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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.""
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;
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.
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...
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.
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
...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)
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.
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.
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.
-- Thou hast strayed far from the path of the Avatar.
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.
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.
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.
... or nearest fiber tie-in.
... but people forget that their local DSLAMs are already some considerable distance away from their own central offices.
... I just ran a distance check between a remote I know of and the central office it's deployed out of: 11km.
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
Grand total: 15km.
*Apparent* improvement: 10km
Working for an ISP has its advantages
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.