exchange network only covers parts of the city well enough to deliver 12Mbps ADSL2+ services. (Screenshot by David Braue/ZDNet Australia)

These distance realities mean that no matter how many RIMs or pair-gain systems we replace, Coalition strategies are going to do basically nothing to improve service for people that already have ADSL but are simply finding that it's under-delivering. Unless Malcolm Turnbull is going to double or triple the density of Telstra's current 3000-odd exchanges around the country that is not going to change.

These realities also bode poorly for new DSL-based technologies that are now claiming to push hundreds of megabits through existing lines. Nokia Siemens Networks, for example, recently debuted noise-cancelling technology that it says can deliver 825Mbps over — wait for it — 500m of copper; this came hot on the heels of an announcement last year that NSN could deliver 25Mbps at a distance of 1.5km. Alcatel-Lucent announced a similar technology earlier in the year to provide 300Mbps over 400m of multiple aggregated copper connections.

Note first of all that these are theoretical maximums, second of all that they fall well short of resolving coverage issues past 2km, and third of all that they seem to require the use of multiple copper lines. Does your house have multiple copper lines running into it? Mine certainly doesn't.

In other words, DSL works great in laboratories over short runs of copper, but our copper network is not built using short runs of copper.

The hybrid-fibre coaxial (HFC) myth

Turnbull's other suggestion is that "we" should capitalise on Telstra's and Optus' existing cable networks to deliver 100Mbps speeds wherever possible. "You can deliver 100Mbps over the HFC network now, if it's tuned up," he said in his recent press conference. "The logical thing that would happen under the proposal I've got now, is that both of those networks would be switched up to 100Mbps."

Coalition strategies are going to do basically nothing to improve service for people that already have ADSL but are simply finding that it's under-delivering.

The thing is: the HFC networks only cover a small and carefully defined part of Australia's geography. Their networks are closed to competitors, under-subscribed and hardly at risk of being upgraded after they haven't been voluntarily extended in the past 10 years. Turnbull seems to be suggesting that the government bankroll the cost of Telstra and Optus to finish upgrading their HFC networks — yet isn't the Coalition's whole telecoms platform based on the idea that private investment will ultimately provide the services the market wants? If this is the case, why would he be stumping for subsidies to a pair of capital-city networks that are probably the best example of perfect competition the country has? Wouldn't that be a concession that the private sector just isn't interested — even in investing in wholly-owned networks over which they already have control?

Turnbull's conventional arguments against the NBN are based on a series of ever more tenuous assumptions. So when he says "if you could deliver, for example, nationwide 12Mbps at a relatively modest cost compared to the NBN, what is the additional utility benefit value of going from 12Mbps to 100Mbps?" he's deflecting the argument to be one of positioning one speed against another, when this is a false dichotomy.

That dichotomy is designed to distract from the reality: that you cannot actually deliver nationwide 12Mbps at a relatively modest cost compared to the NBN. Filling in the gaps I've highlighted would require not only the Coalition's planned RIM-replacement work, but extensive supplementation of the existing exchange infrastructure with new exchanges; billions of dollars to reroute homes' copper services from their existing distant facilities to the new sites; and all this to bolster a copper infrastructure that not even Telstra wants anymore.

Topics: NBN, Broadband, Government AU

About

Australia’s first-world economy relies on first-rate IT and telecommunications innovation. David Braue, an award-winning IT journalist and former Macworld editor, covers its challenges, successes and lessons learned as it uses ICT to assert its leadership in the developing Asia-Pacific region – and strengthen its reputation on the world stage.

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145 comments
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  • Turnbull needs to eat more veggies !
    scan06disk
  • Of course you are ignoring the fact that Telstra Countrywide trialled and approved the use of Long Line ADSL boosters that would take ADSL ranges out to 20kms from the exchange just before Sol came in and killed the idea in favour of wireless.
    Harry Tuttle
  • "That dichotomy is designed to distract from the reality: that you cannot actually deliver nationwide 12Mbps at a relatively modest cost compared to the NBN"

    Companies were lining up to build a FTTN network, which would put something like 80% of Australia within VDSL range (x0/x00 Mbps) with only $4 billion taxpayer funding.

    The remaining $24-40 billion could then be spent on carbon pollution reduction, on public transport, on health, on education -- projects that solve real problems and deliver an actual tangible benefit to society, as compared to the step-up from VDSL/FTTN to FTTP which promises only abstract hypothetical benefits. If I'm on 40/60/80/100 Mbps through a VDSL2 connection I can stream multiple high quality video sources simultaneously, and the fact is that there is no more bandwidth-intensive residential application coming through on even the most distant horizon to demand a further step up.

    Oh and HFC isn't a myth. It's a technology in the ground today which is delivering NBN or near-NBN speeds through DOCSIS 3 to users TODAY.

    "Their networks are closed to competitors, under-subscribed and hardly at risk of being upgraded after they haven't been voluntarily extended in the past 10 years."

    The roll-out was done under the assumption that Australians would take up pay-TV, which never happened to a sufficient level.

    As an physical medium for internet access, Cable has never had an advantage over ADSL which would justify users switching. So there was no point in expanding the network, as equivalent services already exist in any expansion areas.

    That is, until DOCSIS3 came through. DOCSIS3 gives HFC a competitive advantage (50-100Mbps vs 10-20Mbps) over ADSL which, for the first time since the payTV industry flopped in Australia, would justify expansion of the HFC network (assuming people actually want and demand faster speeds).

    The only reason we haven't seen this happen is because the NBN monster is hanging over the industry. There is no point in any telco laying out infrastructure (beyond relatively cheap, short-term investment such as Optus's $25m east-coast DOCSIS3 upgrade) that the government will force into redundancy to make NBNCo viable.

    "all this to bolster a copper infrastructure that not even Telstra wants anymore."

    You probably should have mentioned that there are two reasons for Telstra not "wanting" it anymore:

    1) The Government is paying an absurd amount of money for them to not "want" it
    2) The Government blackmailed Telstra by withholding the wireless spectrum they would require to be a competitive wireless player in the future unless they signed over their fixed-line assets.

    So when Telstra is presented with a choice of (a) retaining copper and being effectively banned from being a wireless provider and (b) getting a massive pay-out for their copper and being granted the required wireless spectrum, yes they "don't want copper".

    Take away the government bullying, though, and your statement doesn't hold true.
    John C-8e02f
  • David,

    Some good points. Would you be able to provide an analysis of the % of the population not covered by one of your "red dots" or HFC.

    From the Ipswich map I note that any homebuilder who decides to construct a dwelling on the eastern edge of the Amberley runway will not be able to get their 12Mbps. Good for you for highlighting the inability of current networks to provide coverage to lowly populated parts of the country.

    As a taxpayer I am more than happy to see my contributions spent on the 98th percentile corner cases.
    sydneyart
  • In a word: This.

    It's amazing how quickly access to hi-speed Internet falls off as you move into the suburbs, especially for the reasons listed above. Wireless doesn't cut it either; when it works, it works, but as more people take it up to get around the lack of an ADSL connection, you would be lucky to get a stable connection, let alone move data (which is a flaw in the wireless component in both sides' arguments, but that's another story altogether).

    Where I live, we were lucky to get 1.5Mb. At my girlfriends' parents house, we had to fight tooth and nail to get the line properly retested by Telstra, so they could get their 1.5Mb connection. It's far from high speed, and it's certainly not going to magically get quicker. And we only live 40 minutes from Brisbane - how are my out of town compatriots meant to cope?
    MKeating-63d7f
  • Why can't we get an article like this printed in the major news papers. It really does show up the lack of truth in the opposition’s technical arguments.
    The another problem with the use of HFC is that it is a Carrier-Sense Multiple Access/Collision Detection (CSMA/CD) protocol. The more connections on the current run the less access to the network you get. Just ask anyone currently on HFC. They all state that it slows down once school crowd gets on board. You may be able to get 100MB over the cable but you will not be able to transfer high volumes over it.
    .
    preston_anthony@...
  • John C

    Telstra has for the last 10+ years had a policy minimal fix when broken... NO MAINTENANCE and no proper fixes to the copper network.

    They have not wanted/looked after the CAN for over a decade, long before the NBN.

    The rest of your points is the same crap spouted by the Liberals.

    Do it once, Do it properly. DO IT WITH FIBER! (to the home :))
    kirbykia@...
  • Yeah, I remember that as my father was one of the recipients of extended ADSL when he was living on the south coast of NSW...he was 10k's from the exchange and put up with dial-up for years and then all of a sudden some Telstra techs were working in a box at the end of his street...a short time later and he was offered ADSL which he took up...of course this was a great success and then it was shelved, not to be rolled out to other locations for whatever reason...
    brokey
  • http://www.tpg.com.au/maps/

    Check that out for real speed reportings... Anything Green / Blue is below 12mbps, and the Yellow zone goes from 8-13mbps (so perhaps a significant proportion of the yellow would be below 12mbps).

    now go and click on all the different exchanges... imagine trying to patch that up to ensure everyone gets 12mbps? it's a freaking mess. Has anyone really costed this properly? Is there a Cost-Benefit-Analysis of spending money patching up a copper network so that everyone gets 12 mbps? :)

    It is my opinion that anyone who invests significant money into solutions that only provide 12mbps is wasting their money. In 20 years time do you think 12mbps is going to be enough? Heck will it be enough in 10 years time? you wanna spend X Billion upgrading it only to realise it's antiquated when you finish it?

    Let's also not forget the asymmetric nature of DSL connections. 12mbps down-stream might be enough, but 1mbps up-stream? 1mbps is crap, to put it bluntly, especially if the future productivity gains of this country are to be partly gained by 'leveraging' broadband digital networks.

    43 Billion (26 billion paid by tax-payers) over 8 years is about 3 billion of tax payers money a year, the federal budget is currently at 300 billion / year. It's 1% of our federal budget - not a huge imposition imo, even if it didn't generate a return (and they're claiming it will have a profitable return)...

    FTTP solves our digital connectivity / capacity limits exactly once for probably the next 100 years, it's the right answer. Anything else is a stop-gap measure.
    tsudo-24735750407675321797117660133375
  • find it a bit ironic to find this in your article on HFC:” Their networks are closed to competitors, under-subscribed and hardly at risk of being upgraded after they haven't been voluntarily extended in the past 10 years.”
    With the main point you draw from this is that they are closed to competitors and they haven’t been extended. The most glaring point , and most pertinent to the NBN case is that it is under subscribed. People who have has access to this type of connection haven’t taken up the opportunity for faster connections! Tell me again about the demand for this 43 billion dollar waste…..
    The best option for the coalition would be to re-look at the FTN proposal. This will help most people and cost 10 times less, with the added advantage that Conroy would have to argue against his own idea…
    cowcar@...
  • And you're conveniently ignoring the fact that those long line ADSL extenders were in fact just series linked 2 Mbps SHDSL services that could provide only high contention 1.5 Mbps max ADSL services from the final remote DSLAM. Telstra sensibly dumped the option since wireless alternatives in almost all cases would provide a superior result! Sol had nothing to do with the termination of the trial. Any engineer with a clue could see that with improvements in wireless speeds and capacity that it was out of date at the time let alone in the future.
    davmel
  • "The remaining $24-40 billion could then be spent on carbon pollution reduction, on public transport, on health, on education"

    And eventually the crappy speeds of VDSL won't be enough and the copper will degrade so much that we have to spend $26B anyway like we are doing now to rip out all those redundant nodes.
    Like any tradie knows, you get the right tool for the job or you'll end up paying more in the long run.
    Option 1 (build the FTTP NBN): Cost $26BN
    Option 2 (build a FTTN NBN then later build a FTTP NBN): Cost $5B + $26BN = $31BN
    Unfortunately narrow minded myopic people always seem to pick the cheaper option first which turns out to be the more expensive one in the long run.

    "Oh and HFC isn't a myth. It's a technology in the ground today which is delivering NBN or near-NBN speeds through DOCSIS 3 to users TODAY."

    Care to point out which HFC network provides 1000/400 Mbps services TODAY?
    2 Mbps uplink speeds are a complete joke!
    Which HFC networks provide static IP for many applications that need it?
    Which HFC networks don't cripple their network with restrictions on applications (like mail servers etc)?
    HFC networks are nothing more than consumer grade crap that are made worse with crippling restrictions (because the network operators know that their network couldn't cope without those restrictions). If HFC was anywhere near as good as the NBN then why are so many limitations put on it to limit network use?

    "You probably should have mentioned that there are two reasons for Telstra not "wanting" it anymore"
    Or the 3rd main reason that the network is costing them far too much to maintain with consumer line rentals below what it costs them to maintain and substantial decline in PSTN line revenue and increase in line disconnections so the lines degrade with no further revenue.
    davmel
  • Remember that the ultimate plan for the NBN is that it will replace the copper network, and it will not be an issue of choice. So subscription rates now, when the NBN is just one of several options available (in most cases the others are all based on Telstra copper), have nothing to do with takeup later on, when it will be the only physical connection. Competition will happen at the retail level, where ISPs will fight for customers based on things like customer service and lower-priced deals – as opposed to today, where the physical location of your house is the main determinant of what connectivity choices (or lack thereof) you have.
    braue
  • "The most glaring point , and most pertinent to the NBN case is that it is under subscribed. People who have has access to this type of connection haven’t taken up the opportunity for faster connections!"

    Look at the details before making such a false statement. BigPond refuse to sell customers a 100 Mbps DOCSIS3 service unless you bundle the most expensive line rental and mobile service in with it! It's a complete joke and abuse of their monopoly of the HFC network to demand hundreds of dollars a month if you want the highest speed. No wonder there is little take up. People want faster speeds on HFC, but they don't want to be held to ransom with useless bundling to get it.
    davmel
  • Why exactly are anecdotal evidence being used to dispute this. Not everyone has issues with the exchange.

    Furthermore you are misquoting Turnbull. 12mbit is a baseline, its technology agnostic. So that means that all the exchanges/RIM are within the areas get upgraded (this is what he meant by spending 2 billion dollars on metro areas to upgrade the RIMS). Areas that can't get 12mbits on copper won't be, in such a case fibre or wireless would be used

    Helps if you wouldn't misrepresent what he is saying, he never said that he would only use copper to deliver that 12mbit
    deteego
  • It is interesting you make the point that successful subscriptions rates for the NBN will depend on there being no other fixed line alternatives, if faced with a choice it is 50-50 if end users will opt for a FTTH solution, so much for it being the best solution, if it was the best alternative it would survive on its technical merits.

    It is not going to survive on its technical merits, it will survive (if you could call it that) because legislation will be passed to eliminate competitors and billions of dollars given to Telstra and Optus to migrate their customer base across.

    It will give a whole new meaning to the term 'forced migration'.

    The most successful communications infrastructure is wireless BB which has competing supplier infrastructures, it is successful because consumers are clamoring for the ever increasing range of products such infrastructure supports.
    advocate-d95d7
    • Wireless is no good for big uploads. Too much latency.
      Mel Sommersberg
  • Keeping that in mind, now tell us your FUDged figures again (per head/household)... and what about the upper and lower houses of parliament, tell us that too I love a good laugh!
    RS-ef540
  • So you know all about the future bundling options for the highest speed retail NBN plans from the likes of Optus, BigPond, iiNet etc do you? then made a comparison with the current BigPond 100 Mbps HFC package and decided that the NBN is the value choice.

    Amazing.
    advocate-d95d7
  • John C, the reason why the HFC network rollouts stopped was because Telstra began overbuilding the Optus HFC rollout to protect their monopoly. Neither network was viable if they were duplicated, so faced with mutually assured destruction, both stopped building.

    This is a good historical example of telecommunications market failure, and why I support the NBN. The arguments against copper have been well made in this article.
    ellermanj