Poor Connection speeds since migrating to ADSL2+

[ShadowHunter]

Hi.

I used to get a constant 6.8 Meg connection on ADSL1 but since migrating to ADSL2+ before Christmas I am now only synching at 6654 Kbps and am only getting 5.3 meg speeds on various speed tests sites (with no background apps connecting to the internet)...

I have a CRYSTAL clear phone line and am 835 metres from my exchange but my noise margin is 23.8 and has been around this mark since before Christmas.

I have tried plugging into the test socket, a different wireless router, a wired router, professional ADSL2+ filters, I've tried connecting from my netbook, my dads laptop and even my HTC hero but all give me the same poor download speeds.

I have reported it to IDNET many times and they sent a BT engineer out the week before Christmas and they dug up the road but it made no difference.

IDNET now say my line cannot support any higher than 5.3 megs but I was getting a constant 6.8 Megs with IDNET on ADSL1 and did get a 12.5 meg connection on ADSL2+ for a few weeks, so I know higher, stable speeds are possible.

Please can anyone give any further advise on this as I don't want to leave IDNET but will have to look elsewhere if this can't be resolved soon as I feel I have put up with it long enough..

[Rik]

Hi and welcome to the forum.

If BT have worked on the cable, it suggests an acknowledged fault, so moving ISPs will take the fault with you. I suspect BT have tried to improve things and failed, so have decreed that that speed is all your line can support. What downstream noise margin does the router report?

[Simon]

  Many people can only dream of speeds like yours, but someone will be along soon to offer some advice. 

[Simon]

As I said...

[Niall]

I don't think it's IDnet. Some people see less stable lines with ADSL2+ as it's more sensitive to noise (apparently, I read that on a forum, so it may not be true!).

My sisters connection is ADSL2+ on the same exchange as me and they have a constantly dropping phone line and the DSL drops randomly too. When I see a problem, like a slight drop in speed and my router re-syncs, my sister who lives less than half a mile away (but only about 400 yards further from the exchange than me) has an almost complete loss of internet. In the last week or so it's been terrible for them, with either the phone not working at all, or the internet connection being totally lost. On Saturday they had no internet all day.

IDnet are looking into that for them, and an engineer is coming out to test their line. I'm not sure what the problem is for them as 30 yards from them, our friends have a crystal clear line and only see the issues that I do.

Personally I just think ADSL2+ is far less stable than the up to 8mb service, unless you've got an extremely good line with an exchange that has no problems.

{edit} Blimey, 3 people posted while I was typing

[Rik]

I have a CRYSTAL clear phone line and am 835 metres from my exchange but my noise margin is 23.8 and has been around this mark since before Christmas.

Further thought. The maximum target noise margin BT sets is 15db, so your higher figure suggests noise pickup.

[Niall]

What causes noise on a line Rik? I was talking to my sisters other half the other day about this, and I can only remember back in the 56k days when you could request BT to "turn up the volume" on a line to increase your speed. I have no idea if something at the BT end is altered that can cause issues on the line for your ADSL, but it's the only thing I can think of

[Rik]

Electrical equipment in the main, Niall, inside or outside the premises.

[Ray]

 

[Niall]

Hmm. My sisters router (the old rock solid Zyxel one I used previous to my Netgear) sits next to the PC, and there are a couple of speakers in the room, but it's nothing more than I have in mine so I doubt it's that causing it.

Personally I think they're having line issues as the phone is dropping out too. I've given them the new filters that I had spare and that made absolutely no difference. That leaves the internal wiring which I believe they will be replacing after the engineer has been, just to make certain everything is as good as it can be.

That being said, their profile was 5800ish before the problems started, where as mine is 11000, dropping to 10000ish when something odd happens in this area, which oddly increases my upstream speed. I suppose that's a limit of the line itself. Still, as it's only about 400 yards further from the exchange, basically same distance in a straight line, then an additional right turn! I really can't see why they would have such a different speed to me in more or less the same distance on the same exchange if it isn't a line fault.

[Rik]

IDNET now say my line cannot support any higher than 5.3 megs but I was getting a constant 6.8 Megs with IDNET on ADSL1 and did get a 12.5 meg connection on ADSL2+ for a few weeks, so I know higher, stable speeds are possible.

I've had a chat with support about your problem. DLM has banded your profile, and you're getting the top end of that banding. Banding is introduced as a stabilisation tool when the error count is high. IDNet are requesting that the banding be removed, which should give you an improvement within a few hours. However, if the speed than drops again, DLM is still unhappy with the error count.

In the meantime it will pay you to check for any noise pickup within the house. What else is connected to the phone line, how many socket do you have and how is the router connected, flat or round cable?

[Rik]

That being said, their profile was 5800ish before the problems started, where as mine is 11000, dropping to 10000ish when something odd happens in this area, which oddly increases my upstream speed. I suppose that's a limit of the line itself. Still, as it's only about 400 yards further from the exchange, basically same distance in a straight line, then an additional right turn! I really can't see why they would have such a different speed to me in more or less the same distance on the same exchange if it isn't a line fault.

High error count due to noise pickup is the most likely cause, Niall. What are the respective d/s attenuation figures?

[Niall]

Super Rik to the rescue (with a bit of help from support )  

I've just got off the phone to my sisters other half and BT have replaced something outside the house, stating it was short circuiting. It also looks like the internal wiring is a bit knackered and old, causing problems with noise. Hopefully it'll be sorted soon

[Rik]

If the line is dropping out, there's a real chance BT will fix it. 

[Niall]

I think they have from what I was just told. When he gets over his cold, he shall be buying lots of new cabling for the house. I think, from what I've heard/seen that it should resolve the issue. There's nothing else it really could be.

[Rik]

Not really, unless there some heavy electrical plant along the route of the line.

[Niall]

There's nothing like that near the town centre. All major things like that are nearer the industrial estate about 4 miles away, thankfully!

[Steve]

Hi ShadowHunter


I think you got some advice earlier on if you can find it


PS Did someone forget something?

[ShadowHunter]

Blimey Rik !!


Couldn't believe it when I logged on tonight..

Synching at 16247 and just did a speed test and got this result:-

http://www.speedtest.bbmax.co.uk/results.php?t=1269551905&v=9574778

(And if I haven't linked to that correctly, it's a download speed of 13643 Kbps !!!)



Now that's what I call an improvement!!

Just got to pray now that it keeps at that level as I've already seen errors on my Router's stats...

Line Mode   ADSL2+       Line State   Show Time   
Line Power State   L0       Line Up Time   00:23:32:11   
Line Coding   Trellis On       Line Up Count   1   
   
Statistics   Downstream   Upstream   
Line Rate   16247 Kbps   834 Kbps   
Noise Margin   6.1 dB   10.5 dB   
Line Attenuation   30.0 dB   13.9 dB   
Output Power   20.1 dBm   12.4 dBm   
MSGC (number in overhead channel data)   70   24   
B (number of bytes in Mux Frame)   142   34   
M (number of Mux Frames in FEC Frame)   1   2   
T (Mux Frames over sync bytes)   3   4   
R (number of check bytes in FEC Frame)   12   16   
S (ratio of FEC over PMD Frame length)   0.2810   2.6667   
L (number of bits in PMD Frame)   4413   258   
D (interleaver depth)   96   8   
Delay   6 msec   5 msec   
Super Frames   5133698    5133696    
Super Frame Errors   89    3    
RS Words   1170483208    174545664    
RS Correctable Errors   930350    103    
RS Uncorrectable Errors   1870    0    
HEC Errors   81    0    
OCD Errors   1    0    
LCD Errors   0    0    
ES Errors   0    0

Do these stats indicate any possible causes for the problems I have been experiencing? and do you think my speeds will gradually slow down again if these errors continue?

Thanks again!!

[Rik]

That error count looks OK for the up time on the router. Hopefully, problem solved. 

[ShadowHunter]

Hi Rik !

After the amazing results you had before do you think you could work some of your magic again?

After enjoying my high sync rate and getting 14 or 15000+ Kbps since my last post I returned from a 2 week holiday (during which my router was powered off) only to find that my sync rate had dropped to around 8000 Kbps.. it has since climbed to 11670 but my noise margin has risen from its stable 6.1 dB (since my last post) to it's current 13.4 dB.. and after giving it a few more weeks, my sync rate doesn't seem to want to climb any higher..

It's been stable for the last 6 months so I'm assuming that having my router off for the 2 weeks was seen at the exchange as a loss of sync and it upped my noise margin to compensate but I KNOW that it can support these higher speeds as it has been doing a great job of it!!

I appreciate this sounds a little greedy when others are struggling to get even a fraction of this but we all want the best speed that we can achieve and I am sure with a little of your magic my speeds can return to their former glory, which will hopefully stop the buffering i'm getting on BBC iplayer and the like.

Many thanks in advance

Neil.

[Rik]

Hi Neil, powering the router off would not have this effect - in fact I always advise people to power down routers while they're away.

Can you run a BT speedtest for me and post that and your router's stats (sync speed, noise margin and attenuation).

[ShadowHunter]

Hi Rik..

BT test results are as follows:-

Download speed achieved during the test was - 8992 Kbps
For your connection, the acceptable range of speedsis 2000-21000 Kbps.
Additional Information:
Your DSL Connection Rate :11668 Kbps(DOWN-STREAM), 828 Kbps(UP-STREAM)
IP Profile for your line is - 9000 Kbps
The throughput of Best Efforts (BE) classes achieved during the test is - 14.4:19.43:66.17 (SBE:NBE:PBE)
These figures represent the ratio while sententiously passing Sub BE, Normal BE and Priority BE marked traffic.

Router stats:-


Line Mode   ADSL2+       Line State   Show Time   
   Line Power State   L0       Line Up Time   00:04:45:26   
   Line Coding   Trellis On       Line Up Count   1   
   
   Statistics   Downstream   Upstream   
   Line Rate   11670 Kbps   828 Kbps   
   Noise Margin   13.4 dB   7.8 dB   
   Line Attenuation   30.5 dB   14.3 dB   
   Output Power   20.9 dBm   12.4 dBm   
   MSGC (number in overhead channel data)   61   24   
   B (number of bytes in Mux Frame)   174   34   
   M (number of Mux Frames in FEC Frame)   1   2   
   T (Mux Frames over sync bytes)   2   2   
   R (number of check bytes in FEC Frame)   14   16   
   S (ratio of FEC over PMD Frame length)   0.4785   2.6667   
   L (number of bits in PMD Frame)   3160   258   
   D (interleaver depth)   64   8   
   Delay   7 msec   5 msec   
   Super Frames   1068381    1068379    
   Super Frame Errors   3    319    
   RS Words   143163160    36324886    
   RS Correctable Errors   202278    7066    
   RS Uncorrectable Errors   70    0    
   HEC Errors   3    0    
   OCD Errors   0    0    
   LCD Errors   0    0    
   ES Errors   0    0    

So my download speed is around 4500 Kbps slower than what I have been enjoying since my last post..

Thanks again!

Neil

[Rik]

Your profile is 1M slow for your sync speed, otherwise throughput looks OK. Noise margin has risen, which suggests line instability.

Can you repeat the BT speed test tomorrow (after tonight's engineering work) and I'll then have a word with support. Meantime, if you can move to the test socket, disconnect everything else from the line and check the router stats again, that would be helpful.

[ShadowHunter]

Will do !

Thanks again Rik !

Neil.