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ADSL Exchange and Line Checker Question

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ADSL Exchange and Line Checker Question

I've done a check for my new number for when we move to my parents' later this month and have a couple of questions:
It estimates a Fixed ADSL Line Speed to be 1024kbps and DSL Max to be 3000kbps.
1) I understand these are only estimated figures based on distance from the exchange (2.29km direct, 3.86km by road) but my mother has had a fixed 2M stable connection for almost 5 years initially with PN and now with Sky. Does this mean that when I take the new line and have Max enabled I could expect speeds to be substantially higher than the estimated 3000kbps?
2) It states that the exchange will be 21CN enabled on 30/3/09 which is good news as it's the day before my line/BB is due to be activated but there is no estimated speed. I checked a few other telephone numbers/post code combinations I know and, whether or not the exchange had been 21CN enabled, there was never an estimated speed shown. Any clue as to why this is?

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Re: ADSL Exchange and Line Checker Question

Mine says
Distance:-  Direct:    4.07 km
  (appx)* By Road: 4.99 km
and I have a stable sync of 3776kbps
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Re: ADSL Exchange and Line Checker Question

Is that with 21CN or ADSL Max?
That's not so bad.. really for Max. I just think I've been spoilt over the last three years with the exchange just yards away Smiley

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Re: ADSL Exchange and Line Checker Question

Max - my exchange isn't 21CN enabled and in any case I will see little or no improvement with an attenuation of 51dB
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Re: ADSL Exchange and Line Checker Question

I'll check what the attenuation is on my mother's line when I visit tomorrow.
Can I assume that the attenuation for my new line is going to be the same as the existing one or can there be great differences due to new cabling, etc? My parent's house was built 8 years ago.

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Re: ADSL Exchange and Line Checker Question

It will probably be similar as they won't run a new line - just pick up a spare pair in the nearest green box
Unless of course you get one that was rejected by another customer because of ADSL problems  Sad
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Re: ADSL Exchange and Line Checker Question

I'm a bit confused here, Jim - getting old Sad
The fella I spoke to when I ordered the new line informed me that, as I was having BB on it and my parent's already have BB on their line a new cable would have to be run into the house.
You answer seems to indicate that they would use the existing wiring?

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pierre_pierre
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Re: ADSL Exchange and Line Checker Question

I thought I was Old, the Green Box is that funny thing that sits by the side of the road and has lots of cable terminations in it Cool
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Re: ADSL Exchange and Line Checker Question

He would run a new cable into the house but only from the nearest point where there is a spare pair.
It might be the  pole where the other connection comes from or if there isn't one there the nearest green box to your house
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Re: ADSL Exchange and Line Checker Question

I assume 21CN technology is too new for meaningful estimates of speed capabilities on a particular line to be provided by BT.
Based on information from Kitz's checker, the attenuation for a 3.86km line is likely to be 50-55dB (Oldjim's line is either a good one or doesn't follow the road). Speed on maxDSL might reach 4000kbps, 4200kbps on 21CN. However the stepping of IP Profiles would give the same 3500kbps profile in both cases.
David
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Re: ADSL Exchange and Line Checker Question

Thanks for the replies.
I misunderstood what Jim said. A new cable will be pulled from the green box to my parents' house which is what I expected. When Jim said they won't run a new line I now assume he meant not from the exchange rather than from the green box.
If I can get around 4000kbps on ADSL2 then that's not as bad as a fixed 2M - hopefully it will be stable.

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Re: ADSL Exchange and Line Checker Question

Checked my parents' connection last night and they have Att of 49 with Noise Margin of 19. My current Att is 5 and NM is 12.5.
How would interleaving on or off affect the new line and would it remain stable?

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Re: ADSL Exchange and Line Checker Question

That actually is worrying  as it would tend to indicate a noisy line (default noise margin of 15dB)
Deleted - thanks "Fork Handles"  Grin I forgot about the fixed line.
Given the attenuation and with a fair wind you should get  over 4500kbps even with a 9dB noise margin
The new line will have interleaving enabled by default which is no problem unless you are into gaming. If you need low pings then it is just possible the default noise margin will rise to 12dB which will still give reasonable speeds.
All you can do is wait until you are connected then monitor the corrected errors. If they are low then taking off interleaving would be no problem. If they are high you may have to forgo speed for low pings
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Re: ADSL Exchange and Line Checker Question

Quote from: Mav
Checked my parents' connection last night and they have Att of 49 with Noise Margin of 19. My current Att is 5 and NM is 12.5.

Quote from: Oldjim
That actually is worrying  as it would tend to indicate a noisy line (default noise margin of 15dB)

But isn't that on the existing 2Mb fixed line?
Not young enough to know everything
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Re: ADSL Exchange and Line Checker Question

Quote from: Oldjim
That actually is worrying  as it would tend to indicate a noisy line (default noise margin of 15dB)

Perhaps the new line will be slightly better?
I don't do gaming so low pings are not that important. Pings on my current line tend to be in the low 40s - will have to wait and see what I will get.
Quote from: 4Candles
But isn't that on the existing 2Mb fixed line?

Yes - would the Att and noise Margin be different, then for MaxDSL? If so, I never knew that. I just assumed that a fixed line was, possibly, better and more stable because of those figues
Thanks for your help Smiley

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