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DSL-Extender Brings Broadband 20km

An anonymous reader writes "Whirlpool outlines Telstra's new DSL deployment: "Telstra announced a trial of the technology back in January, saying it would allow DSL to be connected to people who were up to 20km from a central exchange. DSL Extenders work by splitting an existing copper phone line into eight separate ADSL lines using a tiny, ruggedised remote DSLAM.""

30 of 149 comments (clear)

  1. Remote DSLAMs by Phroggy · · Score: 4, Informative

    Remote DSLAMs are certainly nothing new, but usually the connection from the remote DSLAM to the CO is fiber, not copper.

    Newer housing developments sometimes have a fiber line that runs into the neighborhood, then copper lines from there to each house, so the phone company doesn't have to run a big bundle of copper all the way back to the CO; a remote DSLAM is the only way to offer DSL to these houses.

    What I want to know is, how did they get a reliable 2.3Mbps link to work over 20km of copper?

    --
    $x='S24;r)>63/* h@<5+oZ)32"5cz';$me='phroggy'x$];
    $x=~y+ -xz+\0-Tx+;print$_^chop$me for split'',$x;
    1. Re:Remote DSLAMs by el_womble · · Score: 5, Interesting

      This has always struck me as stupid.

      Copper: great for POTS, crap for data, ubiquitous. So they invent DSL to compensate for copper's inadequacies.

      Fiber: crap for POTS, great for data, ubiquitous right up until the end of the street. DSL doesn't work because its a copper technology, so these poor people who are feet away from all the broadband they could ever need can't access it because telcos only know how to do DSL.

      I'm not oblivious to the fact that it costs more to split fiber (light doesn't split like electricty), but thats because we don't do it very often as the priority has always been POTS. How long will it be, now that data outweighs POTS, until we get fiber to the front door?

      --
      Scared of flying, pointy things snce 1979!
    2. Re:Remote DSLAMs by Macfox · · Score: 4, Informative

      Telstra are already using this MINIMUX technology. In many new housing estates they have installed RIM units (on the cheap) where there wasn't enough copper back to the exchange.

      When the residents discovered they couldn't get ADSL in the brand new mega expensive developments, Telstra backflipped and took two years to addressed the issue with the so called MINIMUX (Mini DSLAM). They're still rolling them out as we speak.

      Having said that, even if your on a RIM voice service, you can't get access to other providers, only Telstra (wholesale). So you're still at the mercy of Telstra's premium pricing.

      --
      Area51 - We are watching...
    3. Re:Remote DSLAMs by elgatozorbas · · Score: 4, Informative
      Copper: great for POTS, crap for data, ubiquitous. So they invent DSL to compensate for copper's inadequacies.

      They invent DSL because copper is ubiquitous. Why do you think the fiber was put there in the first place? Exactly to have a headend for either DSL or cable.

      Fiber: crap for POTS, great for data, ubiquitous right up until the end of the street. DSL doesn't work because its a copper technology, so these poor people who are feet away from all the broadband they could ever need can't access it because telcos only know how to do DSL.

      In a FTTC (fiber to the curb) system the DSL modems are right in the cabinet at the end of the fiber you mentioned.

      I'm not oblivious to the fact that it costs more to split fiber (light doesn't split like electricty), but thats because we don't do it very often as the priority has always been POTS. How long will it be, now that data outweighs POTS, until we get fiber to the front door?

      The problem is not technological in nature: neither light nor electricity is 'split'. The connections are point-to-point (between modem and DSLAM), so there is no splitting involved. The real cost is in guys digging trenches to put the fiber (and obviously the fiber and installations themselves).

    4. Re:Remote DSLAMs by Anonymous Coward · · Score: 3, Informative

      In the USA, most existing DSLAMS are connected over copper. It was initially a way to avoid 'copper starvation' during buildouts in developed areas. Instead of feeding new trunk lines out from the CO, you drop a pedestal and split two pair among 24 or 48 POTs lines. Pair gain, in the sense that two pair carriers now become 48 pair at the DSLAM.

      This was going on long before fiber became as popular as it is now. New DSLAMs are likely to be fiber feeds, but the existing base is copper for historical reasons. If a technology allows higher data density over copper, then the upgrade to the provider is simply to fork lift out the old DSLAM and replace it with a more capable unit. No need to run fiber to get the new capability.

      That rate over that distance has been in the labs for quite a while. The issue is not the difficulty with the data rate over the distance, the difficulty is doing that without interfering with adjacent pairs in the cable. Receiver sensitivity and noise margin/rejection has apparently solved that problem.

      With some of the new wireless technologies coming on in the next two to three years, wired/fibered broadband for anything slower than 3Mbps is going to go the way of the dinosaur in any case.

      And 3Mbps addresses most of the user base for data access. Particularly in rural areas where there might be 1000 ft between houses, high speed wireless makes a lot more sense from both capex and opex.

    5. Re:Remote DSLAMs by Anonymous+Struct · · Score: 2, Funny

      It'll bring a whole new meaning to the term 'next hop'

    6. Re:Remote DSLAMs by tjstork · · Score: 3, Interesting

      A friend of mine did do a fiber to the curb sales pilot in Texas for quite a well that could give insane bandwidths. In fact I think Verizon ran a DSL fiber to the curb trial in Arizona where you could get 50+ Mbs up and down.

      --
      This is my sig.
    7. Re:Remote DSLAMs by mcrbids · · Score: 2, Interesting

      This has always struck me as stupid.

      Just be careful when you use strong language that you can take what you dish out.

      How long will it be, now that data outweighs POTS, until we get fiber to the front door?

      A few years ago, when I had not yet "made it", I saved a few hundred dollars by wiring my house's telephone lines with phone parts from the local dollar store, using a kitchen knife and a penny. (as a screwdriver)

      This wiring works very well today - I have 2 phone lines in my house, and a DSL modem that gives me 1.5 Mb throughput. The DSL modem has been tested to 6 Mb with no difficulty. (Since I went for the cheaper plan, my speed is capped)

      Tell me again why fiber is so much better?

      --
      I have no problem with your religion until you decide it's reason to deprive others of the truth.
  2. As rugged as they claim? by garcia · · Score: 4, Interesting

    When they talk about the extender DSLAM hardware being rugged they aren't kidding:

    Only the size of a small shoe-box, and being fully submersible to a depth of 5m (16 feet), the R8as can be deployed in more locations than any other DSLAM. It can be installed on a pole, or in a pit or manhole susceptible to flooding, as well as other locations such as un-powered cross-connect cabinets. Its small size and light weight also allows it to be suspended from overhead cable.

    I'd like to know if they were serving DSL through a submersed DSLAM during the testing phase. I'd really like to know if works as well as they claim.

    1. Re:As rugged as they claim? by grumling · · Score: 3, Funny
      I'd like to know if they were serving DSL through a submersed DSLAM during the testing phase. I'd really like to know if works as well as they claim.

      Well, if the gaskets hold up, it may even work better, since it will be water cooled.

      --
      "Well, good luck finding a judge that doesn't run a bestiality site."
    2. Re:As rugged as they claim? by dsginter · · Score: 2, Funny

      I'd like to know if they were serving DSL through a submersed DSLAM during the testing phase.

      Why? Do you have a submarine in need of broadband connectivity or something? ;)

      --
      More
  3. Australian Broadband... by Macfox · · Score: 4, Informative

    A few facts

    Oz Broadband is anything over 128kbs.(ISDN) Laughable yes.

    The maximum speed Tel$tra offer (over ADSL) is 1500/256kbs. *

    Up till this announcement, if you were over ~3.5km from the exchange, then you probably couldn't get ADSL.

    Telstra (Bigpond) charge for data usage in both directions and their largest offering is 10GB, with modem speed shaping there after.

    Telstra also force voice bundling. If you want ADSL, you must have voice and pay a minimum of $18.50AUD per month, even if you don't need it.*

    This new offering is best described as a mini DSLAM with a ~2.3Mbit backhaul. So even two users could potentially max it out.

    While it's good news for some that are out of reach. The overall state of Oz broadband isn't worth writing home about.

    * Some providers offer connection without a voice service (ULL) and ADSL2+ (24Mbs) but only in 5% of exchanges.

    --
    Area51 - We are watching...
    1. Re:Australian Broadband... by EasyComputer · · Score: 4, Insightful

      Yea, but thats the point, its for people who are already out of reach, not for those of us who have fast connections already.

      It seems that most people determine the value of new technology only according to how it benefits them, something can be beneficial to a few thousand people, but if it doesnt help us we think its nothing big. Actually this goes for everything, "Oh, they cured cancer? But I don't have cancer, therefore its a waste of time and money and is completely useless", Yea thats a bit overboard but it captures the mentality, I think.

      Ok I'm done, I'll post again in another few months.

  4. HENRICO COUNTY BROADBAND by 0110011001110101 · · Score: 4, Funny
    I hear henrico county is giving away 4 year old "gently used" broadband for only $50 lifetime membership!!

    Come quick, theres only 1,000 memberships left, and, oh yeah, bring a folding chair,waterproof pants, extra stroller, and riot gear if possible, it's gonna be one hellava fight, but a good beat down is always worth free crap right?

    --
    Don't anthropomorphize computers: they hate that.
  5. In Tokyo.... by djfray · · Score: 4, Funny

    Thanks to Telstra's latest creation, citizens within a twenty mile radius were alerted to Godzilla's rampaging battle with the creature of the same name.

    --
    This sig is o Unfunny o Funny
  6. Interesting, but... by suitepotato · · Score: 5, Interesting

    ...it isn't much beyond an incremental sort of gee-whiz improvement. You can send T1s over long distances and then break them out fractionally or hook them to a DSLAM and use as a backhaul for the customers. The submersion thing might have come about from submersible communications at sea or from the fact that many remote mechanisms in telecom tend to be underground and the waterproofing for those vaults tends not to be the greatest.

    I give it a big shrug and a I'll check into it later. I work in telecom so it does get my notice. Now if they make a 1.5Mbps line work to twenty miles on pure copper all the way, that will knock my socks off.

    --
    If my grammar and spelling are off, I am [distracted/tired/careless] (take your pick)
    1. Re:Interesting, but... by rugger · · Score: 2, Insightful

      Its not a huge technical acheivement, but an important one in spreading broadband across sparely populated suburbs and towns.

      The important thing with this is that carriers can install them basicly anywhere, on a pit, on a pole, anywhere conventional DSLAMs simply cannot be put. Another important thing is that it uses standard copper for the uplink, so rollout is inexpensive.

  7. Re:Oliver by RobertB-DC · · Score: 3, Interesting

    Please sir, may I have some broadband?
    rural new mexico


    You don't have to be very rural to wish for broadband. The nearest broadband of any sort is 10 miles away, even though I'm less than a half hour from Dallas.

    I started to wonder why this development was happening in Australia instead of here... then I remembered that 1) Australia has even more empty space than we do and 2) US telcos are a bunch of greedy bastards, and the limited rural market won't add enough to the bottom line.

    --
    Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
  8. always a trial by ch-chuck · · Score: 2, Interesting

    As a Verizon customer all during the DSL revolution, neither the house I had nor the apartments I'm in now are dsl'able. Both are within 2 miles of a CO but for some reason they don't offer it. I'd sure like to sign up for more reliable / commercial level (run my own web / email / streaming audio / etc ) than what I have with consumer cable, which costs $70 / month, incl. tv which I rarely watch.

    --
    try { do() || do_not(); } catch (JediException err) { yoda(err); }
  9. Re:there is a reason for this by pixelpusher220 · · Score: 2, Insightful

    Dude....call your local gov't and complain. it works.

    Here in Fairfax, VA, when the local cable (Media General) wanted to increase rates...the local gov looked at the massive stack of complaints and said...um..sure, right after you solve all these other problems for your current promised service.

    So make sure you aren't just whining on /. do it someplace that actually makes a difference ;-)


    --
    People in cars cause accidents....accidents in cars cause people :-D
  10. Greedy is global by noisymime · · Score: 3, Informative

    ohh don't worry, Australian Telcos (Especially Telstra) are greedy bastards as well. Its just that they're being strongarmed by the government to provide reasonable service to remote areas. Its a shame they're not being forced to do it at prices that are inline with the rest of the world.

  11. Perhaps too late to be important by Mostly+a+lurker · · Score: 3, Interesting

    If this technology had been available even five years ago, it would have been widely used. Now, I question whether it is going to be an economic solution. Recent advances in wireless technologies seem to promise a cheaper service in remote areas while being able to provide similar bandwidth.

  12. Re:Oliver by RobertB-DC · · Score: 2, Informative

    There's no southern sky for 10 miles?
    "of any sort" might not be the phrase you're looking for.


    You're right... let's call it, "any sort less than less than $50 a month" (alternate link here).

    --
    Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
  13. I was impressed by dfn5 · · Score: 3, Funny
    Until I converted to miles.

    --
    -- Thou hast strayed far from the path of the Avatar.
  14. Re:More info? by arrow · · Score: 3, Informative

    What this amounts to is moving the DSLAM from the central office to the pole outside your house, then wiring one or more T1/E1 lines to it.

    No magic "sprinkle this on your phone line and wait 10 minutes" here.

    There is nothing stopping you from deploying "this technology" for yourself today. Except maybe sticker shock. You'll shell out $500+/mo for the T1 line (since you don't already own the lines, like the Telco does), a couple grand for a DSLAM, and ~$100/mo in fees for dry pairs (assuming they even let you order them anymore) to your neghbors houses if you want to be nice and share.

    --
    symetrix. We are building a religion, a limited edition.
  15. Re:there is a reason for this by John+Seminal · · Score: 2, Informative
    Dude....call your local gov't and complain. it works.

    Here in Fairfax, VA, when the local cable (Media General) wanted to increase rates...the local gov looked at the massive stack of complaints and said...um..sure, right after you solve all these other problems for your current promised service.

    So make sure you aren't just whining on /. do it someplace that actually makes a difference ;-)

    Who do you complain to? Local city hall? What can they do? I thought only the FCC can do anything?

    I can give you a list of crap comcast has done that stinks.

    They keep raising fee's. Just looking at a bill, I can't tell what is a government tax and what is a comcast fee. Just a few months ago they raised the cost for basic cable. Then two months later, they removed Sci-Fi from the lineup. I called and comcast said that Sci-Fi was now only available with their digital package, but that costs more. I said "Since I was paying $80 a month for all these channels, and you took one away, how much will you lower my bill?". I got a laugh at the other end of the phone. Comcast said I was paying for a service, not any specific channels.

    And I swear, the picture quality is worse than just last year. Every now and then, when I am watching a baseball game, the screen will freeze and little boxes will form all over the screen. Once this happens, it takes them an hour to fix the problem, but that does nothing for me because I can't watch the game. And on the lower channels I get small little squiggly lines that just barely distort the picture. The only way I can describe it is if one line of the picture was a string, that someone was making a wave with the string. I went to a second TV just to double check, and the same problem was there too. It is barely noticable, like on a flat screen monitor the 2 little strings. But once you see them, you see them.

    And the damn cable modem is crap too. I mentioned it goes out at least twice a month, often for more than a couple of hours. But it will also re-set itself, at random. When it re-sets itself, it takes about 5 minutes for the internet connection to come back again. Pretty much what happens is all the lights on the cable modem are on, then it shuts off, then it blinks for five minutes. I called comcast, and they said that is normal. It sucks if I am in the middle of a download or if I was posting, and I get cut off.

    And for about 3 months last winter, I had no DNS service. If I wanted to visit a website, I had to know the IP address and enter it as numerals. Someone here at slashdot told me to change the DNS myself, and I used verizon for a month. I felt like a thief.

    And every time I call comcast, it is the same thing. I speak with someone who knows less about computers than your avarage 14 year old. They are often rude. They often want to put you on hold, for long amounts of time. And they end the call before the problem was fixed.

    --

    Rosco: "If brains were gunpowder, Enos couldn't blow his nose."

  16. *ahem* "Ruggedized" by IorDMUX · · Score: 3, Funny

    I've been seeing this word quite often in datasheets of chips we use in the lab. (Like here, in the Description.) My first impression was a small, black IC with a confederate flag painted on top... perhaps some unnecessary facial hair, as well.

    Now, the word 'rugged' comes from the Scadanavian word for 'shaggy'. However, the popular cowboy mentality has managed to transform 'unkempt' into 'robust', as evidenced by the definition for 'ruggedize':
    --to strengthen (as a machine) for better resistance to wear, stress, and abuse--

    I'm going to assume, then, that my chip contains a powerful Texan spirit that herds the current like the stampeding mass of electrons that it is.

    --
    >> Standing on head makes smile of frown, but rest of face also upside down.
  17. Completely misleading press release by mike_lynn · · Score: 3, Insightful

    If you read the wording of the press release, it says that people can get access to DSL "up to 20KM from a central exchange". Key words: central exchange.

    When most people in the US run into a distance limit, it's the 5200m/~3 mile distance from *the nearest DSLAM*, not the central exchange. So when people read this press release, they think: "Wow, now DSL goes 15km farther!"

    This is an unspoken lie. The Wikipedia entry their own press release links to lists a distance limit of 3km to the premises and further digging turns up G.SHDSL can be deployed up to about 12km from the central exchange ... or nearest fiber tie-in.

    Grand total: 15km.

    *Apparent* improvement: 10km ... but people forget that their local DSLAMs are already some considerable distance away from their own central offices.

    Working for an ISP has its advantages ... I just ran a distance check between a remote I know of and the central office it's deployed out of: 11km.

    So total distance from central office where I am that people can get DSL: Around 16km

    Distance Telstra should be getting using the technology they're talking about: 15km / roughly the same.

    Distance Telstra claims: 20km

    I don't know where that last 5km is coming from, but I bet it's because in this 'longest run' they've got fiber in there somewhere. If fiber isn't being used, I would _really_ like to see some specs on the data rate they get out of that 20km run.

    The only advantage to this technology is that it can be deployed using an unused copper pair, which is already installed everywhere that anyone would want DSL.

    1. Re:Completely misleading press release by jabuzz · · Score: 2, Interesting

      This 3km limit is a load of cobbliers. The vast majority of lines will work just fine out to 7-8km, and some much further.

      Last year BT did a large in the field trial of "extended reach" ADSL. Basically they hooked any line, no matter what the distance to the DSLAM and let the customer hook up their modem and saw what happened.

      In most cases it just worked, and in the cases where it did not work, a visit from an engineer to fit a ADSL filter at the NTE5 (the master socket in the house) and the vast majority started working. In the UK the official estimate from BT is that about 0.2% of all telephone lines will not work with a 512kbps ADSL connection.

      The result of the trial is that if you order a 512kbps ADSL line they hook you up regardless. If it does not work you get an engineer visit, and if you are in the unlucky 0.2% you get a refund.

      Any ADSL provider enforcing distance limits needs their head examining. The biggest problem by far with long lines not working is the mess of extensions in the house. Solution filter the ADSL signal off at the master socket. What could be simpler.

      See the following URL's for more information.

      http://www.samknows.com/broadband/news.php?id=201
      http://www.adslguide.org.uk/newsarchive.asp?item=1 814

  18. Shoddy Cable Plant by PhraudulentOne · · Score: 2, Interesting

    It sounds like Telstras cable plant is pretty shoddy. We have remote DSLAMS near the customers so that we can give them great speeds. Soon, we will be putting a bunch more in so that everyone can get ADSL2+. This crap that Telstra is using sounds like a massive cop-out. It's not going to last very long if you have 2+ (max 8!) users sharing 2.3MBit. You also have to remember, these are people that have been ITCHING to get highspeed because it has been unavailable for so long. When they get it, they will be using it a lot, which means it will suck for those sharing 2.3MBit with 8 people. Telstra should get their act together and start laying fibre. Then they can put REAL DSLAMs near each neighbourhood and do 8MBit with ADSL, or greater speeds with newer technologies. 2.3Mbit won't be highspeed for much longer.

    --
    You create your own reality - Leave mine to me.