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1mb: Line length or SNR/ATT, which is more important to BT?

 
 
broughcut@gmail.com
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      06-03-2005, 05:51 PM
Hi,

Do BT's presumptions about line length take precedence over the actual
results when it comes to getting an upgrade? Can I request that the ISP
submits the request manually, and that BT send out an engineer to do a
calibrated line test if they aren't prepared to give it a try on the
basis of the ISP's remote woosh test?

ISP wooshed my equipment yesterday and the line appears to be within
limits for a 1mb service, 25db SNR / 60db ATT.

I am now informed that the upgrade has fallen at the first hurdle, BT's
online ordering system -- apparently, there is now 'no way' my line can
support anything above 512K, but the ISP went on to remark that this is
not due to line loss, simply that the actual distance from the exchange
is too great, which doesn't really make any sense.

At this point, I was referred to BT's online availability checker to
'confirm' the regrade could not be placed (thanks to BT's more relaxed
policies for 512K, the same availability checker didn't hamper my
activation, even though it all but rules out ADSL in any shape or form
on my 'very long line' -- so why should it factor here?).

Has to be said I'm delighted with the service I'm getting, from the
512 ADSL connection and the ISP generally, but I still want to try for
1mb, I can always go back to 512 if it has problems.

 
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Phil Thompson
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      06-03-2005, 06:38 PM
On 3 Jun 2005 10:51:52 -0700, (E-Mail Removed) wrote:

>Do BT's presumptions about line length take precedence over the actual
>results when it comes to getting an upgrade?


their presumptions about line loss drive the number checker and that
plays a key role in the automatic ordering systems. You can't place an
automatic order for a service the checker says isn't available.

>Can I request that the ISP
>submits the request manually, and that BT send out an engineer to do a
>calibrated line test if they aren't prepared to give it a try on the
>basis of the ISP's remote woosh test?


you can ask the ISP to do a manual order using the stats as supporting
evidence. Some will, some won't. Not all will succeed. You won't get
an engineer out to test the line.

>ISP wooshed my equipment yesterday and the line appears to be within
>limits for a 1mb service, 25db SNR / 60db ATT.


I believe the limit is <60 dB so that's out of limits :-(

>I am now informed that the upgrade has fallen at the first hurdle, BT's
>online ordering system -- apparently, there is now 'no way' my line can
>support anything above 512K, but the ISP went on to remark that this is
>not due to line loss, simply that the actual distance from the exchange
>is too great, which doesn't really make any sense.


most ISP drivel in this area doesn't make sense, they are trying to
express it in terms they think you wil understand while not
understanding it themselves.

>At this point, I was referred to BT's online availability checker to
>'confirm' the regrade could not be placed (thanks to BT's more relaxed
>policies for 512K, the same availability checker didn't hamper my
>activation, even though it all but rules out ADSL in any shape or form
>on my 'very long line' -- so why should it factor here?).


because for 512 or 256k the regime is to try it and see if it works
and let you decide if you want to keep it. This isn't the regime for
1M which has a <60 dB limit.

http://www.farina1.com/bookmark/0000...7/00020260.HTM

Phil
--
Tiscali - dialup speeds at Broadband prices, see
http://bbs.adslguide.org.uk/postlist...&Board=tiscali

AOL - the unlimited ISP of choice for heavy downloaders.
 
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kraftee
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      06-03-2005, 06:58 PM
(E-Mail Removed) wrote:
> Hi,
>
> Do BT's presumptions about line length take precedence over the actual
> results when it comes to getting an upgrade? Can I request that the
> ISP submits the request manually, and that BT send out an engineer to
> do a calibrated line test if they aren't prepared to give it a try on
> the basis of the ISP's remote woosh test?
>
> ISP wooshed my equipment yesterday and the line appears to be within
> limits for a 1mb service, 25db SNR / 60db ATT.


60db is the limit for 1Mb which is probably why your order failed.....


 
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broughcut@gmail.com
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      06-03-2005, 07:21 PM
I thought the limit was equal to or less than 60db. From what you're
saying it sounds like BT will ultimately reject it, but PN copied me on
the woosh result which was 60db, and on this basis advised it may not
be a perfect connection (not that it was out of limits), before
attempting to place the order with BT. So, at the moment it's only been
rejected on 'length', not attentuation. I asked them to put it in
manually so will see what happens, although I can probably guess....

 
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kraftee
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      06-03-2005, 08:01 PM
(E-Mail Removed) wrote:
> I thought the limit was equal to or less than 60db. From what you're
> saying it sounds like BT will ultimately reject it, but PN copied me
> on the woosh result which was 60db, and on this basis advised it may
> not be a perfect connection (not that it was out of limits), before
> attempting to place the order with BT. So, at the moment it's only
> been rejected on 'length', not attentuation. I asked them to put it in
> manually so will see what happens, although I can probably guess....


Well you won't be any worse than the miriad of people who are getting
upgraded without any testing (& sometimes without their knowledge) & then
find that their service does not work at all. If this happens to you at
least you'll have a big clue as to what's gone wrong

It's got that bad that field staff are (at the present moment) being told
not to visit & to refer back to the ISP's so that the line can be regraded
to a service level the line will support.....I kid you not....

We'll see how long that one last ;-)


 
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Phil Thompson
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      06-03-2005, 09:27 PM
On 3 Jun 2005 12:21:49 -0700, (E-Mail Removed) wrote:

>I thought the limit was equal to or less than 60db.


pass. Plusnet say "You need a line loss of less than 60 dB" etc etc.
BT press release said "The new line loss limit for 1Mb/sec ADSL will
be 60dB" which isn't specific.

Either way, if the checker says 512k only then its a manual order to
get anywhere from here.

Phil
--
Tiscali - dialup speeds at Broadband prices, see
http://bbs.adslguide.org.uk/postlist...&Board=tiscali

AOL - the unlimited ISP of choice for heavy downloaders.
 
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Gareth
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      06-03-2005, 09:57 PM

"kraftee" <kraftee@spamoff&die> wrote in message
news:42a0b726$0$3882$(E-Mail Removed)...
> (E-Mail Removed) wrote:
>> I thought the limit was equal to or less than 60db. From what you're
>> saying it sounds like BT will ultimately reject it, but PN copied me
>> on the woosh result which was 60db, and on this basis advised it may
>> not be a perfect connection (not that it was out of limits), before
>> attempting to place the order with BT. So, at the moment it's only
>> been rejected on 'length', not attentuation. I asked them to put it in
>> manually so will see what happens, although I can probably guess....

>
> Well you won't be any worse than the miriad of people who are getting
> upgraded without any testing (& sometimes without their knowledge) & then
> find that their service does not work at all. If this happens to you at
> least you'll have a big clue as to what's gone wrong
>
> It's got that bad that field staff are (at the present moment) being told
> not to visit & to refer back to the ISP's so that the line can be regraded
> to a service level the line will support.....I kid you not....
>
> We'll see how long that one last ;-)


It's disgraceful.

I'm using a shorting copper pair that can still astonishingly provide a 1Mb
service with a degree of reliability when all my neighbours are enjoying an
automatic upgrade to 2Mb and a promise of more.

Instead of digging up the faulty cable a 2nd opinion BT engineer found a
spare pair entering the home and used that instead. The obvious point, that
it was part of the same faulty cable, was lost on him but not on the 1st
opinion engineer who explained that there may well be another pair entering
the home but as the cable itself was physically damaged there was no point
looking for it/connecting it. Well, he was wrong because whilst the
currently used pair can support a 1Mb connection from anywhere between 8
hours to 294 hours it can't support a connection for any longer than that
and it can't support a > 1Mb service at all. My outside wall linebox has the
ground feed wire cut back and black masking tape wrapped around it to aid
insulation!

Of course I don't expect BT to spend thousands of pounds to provide me with
anything more than a basic voice and data service but I think the tendency
not to invest in correcting clearly faulty infrastructure is a pretty shit
policy for the end user - the only alternative I have is NTL and I'm not
even going to seriously consider that option.

Gareth.



 
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broughcut@gmail.com
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      06-04-2005, 08:56 PM
odd... router was plugged into the front of the ADSL faceplate on the
main BT box via an rj11. Moved the router this evening with a 7 mt
cat5 cable run to an adsl extension box and hard wired the cable into
the back of the main faceplate with the idc tool -- I was half
expecting a slight drop but the attenuation improved by 1.5db, now
58.5db. Could be external factors or a dodgy rj11/45 port on the
faceplate... now on the sunny side of the street so far as attenuation
goes anyway.

 
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Reg Edwards
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      06-05-2005, 10:29 AM
There are millions of local phone lines all of different
characteristics. Sensibly all of them belong to BT. Odds and sods of
Internet Providers merely rent use of their lines from BT, but
occupying the cream and most profitable sectors of the market.

You cannot expect BT to conduct time-consuming and expensive tests on
everybody's line who has a query about the possibility or quality of a
service. As likely as not the problems lie in the non-BT transmission
equipment rather than in the lines themselves. The lines, perfectly
adequate for ordinary phone service, cannot be replaced except by
optical fibres. That will take 20 years. It has taken 100 years to
develop the phone system to its present state. And, to everybody's
front door, how will it be paid for?

To everybody without a satisfactory Internet service, or wondering
when they will obtain one, there is no alternative but to be patient.
Or to sell your house and move nearer to a more favoured telephone
exchange. And then hope it doesn't become over-saturated with
traffic.

Equipment for reliable radio links to remote areas will be available
only to the very rich - circumstances which have prevailed in the
Internet provider's market since its inception.
----
From a retired GPO and BT engineer.


 
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mr_flibble
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      06-05-2005, 12:13 PM

(E-Mail Removed) Wrote:
> odd... router was plugged into the front of the ADSL faceplate on the
> main BT box via an rj11. Moved the router this evening with a 7 mt
> cat5 cable run to an adsl extension box and hard wired the cable into
> the back of the main faceplate with the idc tool -- I was half
> expecting a slight drop but the attenuation improved by 1.5db, now
> 58.5db. Could be external factors or a dodgy rj11/45 port on the
> faceplate... now on the sunny side of the street so far as attenuation
> goes anyway.


Good luck.

I was on a 1mbit connection with an attenuation of 64db (measured by
bt engineer), so all is not lost, your stats actually look better tha
mine did so you should be able to hold a 1mbit connection. M
connection was rock solid.

Keep on plugging away at your isp and let us know how you get on

--
mr_flibble
 
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