Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: broadstairs on February 08, 2018, 03:55:57 PM

Title: Peculiar Errors on my Line with Varying SNRM
Post by: broadstairs on February 08, 2018, 03:55:57 PM
My line seems to be going downhill again with my SNRM being extremely jittery especially during the day. Upstream is the worst but downstream is not what I consider good. The problem usually starts some time in the morning mostly after 09:00 and usually improves after around 18:00. I am seeing quite a few errors on the upstream with a few on downstream. There is nothing in the house operating only at the times which correlates with the SNRM jitter. Also I don't notice noise etc on the landline (we don't use it much) but it does cause some jitter when it is in use.

The frustrating thing about this is that despite there  being an obvious problem with the line which could be some form of REIN I guess, TalkTalk take one look at my sync speed and say it is within spec and I don't have any disconnections so they wont do anything. I guess like a couple of years ago I'll have to wait until it gets really bad before anything is likely to get done.

Anyone have any idea as to why this might be happening?

Stuart
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: 22over7 on February 08, 2018, 05:45:33 PM
Broadstairs,

  To me, knowing next to nothing about broadband, the interesting about such phenomena is to try to understand them,
without presupposing they are important.

  If you use dslstats, it has a "bits" page, with a "botloading" subpage, where you can superimpose SNR per tone (under
"configuration > items to monitor > other".  In my case, there's quite some correspondence between droopy lines in
the SNR graph, and lower numbers of bits per tone.  It changes from time to time. I imagine the droopy bits, hence
under-preforming tones, correspond to sources of noise somewhere on my line to the PCP. Roughly speaking, the worst ones
(for me) occur smudged around tones 250, 1400, 3000 etc). These vaguely line up with with bitswaps per-tone, also on dslstats.

  Of course SNR and SNRM are different, and AFAIK SNRM varies per line, and even per U/D "band".  All these things vary
by time of day, how sunny it is, and whether or not it is the weekend.

  Anyway, there's a mass of baffling stuff going on, that stimulates the imagination, perhaps enough to read some of the
"tech" xdsl tutorials on this site, and really look at the Dslstats and MyDsalWebStats graphs. The more I read and look,
the less I feel inclined to fire off a complaint to my ISP.

  Mind you, I'd be very interested to read any comments you get from the kitties.
Title: Re: Peculiar rrors on my line with varying SNRM
Post by: ejs on February 08, 2018, 07:00:26 PM
I'll have to wait until it gets really bad before anything is likely to get done.

This happens due to the nature of xDSL technology, trying to get a high bandwidth over telephone wires which weren't really designed for such a task, and the price the service is sold at.

(Yes, I do realise that this probably wasn't the question you wanted answered.)
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: broadstairs on February 16, 2018, 01:56:44 PM
I am becoming more and more frustrated by the attitude of ISPs and in particular my ISP TalkTalk. I have been watching my line recently and have obviously got issues with it from an SNRM point of view. During the day time in particular the values are all over the place with some severe drops upstream and very variable downstream. However because my router manages to hold on to the connection TalkTalk say you are not having problems and you speed is within spec so basically go away. This in my view is a very shortsighted attitude as at some point this will cause a problem. Comparing my downstream now the that recorded by DSLStats last June shows a marked deterioration now but because it does not actually drop the simply refuse to even take a look. Nothing has changed in the house since last June in terms of electrical equipment and since the problem happens when nothing is in use it has to be external.

Stuart
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: skyeci on February 16, 2018, 02:29:55 PM
I hear you. I have had the same trouble with sky. 3 months of grief with ds snr loss and instability but much like yourself because my line was within speed specs (only just) they just wouldn't entertain looking at it.
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: ejs on February 16, 2018, 06:52:12 PM
I'm sorry but I really don't think the fundamental problem is with the attitude of ISPs. It's the nature of the technology. Yes it's rubbish but that's what you get for a cheap solution using the existing wires rather than spending lots of money to put in fibre optic cables in their place. Forget about looking at stats and trying to get something fixed before it might become an actual problem. Just ignore the stats, and if at some point it does become an actual problem, then you get it fixed. Or if they really can't fix it then you can cancel your service.
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: j0hn on February 16, 2018, 07:29:31 PM
There's nothing Talktalk can (or should imo) do about a varying snrm. That's why they don't give access to detailed stats. If you had no way to see the snrm you would assume everything is working perfect.
Really it is working perfect.
The snrm is supposed to be able to fluctuate. Yours is doing so more than the average line but it's working away.

Unless it starts causing the line to drop sync or creating so many errors you get packet loss, it works so why would they fix it.

You could report the jitter on the land line as that is a fault. Rectifying that may even solve the fluctuating snrm.
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: ejs on February 16, 2018, 07:46:27 PM
I assumed that using the landline is noticeable on the SNRM graph. I'm not sure if that's what you mean by the "jitter on the land line".
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: broadstairs on February 16, 2018, 08:26:55 PM
I think my point is that last June it was pretty damned perfect but now it's cr@p and at some point it WILL get worse and fail. So basically I have to wait to see the line fail and give me zero service before I can get it fixed.. I am aware that we have 18th century infrastructure for the 21st century however that is no excuse for a line which a while ago was pretty damned good. I am not complaining about speed but the fact that there is a problem with the line but no one is interested in fixing it.

Now I know I am ranting a little  ;) well maybe a lot  ;) but it does not alter the fact that my line is now cr@p but no one gives a sh1t. That does not make it right or acceptable. Back when we had G.INP I had a 70000kbps connection which was flawless but when they took it away since then it has been significantly under performing. If I had a 59999 kbps line which was performing very well I'd be at least satisfied. The fact that ISPs dont give access to true statistics is no acceptable.

Why should I have to wait until I have no service to complain and get it fixed?

Stuart

Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: burakkucat on February 16, 2018, 09:10:22 PM
I am aware that we have 18th century infrastructure . . .

One century too early.  ;)
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: ejs on February 16, 2018, 09:42:10 PM
Why should I have to wait until I have no service to complain and get it fixed?

Because everybody else does?

Everybody's line will eventually get worse and fail! Nothing lasts forever.

If you had the option, would you pay extra for a better level of service with one included health check / optimisation visit per year?
Title: Re: Peculiar Errors on my Line with Varying SNRM
Post by: broadstairs on February 16, 2018, 10:46:55 PM
If you had the option, would you pay extra for a better level of service with one included health check / optimisation visit per year?

Quite possibly as I already to on some things we have in the house. Actually those things are cheaper than my broadband  ;)

Stuart