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[Grapefruit]

Couple of things.

One very interesting thing I notice is that the test report from Jan shows an attenuation of 59dB.  Was that using the same router do you know.

Can you please confirm how long youve been using the TP Link W-8960ND.  I want to rule out the possibility of a change of router in part being the reason for the increase in your attenuation from 59dB to 67.5dB

I would think unlikely. Most likely another TP Link (TD-W8961ND). I have the other router here though so could soon swap it over and see if there's a difference.

Ive sent an email to Sam so that we can hopefully get this amended in the Telephone Exchange to Postcode database.
I cant do an exact calculation - but a close estimate would be road length of 4.2km

I had an email back from Sam yesterday.  The database has been updated and the adslchecker should now be able to inform you more accurate information about your exchange. Thanks for advising us of the discrepancy.


I'll leave you to do a full check as I think there may have been a digit missing in your phone number.
Ive checked with your postcode and its now returning

Code: [Select]

Distance:- Direct:    3.31 km
  (appx)* By Road: 4.2 km

Now that I can get details on the map correctly, it looks like a pretty straight forward route between the exchange to your home mostly down one main road.  It obviously depends on location & routing between the green cab and your house that will determine how accurate the road to cable routing is, but having looked at the map of your area I doubt there's anyway that routing could go all around an estate for eg.   There are other factors that could come into play that may make this estimate not very accurate and thats the type of cable between your home and the green cab.
1) On long lines BT often use a thicker gauge of cable - this will give you a better attenuation.
2) There could be aluminium of the line - this makes your attenuation worse.


But the interesting observation that I make is an attenuation of 59dB equates to approx 4.3km of standard gauge cable. - link

 
HR faults can cause an increase in attenuation..  but that seems an awfully big increase and Id expect you be to be hearing more noise on the line than 'background noise'.

The sad news is that HR (High Resistance or High Open) faults are notoriously difficult for BT to track down and pin-point exactly which bit of cable or which joint is causing the problem. :/

Those distances are indeed correct.

Let me know if you'd like me to try swapping the router back and see what happens.


Edited by admin to fix broken tags

[kitz]

Let me know if you'd like me to try swapping the router back and see what happens.

Only if you know can get attenuation figures & line stats from both routers to be able to compare and eliminate it being a problem with the TP Link W-8960ND.
If you do ever take a router off. Make sure you power it down whilst the phone line cable is still plugged in (dont take the phone cable out first)..  and try to leave it powered down for at least 1/2hr before attempting to put the other router on.   This way the DLM is least likely to react.

The spike however is unlikely to be the router...  and Im unsure if swapping may be a good idea atm, only because it could involve 2 more resyncs and the DLM may clobber you further.

• Continue to monitor your line with DSLstats.  You can also just check if the SNRm dips when you use the phone.
• I would also like to see one of your graphs covering a 24hr period please to see if theres anything Ive missed.
  To do this go to Configuration > Graphs > Sampling and adjust the Time per Page. 

Dont forget to put it back later - and/or make sure that Snapshots >  Auto snapshots timing is NOT set to Use same timing as time per page.
I leave mine as unticked and set at 2hrs.  That way I can adjust graph periods without the danger of logs not being saved.

------

What I would also be looking to do if I were you, is contact Plusnet and let them know what's been discovered and noticed so far

1) I'd upload a copy of that 3:06pm spike as an attachment to your ticket.   Saying that youve noticed when the phone rings, your upstream SNRm takes a hit and this is what happened when they called you.   Plusnet will accept DSLstats graphs (& HG612modemstats) as evidence.

2) Id also bring to their attention your attenuation.  The test they ran in Jan showed an attenuation of 59dB whereas now its 67.5dB.  It may also be worthwhile re-uploading just in case they dont retain a copy that long.

3) They should also be able to see from their RADIUS logs that you are getting an awful lot of disconnects.

Then ask if they also suspect that there may be a HRfault. **

-------------------------------------


** I want to put the ball in their court first, because if an engineer comes out and he says 'no fault found' (which can happen with HR faults)  I dont want you to be billed.

BlackSheep (or anyone else) - can you perhaps think of anything from your side of things that could help?

Frequent Disconnections
Sharp spikes on the Upstream SNRm when phone rings
Loss of 8.5dB attenuation.

[Grapefruit]

Let me know if you'd like me to try swapping the router back and see what happens.

Only if you know can get attenuation figures & line stats from both routers to be able to compare and eliminate it being a problem with the TP Link W-8960ND.
If you do ever take a router off. Make sure you power it down whilst the phone line cable is still plugged in (dont take the phone cable out first)..  and try to leave it powered down for at least 1/2hr before attempting to put the other router on.   This way the DLM is least likely to react.

The spike however is unlikely to be the router...  and Im unsure if swapping may be a good idea atm, only because it could involve 2 more resyncs and the DLM may clobber you further.

Not a problem, I shall leave it 10 days until the "training period" ends and consider trying again then. I'm dubious about this training period though, as at no time has the downstream SNRM dropped to the 6db default level you mentioned. Furthermore, I have records with PlusNet tests going back a couple of years and all the time they set my MSR and FTR as the same figures as I've quoted earlier. Since then i've probably had 6-8 line resets.

• Continue to monitor your line with DSLstats.  You can also just check if the SNRm dips when you use the phone.
• I would also like to see one of your graphs covering a 24hr period please to see if theres anything Ive missed.
  To do this go to Configuration > Graphs > Sampling and adjust the Time per Page. 

Graph attached.

Dont forget to put it back later - and/or make sure that Snapshots >  Auto snapshots timing is NOT set to Use same timing as time per page.
I leave mine as unticked and set at 2hrs.  That way I can adjust graph periods without the danger of logs not being saved.

------

Good thinking. Auto snapshots would be a good plan.

What I would also be looking to do if I were you, is contact Plusnet and let them know what's been discovered and noticed so far

1) I'd upload a copy of that 3:06pm spike as an attachment to your ticket.   Saying that youve noticed when the phone rings, your upstream SNRm takes a hit and this is what happened when they called you.   Plusnet will accept DSLstats graphs (& HG612modemstats) as evidence.

2) Id also bring to their attention your attenuation.  The test they ran in Jan showed an attenuation of 59dB whereas now its 67.5dB.  It may also be worthwhile re-uploading just in case they dont retain a copy that long.

3) They should also be able to see from their RADIUS logs that you are getting an awful lot of disconnects.

Then ask if they also suspect that there may be a HRfault. **

Good thinking. They should have a record of the call at 15:06 so hopefully they can see the spike was caused by it. They are already aware of the attenuation issue you mention (strangely they mentioned it in a ticket update last night!) They suggested it might be due to the router being connected to a non-master socket...but I replied to tell them there is only one socket in the whole house.


Thanks again for your help!

[kitz]

as at no time has the downstream SNRM dropped to the 6db default level you mentioned.

Then I suspect it may not have happened yet.   Plusnet raise it with BTw who are the ones that reset it, so its not done immediately.

Graph attached.

Oops!   

They should have a record of the call at 15:06

Yep thats what I was hoping

strangely they mentioned it in a ticket update last night!

Thats good they noticed.  Its something that could easily be overlooked

[Grapefruit]

oops indeed!

[kitz]

Cheers, theres nothing in there that indicates an actual loss of sync. 
The downstream looks pretty normal.  Its just your upstream SNRm when the phone rings.

[Grapefruit]

Thanks. I think you're probably right about the higher SNR (and SNRM) causing the loss of speed. Given the downstream SNRM is set as high as it is, if that were reduced to the 6db norm then and my speed would rose by the resultant 400kbps you mentioned previously then this would account for the lost speed you say. The router change could be behind the SNR increase I guess.

[Black Sheep]

"BlackSheep (or anyone else) - can you perhaps think of anything from your side of things that could help?"

Hmm, not really, Kitz. You've more than adequately covered what grapefruit needs to do, by way of keeping logs and keeping PN aware. That way, if a future engineering charge is raised he will have supporting evidence to dispute it ?.

Unfortunately, (as we all know) it really is down to the type of engineer you get and his abilities. There is an extremely high chance that all the mandatory tests will pass, with the 'HR' being in its infancy and it's this type of issue that sees charges being raised.
My only advice from an engineering perspective, is if you do have request a visit then ask the engineer to ensure your circuit is reset to default values, and to then emulate the fault condition whilst his JDSU/EXFO is connected.

PN are owned by BT, and as such we can view the circuits 28-day history using WHOOSH and also perform the reset ourselves without needing to ring PN. Default values are required so that no 'masking' of errors occur when trying to emulate the fault condition. So, to re-cap ……. whilst the engineer is on-site, the circuit needs a full reset, then with his equipment monitoring the circuit ring the landline number and/or perform a QLT and see what effect this has on SNR and errors.     

[Black Sheep]

NB ……for information purposes, and I know there's a completely different debate to be had behind it ….. but the 'Named engineer' choice kicks in this month.

For an extra payment, the EU can request a certain engineer attend site. I can't find supporting documentation, but when we were first informed this was coming to fruition I think the extra charge was £50 ?? Don't shoot the messenger, and lets not hijack Grapefruits thread. I just thought it worth pointing out as an addendum to my comments above, regarding different engineers abilities. 

[kitz]

Thanks BS for your comments.  I know HR faults can be a pig to track down

[Grapefruit]

Thanks both for your help, it is greatly appreciated.

Is there any good software for tracking Ping? My speed seemed to be running slow so I decided to try a speedtest on my phone. It eventually failed after recording the Ping at over 3000! It's quite likely a router restart would fix it but I'm rather cautious given it's supposedly "training".

[kitz]

You are best testing ping from a PC connected by ethernet, as testing over wifi only introduces more latency.

I tend to use WinMTR as its lightweight, but PingPlotter is another favourite

http://wiki.kitz.co.uk/index.php/Network_tools

[Grapefruit]

Thanks. Here's some results so far. I don't know if it means anything. DSL stats seems to be showing fairly normal still. The only strange pattern i've picked out so far is that the upstream SNRM seems to stay high for 12hrs (midnight-ish to midday-ish) and then falls back again.

[kitz]

The only strange pattern i've picked out so far is that the upstream SNRM seems to stay high for 12hrs (midnight-ish to midday-ish) and then falls back again.

..  and the dips when the phone rang? 

As regards to the 1am to mid-day...  that to me looks like it something being turned on at noon and turns off at 1am that causes a very slight amount of EMI/RFI interference of 1dB.  It could be various things: heating, TV etc.  It may not even be in your home, but could be coming from a neighbour.

Still at 9dB?   If it doesnt change in the next day, Id give Plusnet a prod saying it doesnt appear to have been reset as your Target SNRm is still 9dB.
Normally Id expect the line to resync itself when the DLM gets reset, but you could just try yourself first.   If you do..  switch off the router and leave the modem cable plugged in.  Then if possible leave it powered down for 30 mins before switching back on again. 

[Grapefruit]

The only strange pattern i've picked out so far is that the upstream SNRM seems to stay high for 12hrs (midnight-ish to midday-ish) and then falls back again.

..  and the dips when the phone rang? 

As regards to the 1am to mid-day...  that to me looks like it something being turned on at noon and turns off at 1am that causes a very slight amount of EMI/RFI interference of 1dB.  It could be various things: heating, TV etc.  It may not even be in your home, but could be coming from a neighbour.

Still at 9dB?   If it doesnt change in the next day, Id give Plusnet a prod saying it doesnt appear to have been reset as your Target SNRm is still 9dB.
Normally Id expect the line to resync itself when the DLM gets reset, but you could just try yourself first.   If you do..  switch off the router and leave the modem cable plugged in.  Then if possible leave it powered down for 30 mins before switching back on again.

Haha, perhaps that should have read "The only other strange pattern...."

Thanks for explaining the midnight/midday. I can't think of anything off the top of my head but like you say could be a neighbour.

Yes, still 9db. I'll give PlusNet 24hrs to respond as apparently any replies to tickets push them to the back of the queue again! Worth trying to turn off, wait, turn on though.