Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: roseway on August 20, 2015, 07:26:59 AM

Title: Abrupt drop in SNRM
Post by: roseway on August 20, 2015, 07:26:59 AM
Look what happened yesterday. There were Openreach vans in our road, including one parked for a couple of hours in a neighbour's drive. Later in the evening...

I presume this is crosstalk, although the timing is a bit odd. My connection didn't resync, it just lost about 2 dB SNRM on both upstream and downstream, and this has had a big impact on my max attainable speeds (I've lost about 9 Mbps on the downstream attainable).
Title: Re: Abrupt drop in SNRM
Post by: peterj on August 20, 2015, 07:41:19 AM
I had a similar abrupt drop in May. Sync went down from 47 to 39 in one go and other than a bit of a gain moving to G.Inp it never recovered. If it is cross talk I imagine you will suffer a similar speed loss when your line next resyncs  :(
Title: Re: Abrupt drop in SNRM
Post by: tbailey2 on August 20, 2015, 08:14:37 AM
Look what happened yesterday. There were Openreach vans in our road, including one parked for a couple of hours in a neighbour's drive. Later in the evening...

I presume this is crosstalk, although the timing is a bit odd. My connection didn't resync, it just lost about 2 dB SNRM on both upstream and downstream, and this has had a big impact on my max attainable speeds (I've lost about 9 Mbps on the downstream attainable).

Matter of interest, what is your actual d/l speed currently vs attainable? Looks same as what happened to me and many others when a neighbour gets fibre.... Your FECs are quite a lot higher since so there is certainly extra noise around...

Attached is an MDWS comparison of your Bits/Tone as it is now (at top) and as it was couple of hours before the 'happening'...
Title: Re: Abrupt drop in SNRM
Post by: roseway on August 20, 2015, 10:00:13 AM
These are my current attainable and actual speeds:

Code: [Select]
Max: Upstream rate = 25467 Kbps, Downstream rate = 68220 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 77421 Kbps
Title: Re: Abrupt drop in SNRM
Post by: tbailey2 on August 20, 2015, 11:57:03 AM
Yes, that's there originally - but I just wondered what is your ACTUAL download speed via a speedtest vs what it says it is....
Title: Re: Abrupt drop in SNRM
Post by: roseway on August 20, 2015, 12:54:06 PM
The actual connection speed is given above. Speedtests vary of course and tell you more about routing conditions and the quality of the test server than the state of the connection. But if you want some examples:,

speedof.me
Downstream: 77.61 Mbps
Upstream: 17.68 Mbps

speedtest.net
Downstream: 70.44 Mbps
Upstream: 17.11 Mbps
Title: Re: Abrupt drop in SNRM
Post by: les-70 on August 20, 2015, 04:29:04 PM
   That almost exactly what next door does to me.  I confirm that it is shock when you first see this!
Title: Re: Abrupt drop in SNRM
Post by: NewtronStar on August 20, 2015, 04:52:21 PM
All you can do is try and hang onto current sync rate with an Snrm of 3.8dB yet don't see any error's coming from the downstream if this is crosstalk but it does looks like it.
Title: Re: Abrupt drop in SNRM
Post by: garypower on August 21, 2015, 03:01:21 PM
Crosstalk is a killer - graph shows the difference for a week when my next door neighbour went on holiday... shame is they came back a week later!

vectoring can not come quick enough!
Title: Re: Abrupt drop in SNRM
Post by: Chrysalis on August 21, 2015, 06:34:29 PM
sudden drops I reckon most likely cause is crosstalk aka new line turned on.

The time of day is a bit late but given its summer and you seen the vans, it would all fit.

I remember when sky installed my dish at 10pm one night.  They did come abit earlier but was a power cut so came back late to finish it off.
Title: Re: Abrupt drop in SNRM
Post by: kitz on August 21, 2015, 08:45:17 PM
Unfortunately it does look remarkably like crosstalk.   I found that the early ones took the most away, but there still the odd one or two that are at about 5Mb from last year.

Like you say though the timing is strange.  I wonder if they perhaps didnt turn on their router until later at night.   

There's one way that you can check if it is cross-talk and thats ask them to turn their router off and back on again and you will get the shape just like on garypowers graph.   I saw similar when the people across the road when on holiday. 

Also expect to see blips like this when they reboot their modem.
Title: Re: Abrupt drop in SNRM
Post by: roseway on August 21, 2015, 11:02:52 PM
Unfortunately I don't know these particular people well enough to ask favours of them, but thanks for the suggestion. :)
Title: Re: Abrupt drop in SNRM
Post by: AArdvark on August 21, 2015, 11:20:39 PM
@roseway

A perfect opportunity to introduce yourself !  ;D

Nip over with a bottle of wine and a set of screwdrivers !  :D :D ;)

I am sure they won't mind.  ::)
Title: Re: Abrupt drop in SNRM
Post by: roseway on August 22, 2015, 06:43:51 AM
:)
Title: Re: Abrupt drop in SNRM
Post by: Bald_Eagle1 on August 22, 2015, 08:20:04 AM
Crosstalk is a killer - graph shows the difference for a week when my next door neighbour went on holiday... shame is they came back a week later!

vectoring can not come quick enough!

I see you got a nice increase in sync speed during that 'golden' period, but SNRM is quite low now, so I suspect it won't be too long before 'normal' sync speed resumes (Unless G.INP now allows it to hang on at 60Mbps as your DS error counts are generally pretty low).

Title: Re: Abrupt drop in SNRM
Post by: Chrysalis on August 22, 2015, 08:55:39 AM
I think knocking on doors and asking someone to turn off their broadband is a bit weird socially, myself. :)
Title: Re: Abrupt drop in SNRM
Post by: AArdvark on August 22, 2015, 02:59:38 PM
I think knocking on doors and asking someone to turn off their broadband is a bit weird socially, myself. :)

 :D :D
That is why I said take a bottle of wine !
You introduce yourself, open the wine as you step through the door.
Then with nice generous gestures accidentally 'spill' the wine near the modem.
While you are apologising/mopping up the wine you disconnect the modem.
Done !

Sorry, was that not clear !?  ::) ;)  :lol:

P.S. It would be white wine of course.  ;D
Title: Re: Abrupt drop in SNRM
Post by: roseway on August 22, 2015, 03:51:17 PM
Thank you for the suggestion, but I want to keep on good terms with my neighbours. ;D
Title: Re: Abrupt drop in SNRM
Post by: kitz on August 22, 2015, 03:56:30 PM
 ;D
Title: Re: Abrupt drop in SNRM
Post by: tommy45 on August 22, 2015, 04:21:38 PM
;D
then don a balaclava some sharp side cutters and a pen light and in the wee small hrs  cut their phone line, with any luck you will get several days before their modem will be able to sync :fingers:
Title: Re: Abrupt drop in SNRM
Post by: AArdvark on August 22, 2015, 05:49:03 PM
Hmmm ..... just possibly might have veered the wrong side of accidental  ::) :D

You do realise that to avoid suspicion you would have to cut your own line as well !  ;D

Not too sure how far that one flies though as it MIGHT have some impact on your own ability to use your broadband.  ::)  :D
Title: Re: Abrupt drop in SNRM
Post by: NewtronStar on November 05, 2015, 05:47:33 PM
Just a wee look at Roseways stats this looks odd the attainable is 52760 kbps and the sync rate is 70932 kbps that is 18 megs of a difference is your attainable being displayed correctly ?
Title: Re: Abrupt drop in SNRM
Post by: roseway on November 05, 2015, 06:47:47 PM
Strangely that is what the modem is reporting:

Code: [Select]
Max: Upstream rate = 25475 Kbps, Downstream rate = 52528 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 70932 Kbps

The SNRM is close to nominal, so I guess that it's an error in the modem firmware (HG612).
Title: Re: Abrupt drop in SNRM
Post by: NewtronStar on November 05, 2015, 07:24:04 PM
The SNRM is close to nominal, so I guess that it's an error in the modem firmware (HG612).

I see the SNRM has gone up since your last resync and crosstalk has taken effect with a loss of 7megs  >:( but can't remember your stats before the resync as the SNRM history is hidden or removed  ;)
Title: Re: Abrupt drop in SNRM
Post by: Chrysalis on November 05, 2015, 08:31:09 PM
roseway had max 80meg sync at start,
Title: Re: Abrupt drop in SNRM
Post by: tbailey2 on November 05, 2015, 09:10:23 PM
The SNRM is close to nominal, so I guess that it's an error in the modem firmware (HG612).

I see the SNRM has gone up since your last resync and crosstalk has taken effect with a loss of 7megs  >:( but can't remember your stats before the resync as the SNRM history is hidden or removed  ;)

There's no data missing or removed except for a couple of weeks back. Eric had 80/20 or close for ages...
Title: Re: Abrupt drop in SNRM
Post by: NewtronStar on November 05, 2015, 09:19:09 PM
There's no data missing or removed except for a couple of weeks back. Eric had 80/20 or close for ages...

If I look at roseways SNRM graph for two days it's fine if i go above three days it says waiting

Title: Re: Abrupt drop in SNRM
Post by: tbailey2 on November 05, 2015, 09:29:52 PM
no problem here...
NB: you can get the sync figures at the time of any resync by hovering over the entries in the dropdown list at top right of the graph
Title: Re: Abrupt drop in SNRM
Post by: NewtronStar on November 05, 2015, 09:45:21 PM
no problem here...
NB: you can get the sync figures at the time of any resync by hovering over the entries in the dropdown list at top right of the graph

It's not working for me all the other stats are available we should probably take this issue to http://forum.kitz.co.uk/index.php/topic,14361.945.html (http://forum.kitz.co.uk/index.php/topic,14361.945.html)
Title: Re: Abrupt drop in SNRM
Post by: tbailey2 on November 05, 2015, 09:47:21 PM
no problem here...
NB: you can get the sync figures at the time of any resync by hovering over the entries in the dropdown list at top right of the graph

It's not working for me all the other stats are available we should probably take this issue to http://forum.kitz.co.uk/index.php/topic,14361.945.html (http://forum.kitz.co.uk/index.php/topic,14361.945.html)

You appear to be using Chrome whereas I was using FireFox but just tested Chrome and that's okay at any period as well. But I've never tried it on an old OS like Vista
Title: Re: Abrupt drop in SNRM
Post by: NewtronStar on November 05, 2015, 10:00:52 PM
no problem here...
NB: you can get the sync figures at the time of any resync by hovering over the entries in the dropdown list at top right of the graph

It's not working for me all the other stats are available we should probably take this issue to http://forum.kitz.co.uk/index.php/topic,14361.945.html (http://forum.kitz.co.uk/index.php/topic,14361.945.html)

You appear to be using Chrome whereas I was using FireFox but just tested Chrome and that's okay at any period as well. But I've never tried it on an old OS like Vista

I'll try it out on Win8.1 in 3 minutes the username & password needs to re entered never got around to doing that just to lazy.
Title: Re: Abrupt drop in SNRM
Post by: NewtronStar on November 05, 2015, 10:08:18 PM
I am using Windows 8.1 and IE11 and same result roseways SNRM history will not go above 2 days the MDWS window just says waiting.
Title: Re: Abrupt drop in SNRM
Post by: tbailey2 on November 05, 2015, 10:35:15 PM
I am using Windows 8.1 and IE11 and same result roseways SNRM history will not go above 2 days the MDWS window just says waiting.


Same combo is fine here. Is it just roseway then and just SNRM? If so then I have no real idea at the moment...

Edit: this is now fixed.... see here (http://forum.kitz.co.uk/index.php/topic,14361.msg304174.html#msg304174)
Title: Re: Abrupt drop in SNRM
Post by: roseway on November 05, 2015, 10:51:19 PM
To satisfy your curiosity about my recent history, prior to the last resync nearly three days ago I had an unbroken uptime of about 76 days. Early on in that period my SNRM dropped by about 2 dB (a new crosstalk disturber presumably), and it stayed at just below 4 dB for the remainder of the uptime. Not suprisingly, when the connection finally dropped three days ago it reconnected at a lower speed.
Title: Re: Abrupt drop in SNRM
Post by: ktz392837 on November 06, 2015, 11:48:22 AM


it stayed at just below 4 dB for the remainder of the uptime. Not suprisingly, when the connection finally dropped three days ago it reconnected at a lower speed.

It is a pity you can't control target db.  My line hunged on at 2db for weeks until I needed to resync.  I am sure a 3db option would make sense.
Title: Re: Abrupt drop in SNRM
Post by: arronlowley on November 07, 2015, 12:29:42 PM
i lost 15mbps attainable rate because someone joined in my area, then yesterday my router reset and gave me 80 with a max attainable of 71 and made my downstream snr 3 o.O, i reset my modem like a tit and now im back to 71 -_-
Title: Re: Abrupt drop in SNRM
Post by: Chrysalis on November 08, 2015, 12:47:17 AM
I would have watched the ES for a bit, and then make the decision, staying at 3.0 snrm could have been wrong also if the ES were too high. So dont worry over it too much :)