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[Black Sheep]

As I'm waiting around to be taken to the boozer by my missus, I thought I'd do a quick WHOOSH test against my own VDSL circuit.

My DS is 65.7Meg, and my US is 19Meg. My service profile is ... 40M-80M Downstream, Interleaving Low - 10M-20M Upstream, Interleaving Off and has only changed the once, from its initial 128Kbps-80Mbps profile on start-up of the product. I was getting the full 80/20 Meg speeds on start-up.

I was the 2nd EU to go 'Live' on my Cabinet, my circuit is 0.5mm Copper all the way from the PCP, and believe me when I say it tests as good as any line could wish to be. There are now 36 EU's with VDSL service on this PCP

So, I can only deduce that 'Crosstalk' is alive and well, and is the culprit behind my 15Meg deficit ?? I thought it worth mentioning as quite a few contributors don't believe that Xtalk is as big an issue as it is, and think engineers 'use it' as an excuse to fob them off with. Roll on vectoring, eh ??   

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Edited by Admin
(added crosstalk to topic title)

[kitz]

15Mb seems an awful lot to lose for crosstalk.  Im pretty  sure BE would agree with this statement.

Im still connecting at 80/20, but have noticed my max attainable that at first was @ 103.5Mb is now 88.5Mb
Upstream was circa 35.5Mb and is now 30Mb.   So thats a 'loss' of 15Mb for me too.

[Bald_Eagle1]

For some of us, who have an obsessive curiosity, it would be interesting to know just how low your connection's DS Interleaving depth is as mentioned here:-

"40M-80M Downstream, Interleaving Low - 10M-20M Upstream, Interleaving Off"

I am guessing that at a speed of 65.7Meg you probably haven't noticed much in the way of a deteriorated service?

 

If you recall, after my connection issues were finally fixed, I was able to achieve sync speeds of around 30 Mbps for quite a few months before it gradually started to decline to its current 20 Mbps.

This decline was put down to crosstalk as all physical line tests resulted in LTOK.
Crosstalk as more users have been connected is quite possibly the real reason as I did see a stepped deterioration starting early January 2013.


I can actually see/feel this deterioration, especially when working from home over a VPN connection to my employer's server(s) & my general internet 'experience' has also deteriorated.


At the time I eventually reported the speed decline (late April/early May), my DS speed estimate was still 30 Mbps.
i.e. my sustained sync speed was more than 25% below estimated speed, which warranted a number of engineer visits to investigate.


Apparently, my cabinet in now almost 'full', therefore various visiting engineers assumed the deterioration must be due to increased crosstalk.


Within a few days of reporting the speed deterioration, the response was to lower my DS speed estimate to 22 Mbps, therefore my connection is supposedly now performing "within acceptable limits".

I did think that was a bit of a 'cop out' as there was no conclusive evidence that crosstalk had indeed caused the decline.



Now then, I notice the format of the BT BROADBAND AVAILABILITY CHECKER has changed this morning:-

https://www.dslchecker.bt.com/

It now shows estimates for FTTC Range A (Clean) & FTTC Range B (Impacted).

Unfortunately, there is no explanation of what 'Impacted' means.

Do you know if 'Impacted' is some sort of reference to connections impacted by crosstalk (or something else)?

For my connection, the estimated speeds are actually the same for Clean & Impacted.


See the attached screenshots, firstlky for my estimates before today &  secondly today's estimates.

[ryant704]

If you check now BE they have added

"For FTTC Ranges A and B, the term "Clean" relates to a line which is free from any wiring issues (e.g. Bridge Taps) and/or Copper line conditions, and the term "Impacted" relates to a line which may have wiring issues (e.g. Bridge Taps) and/or Copper line conditions."

This new revised estimates were added last night at some point as I checked around 6pm last night.

Just to point out both my speeds are the same as well.

[NewtronStar]

I have a question for BE1, before the decline of thoughput speeds did you notice anything untowards in your stats like big changes in SNRM's and also any high errors ?

[Bald_Eagle1]

If you check now BE they have added

"For FTTC Ranges A and B, the term "Clean" relates to a line which is free from any wiring issues (e.g. Bridge Taps) and/or Copper line conditions, and the term "Impacted" relates to a line which may have wiring issues (e.g. Bridge Taps) and/or Copper line conditions."

Which URL are you using?
It doesn't show that detail for my connection when using https://www.dslchecker.bt.com/

[ryant704]

http://www.dslchecker.bt.com/adsl/adslchecker.welcome

[Bald_Eagle1]

I have a question for BE1, before the decline of thoughput speeds did you notice anything untowards in your stats like big changes in SNRM's and also any high errors ?

See the attached (320 days of stats).

It's not just throughput speeds, it's actual sync speeds & attainable rates that hve deteriorated.

Due to the scale of the graphs over 320 days it's not all that clear, but I did see lowered SNRM for a few days before each lower speed resync.
The most noticeable was from 08:28, 31/12/2012, although the connection didn't resync at a lower speed until 01:18, 05/01/2013.

[Bald_Eagle1]

http://www.dslchecker.bt.com/adsl/adslchecker.welcome

Thanks for that link. It does now include the explanation for my connection.

[NewtronStar]

gonna look at your stats carefully 

I am having issues as you know and just did availability check and my Cab Number has changed  could this be my problem ?
see below.

edit never mind could of swore it said cabinet 4

[burakkucat]

[off topic]

If the End User wishes to migrate from their current Broadband supplier they will need to contact them in the first instance to obtain a MAC (Migrations Authorisation) Code, and then contact their new Broadband supplier to arrange for the service to be migrated.

I would have thought, given her age, that by now Beattie could construct a sensible sentence . . . 

If the End User wishes to migrate from their current Broadband supplier they will need to contact them in the first instance to obtain a MAC (Migrations Authorisation Code) and then contact their new Broadband supplier to arrange for the service to be migrated.

Big hints: Remove the redundant comma that follows the word "Code" and precedes the word "and". Move the closing parenthesis that follows the word "Authorisation" and precedes the word "Code" so that it follows the word "Code" and precedes the word "and".

 

[/off topic]

[NewtronStar]

[off topic]

I would have thought, given her age, that by now Beattie could construct a sensible sentence . . . 

I am stunned  how were you able to determine the Sex of Beattie

[kitz]

Whenever someone types "Beattie" I have an instant image of Beattie Bellman & not BT the teleco.

[NewtronStar]

Whenever someone types "Beattie" I have an instant image of Beattie Bellman & not BT the teleco.

Thats a Drag Queen for sure 

[burakkucat]

Whenever someone types "Beattie" I have an instant image of Beattie Bellman & not BT the teleco.

Some good memories here.    It's just unfortunate that all the links return a "404".