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slow speed - SNR Margin reset request

phil_the
Grafter
Posts: 27
Registered: ‎31-01-2018

slow speed - SNR Margin reset request

username: thehat (free-online)

Had very slow speed for about a week. Looks like SNR Margin is very high, possibly due to some powercuts and thunderstorms that weekend.

Would be very gateful if SNR Margin could be reset.

Thanks

Phil.

16 REPLIES 16
phil_the
Grafter
Posts: 27
Registered: ‎31-01-2018

Re: slow speed - SNR Margin reset request

Data rate: 1087/572 Maximum data rate: 1092/10028 Noise margin: 5.6/22.7 Line attenuation: 19.6/38.5

TheMightyAJ
Plusnet Alumni (retired)
Plusnet Alumni (retired)
Posts: 2,511
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Registered: ‎26-03-2018

Re: slow speed - SNR Margin reset request

Hi @phil_the,

I'm sorry to hear that you're experiencing issues with the connection. Whilst testing the line today I discovered an external phone fault that was affecting your services. I've raised a ticket response regarding this with further information and this can be viewed here.

If this post resolved your issue please click the 'This fixed my problem' button
 Alex H
 Plusnet Help Team
phil_the
Grafter
Posts: 27
Registered: ‎31-01-2018

Re: slow speed - SNR Margin reset request

OK Thanks

phil_the
Grafter
Posts: 27
Registered: ‎31-01-2018

Re: slow speed - SNR Margin reset request

I was out this morning. Connection seems to be back now, but still at slow speed. Is it possible to reset the SNR MARGIN? We've always had intermittent disconnections here, but I don't mind that as usually reconnects straight away.

jab1
Legend
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Registered: ‎24-02-2012

Re: slow speed - SNR Margin reset request

@phil_the I'm sure @TheMightyAJ will come back and say this, but there is little point in resetting the SNR until the phone fault is fixed - it will just go south again until that is done.

John
phil_the
Grafter
Posts: 27
Registered: ‎31-01-2018

Re: slow speed - SNR Margin reset request

Thanks.

I would have thought that might depend on if the fault is new or just how it's always been?

The weekend before last we had a number of power cuts due to a faulty ring on the electric cooker. There was also really strong winds and thunderstorms around that time. It is since then that the speed has gone right down, and I assume that is the main cause of the problem.

I didn't report it immediately because I thought it might come back on its own, and I was really busy with various things last week.

It seems a bit of a coincidence to me that there is also now an 'external line fault'. We have always had intermittent disconnections, so I'm wondering if this fault has been there for some time. It's great they're going to be looking into this, but if they're not going to be able to do anything until Friday, it would be nice if a tweak could be made to try and improve the speed in the meantime.

Download speed is down at half the upload speed, a fraction of what we normally get. I'm not an expert by any means but to me the attenuation value looks good, and doesn't seem to have changed much over last few days whenever I have looked at it. I'm sure if the margin was reduced I would get a decent speed again, even if it was temporary. 

phil

jab1
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Re: slow speed - SNR Margin reset request

I think I understand what you are saying there, but as @TheMightyAJ hasn't come back with any further information, I'm reluctant to comment further for fear of muudying the waters.

The only thing that might give us a clue in the meantime are your router statistics. Can you provide them?

John
phil_the
Grafter
Posts: 27
Registered: ‎31-01-2018

Re: slow speed - SNR Margin reset request

Statistics -- xDSL

 

 
Mode: ADSL_2plus    
Traffic Type: ATM    
Status: Up    
Link Power State: L0    
 
  Downstream Upstream    
Line Coding(Trellis): On On    
SNR Margin (1 dB): 21.7 6.7    
Attenuation (1 dB): 38.5 19.6    
Output Power (1 dBm): 0.0 12.7    
Attainable Rate (Kbps): 9648 1072    
 
  Path 0   Path 1  
  Downstream Upstream Downstream Upstream
Rate (Kbps): 572 1033 0 0
 
MSGc (# of bytes in overhead channel message): 99 10 0 0
B (# of bytes in Mux Data Frame): 2 23 0 0
M (# of Mux Data Frames in FEC Data Frame): 1 8 0 0
T (Mux Data Frames over sync bytes): 4 6 0 0
R (# of check bytes in FEC Data Frame): 16 8 0 0
S (ratio of FEC over PMD Data Frame length): 0.1538 5.9040 0.0 0.0
L (# of bits in PMD Data Frame): 988 271 0 0
D (interleaver depth): 192 4 0 0
Delay (msec): 7 6 0.0 0.0
INP (DMT symbol): 12.00 0.00 0.0 0.0
 
Super Frames: 2880078 2589448 0 0
Super Frame Errors: 7754 4031 0 0
RS Words: 618047560 3225755 0 0
RS Correctable Errors: 836 173 0 0
RS Uncorrectable Errors: 0 0 0 0
 
HEC Errors: 828 17986 0 0
OCD Errors: 0 0 0 0
LCD Errors: 0 0 0 0
Total Cells: 32068527 57844403 0 0
Data Cells: 251159 69824 0 0
Bit Errors: 0 9618 0 0
 
Total ES: 413 625    
Total SES: 200 20    
Total UAS: 45758 45564    

 

jab1
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Re: slow speed - SNR Margin reset request

Thanks for that, @phil_the . Sadly, it only confirms that your downstream SNR is at a silly level - we don't know why, and that your error rates appear to be high, but I'm no expert on interpreting this data, especially as you don't appear to be using a PN supplied router?

I can only suggest you await the PN Help Team response.

John
phil_the
Grafter
Posts: 27
Registered: ‎31-01-2018

Re: slow speed - SNR Margin reset request

It is a plusnet router. These stats are available from the expert_user.html page. Sorry, I assumed that's what you were asking for.

I posted the attenutation and margin values yesterday. As you say the SNR Margin is at a stupidly high value, hence my request for this to be reset.

My understanding is that repeated disconnections can cause the margin to be increased, and this results in slower speeds. There were repeated disconnections (due to powercuts) shortly before me noticing the internet was running excessively slowly.

Additionally, as I understand it, adverse weather conditions such as thunderstorms and heavy winds can also cause temporary problems that may result in an SNR margin increase. There were thunderstorms and heavy winds shortly before me noticing the internet was running excessively slowly.

From what I've read, temporary issues such as these can cause the SNR margin to be increased fairly quickly. It should eventually reduce again, but this can take a longer time. I've read several articles that recommend asking for the margin to be reduced / reset in this situation.

It seems that rather than simply reset the SNR margin, PN did some tests on my line and have identified a phone fault and the estimate time for this to be looked at is a couple of days. I'm not complaining, I'm sure the correct procedures have been followed, it's just a shame that it looks like I'm going to be stuck with these slow speeds until the phone line fault can be found and fixed. 😞

Phil.

jab1
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Re: slow speed - SNR Margin reset request

Okay - I don't have that router, so I'm not aware of the data it can provide. That was what I wanted, just not quite what I expected.Wink

Your understanding about repeated disconnections is absolutely correct, and under normal conditions, yes, the DLM will recover your 'normal' levels over time. It appears ,though, that the storms also affected the voice side of your connection, and there is no automatic repair facility for that.

You were lucky that PN did carry out those tests - had they merely reset your SNR, you would be back with another fault report fairly quickly, as that phone problem would not have gone away.

Sorry about the apparent extended resolution time, but the BTOR side of this - the repair - takes as long as it takes.TBH, I think you are lucky to get such a quick turn-around.

DISCLAIMER: I don't work for PN or BT - my comments/observations are merely based on many years of experience with computers and the internet.

John
SammyM
Plusnet Help Team
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Re: slow speed - SNR Margin reset request

Hello @phil_the,

 

We are sorry you are experiencing an issue with connection and can see we have raised a fault with our suppliers.

 

While our suppliers are working on this, I am afraid we would not make any changes to the line as these can be undone by any work carried out by the engineer. 

If this post resolved your issue please click the 'This fixed my problem' button
 Sammy M - Sheffield Team
 Plusnet Help Team
phil_the
Grafter
Posts: 27
Registered: ‎31-01-2018

Re: slow speed - SNR Margin reset request

Engineer visited today and has confirmed the fault on the line (battery leaking fault or something like that??). Unfortunately he's isolated it to a section of the line which is under the road, so could be a couple of weeks to get fixed as they have to dig it out 😞

Beyhive
Plusnet Alumni (retired)
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Posts: 722
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Registered: ‎25-02-2019

Re: slow speed - SNR Margin reset request

Hi @phil_the, we are sorry to hear that.

 

I have updated the fault ticket with more information regarding the fault. Please click here to view my response.

If this post resolved your issue please click the 'This fixed my problem' button
 Faris
 Plusnet Help Team