30km ADSL ?

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gerasmus

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Can anyone give me more information about ADSL technology that can apparently extend the ability to increase an exchange's ADSL connections from the current maximum of 5km to 30km ?

A Telkom phone techie recently told me about this and that this would be enabled in our local exchange (Ellisras) in the next few months.
If true this would be a heaven sent for people like me living on a farm just outside the current maximum's reach.
 
Serious doubt this tale you have been spun. Even if they role out ADSL2+, the distance from the exchange will be a stretch at 6km.

internode-adsl2-dist07.jpg
 
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moggie said:
Serious doubt this tale you have been spun. Even if they role out ADSL2+, the distance from the exchange will be a stretch at 6km.

internode-adsl2-dist07.jpg
Click to expand...

i agree there is no way it can go to 30km, 6km would be the max
 
Down here in sedgefield (that's on the garden route, for those who don't know :)) telkom installed a mini dslam for a single adsl applicant who lived 10km outside of town, and about 12 km (as the crow flies - line length is probably greater) from the town's exchange. Then she moved. The dslam stayed. It's over beyond pine lake marina by trails end if anyone is interested...
 
Had to recheck my networking facts before posting:

Distance from DSLAM and max speed:

* 25 Mbit/s at 1,000 feet (~300 m)
* 24 Mbit/s at 2,000 feet (~600 m)
* 23 Mbit/s at 3,000 feet (~900 m)
* 22 Mbit/s at 4,000 feet (~1.2 km)
* 21 Mbit/s at 5,000 feet (~1.5 km or ~.95 miles)
* 19 Mbit/s at 6,000 feet (~1.8 km or ~1.14 miles)
* 16 Mbit/s at 7,000 feet (~2.1 km or ~1.33 miles)
* 1.5 Mbit/s at 15,000 feet (4.5 km or ~2.8 miles)
* 800 kbit/s at 17,000 feet (~5.2 km or ~3.2 miles)
 
Grouter said:
.... telkom installed a mini dslam for a single adsl applicant who lived 10km outside of town, and about 12 km (as the crow flies - line length is probably greater) from the town's exchange.
Click to expand...

What is a DSLAM ? Is that something like a relay station from the main exchange ? If so, then this is what's been installed in the town wherte I live because the town is split in two with about 3km of nothing in between the two parts (and only one heavily congested road inbetween). The exchange was in one part of town. By putting the repeater/relay (whatever it's called) probably enabled the rest of town to also get ADSL.

Telkom techie told me we had very bad quality copper, even though we are only 1,3km from where I think the repeater is located. When I pick up phone I can hear a lot of line noise or something that sounds like static from the Telkom line. And they never bother to fix it. Telkom techie told me that becoz of this low copper quality, even though I am close to the relay, I may not be able to get ADSL.
Can this be true ? Any1 had similair experiences ?
 
One possibility is the introduction of repeaters that extend the distance. Very possible to extend the length to 30km but you will have many repeaters and poor latency.
 
Sounds like your dorp has a mini dslam, yes. Probably what the tech means by a 'relay'. We have a couple scattered 'round the town.

As regards the line, I would kick up a stink. It belongs to telkom, but you pay them rental for it. Even on a "best effort" service, a noisy line is unacceptable. Demand they fix it, simple as that. Then you might get dsl.
 
DSLAM: DSL access multiplexer

Aggregates multiple DSL subscriber lines and connects them to a larger carrier or to the Internet backbone.

(Network+ Guide to Networks, 4th Edition, Tamara Dean)
 
Grouter said:
Sounds like your dorp has a mini dslam, yes. Probably what the tech means by a 'relay'. We have a couple scattered 'round the town.

As regards the line, I would kick up a stink. It belongs to telkom, but you pay them rental for it. Even on a "best effort" service, a noisy line is unacceptable. Demand they fix it, simple as that. Then you might get dsl.
Click to expand...

Its common for even a hotel or security complexes to have their own DSLAM. Its not big equipment.

The DSLAM in turn is connected to ATM (Asynchronous Transfer Mode) circuits.

You can pick up ADSL2+ mini-DSLAMs for about R7k. (edit, you can get for even R2K, so the hardware is not expensive).
 
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En dit is F*%ken warm plek hier ! Plattelandse dorp ! Telkom telkom. I should've bought shares on their IPO !

I think you are right because a few years ago my bro was told that our shop was just-just within ADSL range. But then when I asked Telkom techie a recently he said that our shop can now get 4mb easily. Telkom must've then installed a DSLAM. Doesn't help me though because I can't make my bed in the shop :( In our dorp, everything happens at 1/4 of Africa speed. And I am sure you know what Africa speed is.
 
cbrunsdonza said:
Its common for even a hotel or security complexes to have their own DSLAM. Its not big equipment.

fibre
Click to expand...

incedently, our shop is a 113 room hotel with private PABX system installed by Northern Telekom from Pietersburg (nowadayz known as Polokwane).
I dunno about any fibre running to the hotel. The owner has a techno phobia.
 
Guess it all depends on how big the complex is and your needs. A R2K min-DSLAM is sufficient for even 8 users.

iBurst for one are installing DSLAMs (various sizes) in security complexes.
 
gerasmus said:
I think you are right because a few years ago my bro was told that our shop was just-just within ADSL range.
Click to expand...

That would be from the DSLAM at the exchange. Without it there would have been no ADSL services in your dorpie.


gerasmus said:
Telkom must've then installed a DSLAM. Doesn't help me though because I can't make my bed in the shop :( In our dorp, everything happens at 1/4 of Africa speed. And I am sure you know what Africa speed is.
Click to expand...

Probably installed a UMC.

I would love to have ADSL in a small dorpie. There should be zero contention issues and your link should be super-quick. That is, of course, if you live close enough to the exchange or UMC.
 
moggie said:
I would love to have ADSL in a small dorpie. There should be zero contention issues and your link should be super-quick. That is, of course, if you live close enough to the exchange or UMC.
Click to expand...

You are 100% correct there. 250 m from our beloved little tin shack, sorry, exchange.

I've used friends and relatives uber-fast lines in Australia and UK and what do you know? My piddling 384 line holds it's own to be honest. Just anecdotal, no stats to prove it, but it made me realise that just because you see 10 Mb/s on the router doesn't guarantee you perfect, lightning speed internet
 
moggie said:
That would be from the DSLAM at the exchange. Without it there would have been no ADSL services in your dorpie.




Probably installed a UMC.

I would love to have ADSL in a small dorpie. There should be zero contention issues and your link should be super-quick. That is, of course, if you live close enough to the exchange or UMC.
Click to expand...

Sorry, what is a UMC?

My networking is rather virgin, and cannot remember coming across this in my studies last year.
 
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