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After my FTTC installation at work, we have the following attainable rates according to the openreach modem
Downstream 132728
Upstream 41166
Cable length is about 50 metres according to the openreach engineer.
Andrew
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You need to get Asbokid's instructions on how to access the modem and pull of the various details.
It should prove interesting reading for some!
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M H C
taurus excreta cerebrum vincit
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Hi, which commands would like you run?
I run the following:-
# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 40609 Kbps, Downstream rate = 132328 Kbps
Path: 0, Upstream rate = 10000 Kbps, Downstream rate = 39998 Kbps
Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 40609 kbps 132328 kbps
Actual Aggregate Tx Power: - 8.7 dBm 12.5 dBm
============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 2.3 7.9 10.3 N/A 4.3 9.3 14.1
Signal Attenuation(dB): 0.0 N/A 7.8 N/A 4.3 9.3 14.1
SNR Margin(dB): 31.0 N/A 31.0 N/A 31.2 31.2 31.8
TX Power(dBm): -23.8 -128.0 -10.0 N/A 9.8 6.7 5.5
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Register (or login) on our website and you will not see this ad.
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Very nice. 
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Have you got the tools to plot SNR against tones?
As you have a near perfect installation it would be good to see a plot of it to use as reference. Especially as my 17a max is about 63Mbps
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M H C
taurus excreta cerebrum vincit
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Managed to get the info for the graphs
http://www.andew.entadsl.com/line_stats.png
Andrew
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Hi andrew,
Managed to get the info for the graphs
http://www.andew.entadsl.com/line_stats.png
Andrew
I have been knocking together some Windows only batch files that auto login to a terminal program (Plink -related to, but not PuTTy), obtain the details from the 5 xdslcmd info commands:-
xdslcmd info --pbParams
xdslcmd info --linediag
xdslcmd info --bits
xdslcmd info --show
xdslcmd info --stats
& then generate these (& other) graphs.
I would be very interested in testing my batch files with data from good connections (unlike my own problematic connection - I have added a message to one of your brother's older threads from July as that is apparently a similar distance from the cabinet as mine), & would very much appreciate it if you could forward me either a PuTTy or a Plink log of the 5 commands mentioned above (for your good connection).
Please see my PM to you for my contact details.
Paul.
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How long is your D-side ? I see 75 - 77 prospective with my line, isn't it making very hard work of this all unless the attenuation is known ?
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And I thought mine was good with a 300 meter line.
BT Infinity
ROUTER:-Netgear WNDR37AV
JDSU Stats
Attainable 97040D 35659U
Sync 39999D 9995U
Attenuation: 9.6 SNR: 22.6
Line Length 300meters
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Hi Zarjaz,
How long is your D-side ? I see 75 - 77 prospective with my line, isn't it making very hard work of this all unless the attenuation is known ?
Do you have any ideas as to how an engineer's JDSU calculates an overall attenuation value?
Those who have access to an unlocked modem can see attenuation values, but they are split across the various 17a profile band plans:-
| Text | 1
23
45
| VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 8.3 52.8 64.1 N/A 21.6 63.0 0.1 Signal Attenuation(dB): 14.8 52.0 N/A N/A 21.6 63.0 N/A
SNR Margin(dB): 6.1 6.3 N/A N/A 3.8 3.7 N/A TX Power(dBm): -4.2 5.8 N/A N/A 10.9 6.6 N/A |
It would be really useful to know how the JDSU & modem reported values relate to each other.
Ideally, someone with access to both an unlocked modem AND a JDSU at the same time could post some comparative values, either here or via a PM?
A visiting BT engineer quite recently told me that my DS attenuation was around 22 dB, but that would appear to only match the downstream D1 band as shown above.
He also told me my D-side was 1000m from the cabinet to the DP before he replaced some overhead cabling, & 900m afterward (again from his JDSU).
Those attenuation values & reported D-side lengths could explain my current relatively low speeds (DS of 32084 K Attainable & 27131 K Sync speeds).
I THINK I may still have a potential HR issue somewhere in my D-side as I DID achieve actual download speeds of 32 Mb - 33 Mb for the first month (solid & stable connection).
Now it only averages around 22 - 23 Mb (on a good day, outside peak periods).
Unfortunately the engineer refused to carry out a TDR test to confirm that one way or the other, as he stated that the Pair Quality Test showed as LTOK.
I am unable to confirm what my reported attenuation & D-side lengths were at the time I was achieving the more reasonable speeds, but the original installing engineer did say that my connection's sync speed was around 35 Mb.
A previously visiting BT engineer told my that my D-side was around 820m in length, but that figure came from his laptop, not his JDSU.
Paul.
EDIT:-
It must be a really good day today:-
http://www.speedtest.net/result/1653680967.png
Edited by deleted (Sat 17-Dec-11 11:36:42)
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Hi Andrew, what ip profile You have ? What speed You have on speedtest.net ?
My stats
Attainable rate (kbit/s) 108296 35112
SNR margin (dB) 26 23.2
Line attenuation (dB) 0 0
Output power (dBmV) 12.8 -3.1
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After my FTTC installation at work, we have the following attainable rates according to the openreach modem
Downstream 132728
Upstream 41166
Cable length is about 50 metres according to the openreach engineer.
Andrew
Sweet - mine is about a similar distance. At least 6 months before they install FTTC though, possibly more.
(Another Andrew)
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Vaguely on the subject: will these ultra high attainables ever be actually usable? I know BT are planning a vdsl2 product capped at 80mbit, but is it relatively easy for them to increase that to 120mbit say?
In ye olde days, I remember adsl1 was capped at 8bmit, it simply wouldn't go above a certain frequency limit. Is that the case for vdsl2?
Thanks in advance to anyone who knows.
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I dont think we will see them push it as hard as adsl2+ got pushed because of new regulation now where 10% of customers have to be able to get the speed, whilst still soft its a rule which wasnt there before and will exist after april. adsl max didnt fall foul of the 10%, but adsl2+ certianly does. So next spring we should expect to see advertised adsl2+ products chance. FTTC in its current form at 40mbit is fine, I expect 80mbit will be just about fine, but 120mbit may be pushing it too far unless they deliberatly reject customers without good enough lines.
Edited by Chrysalis (Sat 17-Dec-11 21:05:18)
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Expect up to 100Mb/s from FTTC.
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After my FTTC installation at work, we have the following attainable rates according to the openreach modem
Downstream 132728
Upstream 41166
Cable length is about 50 metres according to the openreach engineer.
Andrew
Thats about what i got in the FTTC Stats thread just as the thread was locked.
I have an 80m'ish cable length http://i286.photobucket.com/albums/ll111/MrBelter/17...
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I wonder what these very short lines will produce when BT gets around to profile 30a. 200mbit seems quite plausible, although how do they market something that only 10% of people can benefit from?
Or is it more than 10% perhaps? I suppose in quite a few cities line length to the cabinet will be very small due to population density (especially those with lots of flats).
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I suppose in quite a few cities line length to the cabinet will be very small due to population density (especially those with lots of flats).
What an odd statement ? D-sides can be short or long, and living in a city is no guarantee of a shorter run.
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Think about it: if a cabinet serves x hundred people, and those people live in an area of higher population density, then inevitably the cabinet>property length will be shortened.
I can see this is the case in the centre of Edinburgh, which is all old tenements - there are BT cabinets everywhere.
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In reply to a post by Anonymous:
WHere you the same Anon that said " I suppose in quite a few cities line length to the cabinet will be very small due to population density", which has now become "inevitably"?
My broadband basic info/help site - www.robertos.me.uk
My domains,website and mail hosting - Tsohost. Internet connection - IDNet Home Starter Fibre. Live BQM.
"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
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In reply to a post by Anonymous:
I can see this is the case in the centre of Edinburgh, which is all old tenements - there are BT cabinets everywhere.
Glaswegians put dummies there because they know the population of Edinburgh are very dense.
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Think about it: if a cabinet serves x hundred people, and those people live in an area of higher population density, then inevitably the cabinet>property length will be shortened.
Why should the proximity of high density housing have any affect on cab location/D-side length ? It takes a very large new development to make BT consider fitting a new cabinet, the usual action is to feed it from an existing cab, where costs can be kept down.
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I think the issue is that we laymen have no idea what range of connectability PCPs have. Clearly there are many sizes, but how many lines can the large and small ones support? Roughly, of course.
Edit - for example, this is mine. There are clearly many hundreds of pairs visible when it is opened.
My broadband basic info/help site - www.robertos.me.uk
My domains,website and mail hosting - Tsohost. Internet connection - IDNet Home Starter Fibre. Live BQM.
"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
Edited by RobertoS (Tue 20-Dec-11 22:14:29)
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I'm moving house shortly, and took the effort to work out where FTTC was available (it was the only town in the county with fibre, and only 1 of the 3 exchanges have been upgraded), before looking at property.
When I mapped out the location of the cabinets, I found that they would tend to trail out from the exchange along major roads, and could even appear every 200-300 yards - but the postcodes covered would then spread out sideways a long way. It gave long, thin ribbons of coverage to each cabinet, at 90 degrees to the direction of the main road.
I suspect the same is true even in the denser cities - the cabinets might be close together along the main roads, but the distance each cabinet supports will still be quite long areas out at 90 degrees to the main roads.
In my current area, cabinet coverage was in more circular patches. The distances to the furthest locations then usually jogged around a little to get to the extremes.
But still, in both my current & next town, the maximum distance to cabinet seemed to be around 700 metres.
And, IIRC, BT's average is around 300 subscribers per cabinet. 25 million lines and 80,000 cabinets, I think.
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Think about it: if a cabinet serves x hundred people, and those people live in an area of higher population density, then inevitably the cabinet>property length will be shortened.
Why should the proximity of high density housing have any affect on cab location/D-side length ? It takes a very large new development to make BT consider fitting a new cabinet, the usual action is to feed it from an existing cab, where costs can be kept down.
The response to your previous post highlight two points:
(1) The silliness (in my opinion) of allowing anonymous posters. 
(2) That one or more of those anonymous posters does not know (or has failed to guess) your mode of employment. 
-----------------------------------------------------
100% Linux and, previously, Unix.
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Your numbers are in the ball park, 5500 exchanges, 85000 cabinets.
90% of lines within 1km of cable of the cabinet.
The big FTTC cabs can support 288 lines, and the sleeve type ones I think drop to 144. For future Ericsson showed off a small house brick sized MSAN that handled 10 lines, and could run off the power from copper pairs, i.e. no need for mains. This was some three years ago too
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The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
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(1) The silliness (in my opinion) of allowing anonymous posters.
(2) That one or more of those anonymous posters does not know (or has failed to guess) your mode of employment.
Hi burakkucat,
I know you are already aware of this, but for anyone else who may be interested, I find the forum at Kitz forum very useful as posters do need to be signed in.
BTW, the kitz forum has only this week started a dedicated FTTC & FTTH Issues section (& there does appear to be room for an active BT installation engineer at the moment).
Edited by deleted (Wed 21-Dec-11 17:57:40)
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