Poor Connection speeds since migrating to ADSL2+

[Rik]

NP.

Until we get tonight out of the way, we're not sure whether we're chasing shadows, it's major work BT are doing. It may have no effect on your speed, but it makes sense to look again once they're finished.

[ShadowHunter]

Hi Rik..

Stats tonight (plugged in via BT test socket with nothing else on line) are as follows:-

Line Mode   ADSL2+       Line State   Show Time   
   Line Power State   L0       Line Up Time   00:00:00:23   
   Line Coding   Trellis On       Line Up Count   1   
   
   Statistics   Downstream   Upstream   
   Line Rate   11007 Kbps   828 Kbps   
   Noise Margin   14.7 dB   8.7 dB   
   Line Attenuation   30.0 dB   14.3 dB   
   Output Power   20.7 dBm   12.4 dBm   
   MSGC (number in overhead channel data)   64   24   
   B (number of bytes in Mux Frame)   158   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)   12   16   
   S (ratio of FEC over PMD Frame length)   0.4608   2.6667   
   L (number of bits in PMD Frame)   2969   258   
   D (interleaver depth)   64   8   
   Delay   7 msec   5 msec   
   Super Frames   1429    1427    
   Super Frame Errors   0    2447    
   RS Words   200198    48518    
   RS Correctable Errors   0    7977    
   RS Uncorrectable Errors   0    0    
   HEC Errors   0    0    
   OCD Errors   0    0    
   LCD Errors   0    0    
   ES Errors   0    0

Speed test is:-


Download speedachieved during the test was - 10026 Kbps
For your connection, the acceptable range of speedsis 2000-21000 Kbps.
Additional Information:
Your DSL Connection Rate :11004 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 - 16.46:25.48:58.06 (SBE:NBE:PBE)
These figures represent the ratio while sententiously passing Sub BE, Normal BE and Priority BE marked traffic.

Download speeds seem slightly higher even though Sync rate has gone down and noise margin has gone up??

Still nowhere near the 14000+ speeds I have been getting for the last 6 months since you got suport to tweak it last.

Regards

Neil.

[Steve]

I dont think we see Rik again until tomorrow, but it looks like noise pick up from somewhere. If you can leave it in the test socket and see if it's stable with no resyncs you've a chance of increasing your sync. Unfortunately adsl2+ is much sensitive to noise than adslmax so it's not easy to solve.

[esh]

This is very interesting. I get a fairly static 6.6Mbit on ADSL1 (the theoretical max being 7.1Mbit I believe) so I always assumed the wiring and everything was good here... interesting to know that going up to ADSL2 can cause so many issues. I really will think twice (three times?) before my exchange is upgraded....next year.

Following with interest; keep us updated.

[gingerjedi]

I can only dream of the speeds you're getting, look what I've had since 2:00 PM (see sig).

On the plus side it's the first time its managed to stay connected for more than 20 minutes.

[Niall]

I'm still baffled as to what happened to my line about a month ago when I had a LOT of noise on my line, and a lot of problems, then it went away by itself and now I get nearly 2mb more download, and my upload is over 1100 now

[klipp]

Gingerjedi a few months ago my upload was also higher than my download.  Turned out my netgear was dying.

[Rik]

This is very interesting. I get a fairly static 6.6Mbit on ADSL1 (the theoretical max being 7.1Mbit I believe) so I always assumed the wiring and everything was good here... interesting to know that going up to ADSL2 can cause so many issues. I really will think twice (three times?) before my exchange is upgraded....next year.

Following with interest; keep us updated.

Most people do gain, Esh, I went from 2-2.5 to 3.5-4, and haven't had many stability problems, the more so since I took part in the trial where ISPs could override DLM (to be rolled out soon).

[Rik]

Still nowhere near the 14000+ speeds I have been getting for the last 6 months since you got suport to tweak it last.

Hi Neil

As far as I can gather, your line has never been stable at 14M, and the BT checker shows its rate as being 9M now.

[klipp]

where ISPs could override DLM (to be rolled out soon)

OMG really?  That would be amazing.  I think the current system is terrible where users feel paranoid about restarting their routers for fear of BT punishing them with SNR increases.  Any news on when this new system will be introduce and how it would work?  Will we be allowed to select our own SNR?

[Rik]

No idea on date as yet. ISPs will decide the SNR, based on what they see. In my case, we tried 3db but it was unstable, so settled on 6db. I was able to go to fast path, which DLM had always switched to interleaved previously.

[esh]

That does sound rather neat. It gets my seal of approval! I'm sure you're waiting on BT of course, so we'll get this feature when we have FTTH.

[Rik]

Exactly.

[jezuk1]

I've had some interesting experiences with ADSL2+ and the speed it runs at. When I first had it installed I remember the sync speed came in around 14Mbps. Over a few months the speed dropped down to 6Mbps (I don't really know how quickly this happened unfortunately as I wasn't watching or logging it) however one day I was downloading a file and noticed the slow speeds, logged into the router to discover this fact.

I spent alot of time checking phone lines, noise levels, etc without really revealing any problems (again Simon @ Idnet was extremely helpful). In the end we reset the banding (variable speed adaption mechanism) on the line and I watched again what happened however this time around, instead of turning my router off at night I left it on permanently. At first, again it synced at 14ish Mbps but this time it has stayed there for a few months now, perfectly happy and never dropping a sync. Sometimes the exchange tries to up the speed to 15-16Mbps but after a day or two it decides "no" and it goes back down to 14. Every now and again it drops to 13Mbps but after a few weeks of uptime, again the exchange makes a reset and it's back to 14 which seems to be the magic number.

So why did the speed drop down to 6Mbps? Well truth is that I probably will never know, certainly after resetting the banding I've had much better speeds. Nothing has changed in my premisis since the start (wiring, etc). My personal suspicion is that turning my router off at night wasn't helping - perhaps the equipment in the exchange considered my line to be unstable, and increased the noise margin accordingly (who knows!). I think the variable speed adaption is all very nice in general, but not so much so when it decides to run a line at 6Mbps when it's proven to be capable of 14Mbps.

Jez

[Rik]

Thanks for that, Jez. I think you're right. BT likes 24/7 routers even though, in theory, shutting them off at night should have no impact.

[ShadowHunter]

Hi.

I'm in agreement with Jezuk1... although switching off my router every night (or rather my dad switching off my router every night to 'save on the electricity', despite my protests) didn't seem to have a negative affect on my sync rate until recently when it was off for those 2 weeks whilst I was abroad..

I think I may've been over stretching my positivity to say I was getting a stable 14M connection Rik but it's definately been averaging 12+M speeds since my first round of posts and the fact is, it's now 8983 Kbps.. so the fact remains that i've definitely lost a big chunk of speed from somewhere..

Do you think BT have reset my banding to how it was before the speed improvements?

And why should my sync rate have fallen from it's stable 16247 with a noise margin of 6.1 dB to it's current 11500 with a noise margin of over 14 dB?

My line is still crystal clear with nothing else attached, I'm plugged into the test socket and have again tried different laptops, pcs, wired routers and filters... the only thing that changed was that my router got turned off for more than it's usual overnight sleep so that must have something to do with it surely?

Do you think my speeds will climb back up if I can persuade my dad to leave my router on for a few days?

Or if I can persuade Rik to get my banding reset again?



As with Jezuk1.. I'm sure that's the only thing that will push my speeds back up again..

Thanks again

Neil.

[Steve]

I'm not aware of a band around that sync rate I think it's just related to the raised noise margin. What I do know is that the exchange will not drop your margin if you keep turning it off every night. It needs a few days of stability with no resyncs.

[Rik]

What Steve says, Neil.

[ShadowHunter]

Cool..

So my sync rate has now dropped to 7127 Kbps, my noise margin has risen to 21.3 dB and my download speed is now 3801 Kbps with an IP profile of 350 Kbps.. (that's what BT tester reports!) and all because my dad turns my router off every night??

Download speedachieved during the test was - 3801 Kbps
For your connection, the acceptable range of speedsis 100-500 Kbps.
Additional Information:
Your DSL Connection Rate :7124 Kbps(DOWN-STREAM), 828 Kbps(UP-STREAM)
IP Profile for your line is - 350 Kbps
The throughput of Best Efforts (BE) classes achieved during the test is - 9.56:24.01:66.43 (SBE:NBE:PBE)
These figures represent the ratio while sententiously passing Sub BE, Normal BE and Priority BE marked traffic.

?

So are you saying that my speeds will just get slower and slower ? (unless I can glue the routers plug socket into the wall?)

[Rik]

No, but it's not helping. I'd bet there's another, more major, noise problem going on.

What else is connected to the phone line, and is the router on an extension, or plugged straight into the master socket. (Apologies if you've already said, I've been in here 12 hours today, and I couldn't spot in while scanning the thread.)

[cavillas]

I sometimes think that all the turning off and on of routers can lead to solder joints breaking down or other smaller components breaking down or degrading.  This sort of thing can lead to the sorts of results some people are seeing.  It could be a case of quality control in the long term useage not being up to scratch.

[Simon]

Interesting thought, Alf.  I wonder, though, if the same argument could be applied to leaving components on 24/7, given the heat some of them generate?  Trouble is, these days, nothing is built to last.

[esh]

Devices of this kind tend to reach their thermal equilibrium quite rapidly; that is to say, leaving them on an hour would result in the same temperature as 24 hours assuming the environment does to change significantly. Inside a lot of networking equipment these days isn't very much at all -- a very sparse PCB with a couple chips soldered on and maybe a few caps and resistors tied to the physical ports. If the temperatures get very high then Alf is correct, if the substrate on the chips is not of sufficient quality then the constant heating/cooling puts strain on the solder points which can eventually break. Usually this would have to reach 80+ degrees in the immediate environment, which is why such an issue isn't too uncommon with graphics chips. Many of these vendors actually create extra solder points to cope with some breaking. Circuit connections within the PCB are another potential factor but less likely. Capacitors do tend to go from time to time, diodes especially, which can then muck up logic chips and the like, but as I said it's more likely everything just runs on an embedded processor rather than have lots of chips on a board now.

[ShadowHunter]

Sorry..

I've not been on my pc for a bit..

The router is connected to the mains via a 4 way surge protector, although nothing else is plugged into the 4 way extension.

My router is plugged into the only BT socket we have in the house via an 'ADSL Nation XF-1e professional ADSL2+' filter, it has one phone connected to it too but the line is still CRYSTAL clear!

I did notice though that Trellis is now set to 'Off' on my line when it was set to 'ON' before if that makes a difference!?

My sync rate is still 7127 Kbps and my noise margin is 20.8db.

I'm putting my dad forward for a job at IDNET as he's suddenly turned from a technophobe to a broadband expert having just told me that "It's a load of rubbish" that him turning my router off every night is not helping with the speed!




Thanks again!

[Rik]

You might want to try it without a surge protector. Poorly designed suppressors can cause low voltage problems for routers.