Kitz ADSL Broadband Information
adsl spacer  
Support this site
Home Broadband ISPs Tech Routers Wiki Forum
 
     
   Compare ISP   Rate your ISP
   Glossary   Glossary
 
Please login or register.

Login with username, password and session length
Advanced search  

News:

Pages: [1] 2

Author Topic: Is this normal after switching ISP's???  (Read 3848 times)

Zenfield

  • Member
  • **
  • Posts: 21
Is this normal after switching ISP's???
« on: May 02, 2018, 02:47:29 PM »

Hi all,

So i've just changed over ISP's from the 1st of May and have been keeping a key eye on my stats. One thing that stood out to me was the upstream SNRM bands. I know ive made a post prior to this querying it but for some reason some interesting things have developed since then. As you can see from my attached graph that my U1 band is all over the place. When i go to see the signal attenuation it shows the U1 value as N/A. Is this normal after a DLM reset due to me changing providers?? As it seemed steady when I was with my previous ISP.

Any thoughts and insight would be largely appreciated :)

Thanks in advance

Logged

Zenfield

  • Member
  • **
  • Posts: 21
Re: Is this normal after switching ISP's???
« Reply #1 on: May 02, 2018, 02:48:44 PM »

Also, If anyone needs any other information with regards to stats feel free to ask and ill be more than happy to provide them.

Thanks again :)
Logged

burakkucat

  • Respected
  • Senior Kitizen
  • *
  • Posts: 38300
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: Is this normal after switching ISP's???
« Reply #2 on: May 02, 2018, 11:06:35 PM »

That is certainly odd looking and not something I would expect to see as a result of a change of ISP. Does that continue; is it continuous?

Often, when a joint is failing -- going either HR or semi-conductive -- a sudden downturn in the SNR of the US1 band will be seen when a resistive (& inductive) load is applied to the circuit (i.e. using the telephone) which then reverts when the load is removed.

I'll suggest that you perform a quiet line test by making a call to 17070 and taking the relevant option from the presented menu. (That facility is not available to LLU'd lines.) There should be total silence but the circuit should still appear to be electrically "live".
Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

re0

  • Reg Member
  • ***
  • Posts: 840
Re: Is this normal after switching ISP's???
« Reply #3 on: May 03, 2018, 01:16:36 AM »

I agree with b*cat. It's not something I would expect to see either.

I am struggling to remember whether the lack of a value for signal attenuation on a band is indicative of nothing being allocated in that band or whether it is something else (or even a modem bug). But without thinking too much into it, I am not sure how U0 and U2 could satisfy 20 Mbps on this line (well, it IS possible, but then it would imply a short, clean line with virtually no crosstalk; though in such a case why would U1 be so weak?).

In any case, it would be nice to see your full graphed stats from something like HG612 Modem Stats https://kitz.co.uk/routers/hg612stats.htm if your modem supports it.

Nice attenuations by the way. Almost identical in length to my line. ;D

Edited to correct "router" to "modem".
« Last Edit: May 03, 2018, 02:13:37 AM by re0 »
Logged
ISP: Gigaclear - Hyperfast 900 (up to 940 Mbps symmetrical)

Ixel

  • Kitizen
  • ****
  • Posts: 1282
Re: Is this normal after switching ISP's???
« Reply #4 on: May 03, 2018, 01:20:33 AM »

That looks pretty strange. I've never seen a connection with U0 and U2, but not U1 (signal attenuation N/A). I'm curious to know what the bitloading and SNR graphs look like if that's possible to share.
Logged

Zenfield

  • Member
  • **
  • Posts: 21
Re: Is this normal after switching ISP's???
« Reply #5 on: May 03, 2018, 05:02:19 AM »

That is certainly odd looking and not something I would expect to see as a result of a change of ISP. Does that continue; is it continuous?

Yes it is, ive been running dslstats all day and it has hardly changed.

In any case, it would be nice to see your full graphed stats from something like HG612 Modem Stats https://kitz.co.uk/routers/hg612stats.htm if your modem supports it.

Nice attenuations by the way. Almost identical in length to my line. ;D

Attached as per request

That looks pretty strange. I've never seen a connection with U0 and U2, but not U1 (signal attenuation N/A). I'm curious to know what the bitloading and SNR graphs look like if that's possible to share.

Yeah thats not a problem.

Logged

Zenfield

  • Member
  • **
  • Posts: 21
Re: Is this normal after switching ISP's???
« Reply #6 on: May 03, 2018, 05:04:33 AM »

Thanks for all the input guys, i really appreciate the insight :)

Here are a few more stats ive pulled as one post only allows me to attach 3 files unfortunately :(
Logged

Zenfield

  • Member
  • **
  • Posts: 21
Re: Is this normal after switching ISP's???
« Reply #7 on: May 03, 2018, 05:07:17 AM »

Last one I promise..

Logged

Ixel

  • Kitizen
  • ****
  • Posts: 1282
Re: Is this normal after switching ISP's???
« Reply #8 on: May 03, 2018, 10:22:25 AM »

Well that looks like it answers my question. I think U1 isn't really in use because of UPBO and your connection doesn't need hardly any bits in U1 anyway by the looks of it. Still slightly puzzled why U1 SNR is fluctuating as much as it is, that's one I can't answer. Hlog appears relatively smooth, not perfect but in my opinion I don't see any real issues with it that might highlight an issue with the circuit. QLN looks not too bad too I believe.

Best wait for more comments, don't solely go on what I say as someone else may have noticed something I didn't or have a slightly different opinion :).
Logged

re0

  • Reg Member
  • ***
  • Posts: 840
Re: Is this normal after switching ISP's???
« Reply #9 on: May 03, 2018, 10:22:44 AM »

Thanks for posting that. This gives a clearer image. This is almost as I predicted. Perhaps U1 was not allocated at sync but bitswapped into it after?

The QLN shows that U1 is a bit noisy (which is, of course, due to interference), hence why the SNR is a bit lower and not smooth here, and it would explain why a lot of bitswapping is occurring to maintain a minimum SNR margin of 6 dB on the tones in that band. Everything else checks out as being normal (though someone here will point out if there is something else of importance).

Let me ask the following:
  • What modem are you using?
  • What filter are you using?
  • Are you currently plugged into the master socket or a slave socket?
Reference to question 3, if you are using a slave socket then I would suggest using the master socket (main socket, first point of entry for the copper pair). You can use https://kitz.co.uk/adsl/socket.htm and https://kitz.co.uk/adsl/btsockets.htm as guides to finding your master socket. I would also highly suggest that you plug the filter directly into the test socket (as pictured clearly in the first provided link) as this eliminates any internal socket wiring issues. Once you have done that, post QLN, bitloading and SNRM per band.

Are you getting any significant errors? I don't know how long you have been running DSLstats for, but the MTBE (Mean Time Between Errors; higher is better) I can see is approx. 260 on the downstream and 520 on the upstream. So the DLM certainly isn't going to be making any negative changes based on what we know.

I cannot comment on whether this constitutes a fault with the line necessarily since, while U1 looks to be impacted and subject to interference, the sync speed is not impacted and has a decent margin overall in the bands. I have confidence that you're always going to receive 20 Mbps upstream. You could request a line test from the ISP, but most "big" ISPs will have support (1st line) that will question "why?" since you have no visible deterioration to sync speed or errors. But you could still give it a go (though there is probably no need) after you've gone ahead and done what has been suggested by people on the forum.

Edited to correct "lower" to "higher". :doh:
« Last Edit: May 03, 2018, 11:10:42 AM by re0 »
Logged
ISP: Gigaclear - Hyperfast 900 (up to 940 Mbps symmetrical)

re0

  • Reg Member
  • ***
  • Posts: 840
Re: Is this normal after switching ISP's???
« Reply #10 on: May 03, 2018, 10:42:55 AM »

I think U1 isn't really in use because of UPBO and your connection doesn't need hardly any bits in U1 anyway by the looks of it.
Quite likely, though it seems fairly extreme in the OP's case. My line is similar to the OP's in terms of distance (<200m) and the SNR in U1 almost reaches 30, while theirs is no higher than about 16 (of course, I am referring to SNR as a figure and NOT a margin in this case). I understand it's not a direct comparison as each line is unique, but for example.

Still slightly puzzled why U1 SNR is fluctuating as much as it is, that's one I can't answer.
Because so few bits are bitswapping quite often, leading to a value that is shifting by a decent margin quite erratically.
Logged
ISP: Gigaclear - Hyperfast 900 (up to 940 Mbps symmetrical)

Zenfield

  • Member
  • **
  • Posts: 21
Re: Is this normal after switching ISP's???
« Reply #11 on: May 04, 2018, 02:49:42 PM »

UPDATE:

So yesterday afternoon I had the electrical board come and turn the power off to repair a faulty joint outside my house. I dont know if this had any adverse effect to my line but once power was restored g.inp was applied and the upstream bands had aligned correctly.



Logged

Zenfield

  • Member
  • **
  • Posts: 21
Re: Is this normal after switching ISP's???
« Reply #12 on: May 04, 2018, 02:51:35 PM »

A few more stats..
Logged

Zenfield

  • Member
  • **
  • Posts: 21
Re: Is this normal after switching ISP's???
« Reply #13 on: May 04, 2018, 02:56:29 PM »

Let me ask the following:
  • What modem are you using?
  • What filter are you using?
  • Are you currently plugged into the master socket or a slave socket?
Edited to correct "lower" to "higher". :doh:

1. Huawei HG612
2. MK4 with NTE5C
3. Master socket

I dont quite understand the correlation between a faulty power cable outside and an out of sync U1 band. Had there been a fault then surely it would've been on the copper back to the cabinet. Thoughts??
Logged

Ixel

  • Kitizen
  • ****
  • Posts: 1282
Re: Is this normal after switching ISP's???
« Reply #14 on: May 04, 2018, 03:31:24 PM »

Interesting, could you also post the bitloading and SNR per tone graph? I'm interested to see what's changed in U1. Electrical interference can cause problems with a DSL signal. Perhaps your phone wiring/phone line was managing to pick this up or perhaps the modem was getting it via the mains.
Logged
Pages: [1] 2
 

anything