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[nat3s]

My router is reporting 54 db DS line attenuation. Having used several line speed prediction tools this suggests a potential 4mbs connection (which would be fantastic!). Unfortunately I seldom connect at anything over 400kbs and occasionally connect at 128 or lower. My line is generally stable and my router seldom loses an actual connection. It is just terribly slow most of the day / evening (peak / off peak times make absolutely no difference). My latency (ping) is great for gaming (around 30ms to UK servers).

The ADSL Exchange checker on this site reports the following for my postcode / telephone number:

        Exchange: Herne Bay     BT Code: NDHBA
        Location: Victoria Park,    CT6 5BH
        Distance:-    Direct:          2.8 km
     (appx)*    By Road:    4.18 km
     Status    
   ADSL enabled:    June 29, 2001
   DSL Max enabled:    March 30, 2006
   SDSL enabled :    Enabled
   21CN due : (PSTN)    No Info
   21CN WBC (Broadband)    Enabled 31.05.09
        Broadband Access Market    Broadband Access†    Market 3

    Fixed ADSL:      256 kbps      (0.3 Mb)
   DSL Max:      250 kbps    (0.3 Mb)
   21CN WBC :    Not Available    

The maximum speed check based on 54db attenuation reports:

Approx line length: 3.9km
dslMAX: 3904 kbps IP Profile: 3000 kbps
adsl2+(21CN): 4096 kbps IP Profile: 3000 kbps
adsl2+(LLU): 4096 kbps Throughput 3625 kbps

I was wondering why the BT estimated line speed (0.3 mb) differs so wildly from the attenuation predicted line speed (4 mb)? Does this suggest BT are aware of a fault with the line provided to my area? Is there anything that I can do as a consumer to improve my line speed or indeed anyone I can contact to see if the exchange is going to be upgraded / fixed in some way?

I have family that live less than a mile away that connect between 4-6 mb. The BT line speed check for their postcode is much more optomistic than mine.

Any advice / tips would be greatly appreciated

Thanks,

Nathan

EDIT: Forgot to add that my ISP is Zen internet (specifically opted for Zen due to their favourable reviews on the old ADSL Guide website).

[sevenlayermuddle]

The BT 'estimator' takes account of the actual line speeds that have been achieved for the line, so it's just telling you what you already know - that your line typically achieves something of the order of 400kbs. 

The Kitz checker, as you've discovered, predicts a much better speed for your attenuation.  It would appear likely  that something is badly wrong with your line or your (internal) wiring.

The first thing to do is to test from the test socket, if you have one, with all internal wiring disconnected, see
 http://www.kitz.co.uk/adsl/socket.htm

If the test socket make a dramatic difference, then it's fair to assume there's a problem with your internal wiring.  In that case, we can help you to track down any problems.

Conversely, if you get a lousy connection speed even from the test socket, it may indicate a line fault (in BT external wiring).  In that case you'd have to get your ISP to approach BT.  Alternatively, if the line is crackly (try the quiet line test on 17070) you can report it as a phone line (voice) fault to BT yourself.   Be aware however, that BT may charge you if they subsequently pin the blame on you.

It's also worth posting your full line stats, just in case there's anything that's not evident from your description of the problem. See
http://www.kitz.co.uk/adsl/frogstats.php

[kitz]

As mentioned linestats would be good.

The guestimator assumes the default target SNRM of 6dB.   
If your Target SNR is set higher by the DLM then this will have an impact of your connection speed.

[nat3s]

Thanks for the replies. Will take a look at my BT socket when I get in from work.

Here are my line stats reported by my router this morning:

     Connection Status    Connected
     US Margin    17
     DS Margin    10
     Modulation    MMODE
     LOS Errors    0
     DS Line Attenuation    53
     US Line Attenuation    63
     Path Mode    Interleaved

Thanks,

Nathan

[jeffbb]

Hi

   DS Line Attenuation    53
     US Line Attenuation    63

something wrong there normally US attenuation is about half of DS attenuation are you sure that these figures are not the wrong way round .
That would mean your DS is showing 63db , most routers can only display 63db maximum which of course means that the actual could be higher .
Regards Jeff

[kitz]

Weird

I was looking at MMODE as Id not seen that before for the modulation so did a google
... and one of the first things I noticed from someone elses stats is that they were showing practically the same weird upstream atten - linky.  
Wasnt the only one I found like that.   Firmware issue?

[nat3s]

The stats are correct. My US attenuation is definitely higher than my DS.

From memory (I'm posting from work), my US connection is a solid 488 kbps (I do not recall it connecting at anything other than this). Is it unusual for the US conn to connect at a higher rate despite the attenuation being higher?

When you say firmware, do you mean to say this could be a problem with my router (D-Link DSL G604T)?

Thanks,

Nathan

[duckson]

Its probably the router at fault, my 3COM Officeconnect (AR7 chipset) reports the US higher than the DS on mine.

[sevenlayermuddle]

To clear any ambiguity over your speed expectations, you could try the BT estimator with just a postcode, and no phone number.  If that predicts a much better figure, it would tend to suggest that your immediate neighbours are doing a lot better than you are, and so there's a good chance you'd be able to do better too (though nothing's certain).

If a prediction based on postcode alone is still low then all hope is not lost, though you'd have less cause for optimism.  If you know any of your immediate neighbours' phone numbers, there's nothing to stop you from snooping on their results at the BT Estimator, which could also be interesting.  In my own case, all my neighbours' numbers show a much poorer 'prediction' than I do, simply because I've optimised my internal wiring.

Regardless of all that, I'd still advise testing from the test socket as that can provide a quick and convincing indication as to whether or not there's an internal wiring fault causing problems.

[roseway]

My US attenuation is definitely higher than my DS.

Just to be clear, this must be a reporting error. Attenuation rises with increasing frequency - it's a combination of cable resistance and frequency-related effects such as cable inductance and capacitance. The upstream part of the signal uses lower frequencies than the downstream, so it can't really have a higher attenuation than the downstream (except in some implausible combination of faults).

[nat3s]

Thanks for the replies.

I've just run the BT line speed check using only my postcode and it returned the following:

    Fixed ADSL:      1024 kbps      (1 Mb)
   DSL Max:      2500 kbps    (2.5 Mb)
   21CN WBC :    2500 kbps    (2.5 Mb)

With my phone number added I get:

    Fixed ADSL:      256 kbps      (0.3 Mb)
   DSL Max:      250 kbps    (0.3 Mb)
   21CN WBC :    Not Available    

The RAG section returned this without my phone number:

    Fixed:     Long line green for 1Mbps, Red for 2Mbps
   radsl:    512Kbps and 256Kbps available
   MAX:    ADSL Max is available
   TPON:    No info in database
   Check:    No info for Postcode only search

And this with my phone number:

    Fixed:     1Mbps and 2Mbps not possible
   radsl:    Line has over 75dB loss, ADSL unlikely, but will be tested by an engineer on-site
   MAX:    ADSL Max is available
   TPON:    No info in database
   Check:    The check identified another service on your line which may prevent you from ordering a new ADSL connection. Examples are : Existing adsl connection, DACs, LLU, TPON etc

Should there be such a large variation within a single postcode sector?

Does this suggest it is the wiring in my house that is causing the fault?

EDIT: I will have a go at testing the BT socket on the weekend to establish if it is my wiring.

[jeffbb]

Hi

quote :  radsl:    Line has over 75dB loss, ADSL unlikely, but will be tested by an engineer on-site

well if this is true then that does not tie up with your quoted 54db attenuation !.Might even confirm your DS attenuation at 63 + 

As the general level around you is much better this suggests that your line/internal wiring  has a problem. Have you got a close neighbour that is on internet to check the speed of their connection. The closer the better .

a first step would be to check your wiring see this link
Regards Jeff 

[sevenlayermuddle]

   Fixed ADSL:      1024 kbps      (1 Mb)
   DSL Max:      2500 kbps    (2.5 Mb)
   21CN WBC :    2500 kbps    (2.5 Mb)

That would be consistent with  mid-50's attenuation so I'm inclined to think that's what it is.  I can't say why the RAG suggests otherwise.   I've never really paid much attention to the RAG section, it may just be a further reflection of the possibility that your line/wiring/router is behaving badly?

Should there be such a large variation within a single postcode sector?

It can happen.  Occasionally it may transpire that your line takes a vastly different route from your neighbours, which would be bad news as there's now't you can do about it.  More commonly, I suspect it shows that a line is just sub-optimal.  Mine showed results of less than 1Mbps before I fixed my own wiring, now mine shows 3Mbps.     My immediate neighbour, with same 55-56dB attenuation as me,  shows 500kbps, but that's because I know his internal wiring is a complete shambles (one of these days he'll let me fix it for him).

The most common thing to improve internal wiring, if you have any extensions, is just to disconnect the ring wire (or fit an iPlate or filtered faceplate, all amount to the same).   Any of these is would be almost certain to give you a massive boost, if you've not already done it.  But your performance is so far below par that I suspect there may be some other problem, all the more reason to try that test socket as it will allow you to see how high to set your sights.

Good luck,

7LM

BTW - I should've said in my initial reply - Welcome to the forum 

[b4dger]

Sorry if if I've missed it, but have the full line stats been posted?! 

I see results from numerous 'estimators' but don't think I've seen the actual line stats in full.

Attenuation/Sync/SNRM, results from speedtester.bt.com would also be useful.

Again apologies if I've missed things!