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[aparat]

Hi I have been reading this forum for a while and I know there is a  lot of smart people in here.

I need advice if something is happening with my line because I notice drop on max attainable and SNR

I'm including before and after graphs and Plinks:

[NewtronStar]

Welcome to the forums aparat 

I am finding it hard to notice any big difference from both of those graphs you have posted the only thing that sticks out which is odd you seem to have less ADSl signal cutback on the after graph in D1 Band so your line should be performing better not worse , I can't see why a drop of max attainable and SNR could be effecting your line 

[aparat]

Hm... I also notice there is more FEC in 1 day now then it was in 11 days before

[Bald_Eagle1]

Reduced SNR, SNRM & Attainable rates are classic symptoms of increased crosstalk (or some other 'interference').

Even QLN looked better on 13th.

It may be interesting to see say 8 days of ongoing stats graphs back from the current time.

(Run GraphPD button in the GUI then enter 8 d for the period).

The resulting 8 day FULL__MONTY montage can be attached to a reply in this forum.

Alternatively, post a zipped copy of modem_stats.log somewhere for us to view/plot etc.

[aparat]

All I can do is take stats once a day at about 6pm for next 8 days. Dont have spare device to connect to modem LAN 2 and just leave it there. So Ill do it once daily. Will it be enough ?

[Bald_Eagle1]

If your router is close enough to the modem, you can connect a spare router port to the modem's LAN2 port & access the stats from any PC connected to the router, either via Ethernet or wirelessly.

Once daily stats are useful as a snapshot, but you will miss any often very important details regarding peaks/troughs in error counts etc. that would be visible from 24/7 logging.

[aparat]

Thanks guys for help and advise.

Hm.. I might be able to do it.

Do I have to change router IP to f.e. 192.168.1.2 and dhcp from 192.168.1.3 ? Do I have to change any settings in modem?

And how often hg612stats should collect stats.

[aparat]

Its ok now sorted. Ill log some stats for few days and reply in here.

[aparat]

I'm including stats from last 4 days cant do any more at the moment but it should be enough. At 24th Nov. 1730 there was power cut for 20 min so that's that reset

[burakkucat]

Its a pity that your computer and modem/router were not connected via a UPS so that they remained operational during the power outage because that may have clarified the extent of any crosstalk.

I'll try and attract an analytical Eagle to look at your latest graphs . . .

[kitz]

Not an eagle, but will a kitteh do in the meantime?

Your SNR for tones 500-800 has dropped a fair bit from the 13th -> 19th.
This corresponds with an increase to -110dB in the corresponding tones on your QLN.  Even D3 shows an increase from circa -130 to -120 dB.. This has resulted in less bitloading in those tone @ 500-800.

Your hlog remains practically the same and looks good, so your physical line seems fine.
 

I cant see anything glaring obvious from your full monty, but Im trying to look at them on an ipad.   Your original posted daily graphs seem the most telling.. and to me, everything appears to point to crosstalk.

Im assuming that with an original rate of 113,776 you were one of the first on your cab and because you are very close to the cab then you will be affected the most.  30Mbps seems a big hit to take all at once, but I think you'll find the biggest hits usually come first and continue as more people join the cab.

I wasnt first on my cab (25th) as I waited a few months due to other reasons.  By the time I joined the party I was at at practically exactly the same rate you are now.   Since then Ive lost circa 30Mbps.   Someone just a few of weeks ago knocked 5Mbps off in one fell swoop.. and I doubt crosstalk has finished with me yet :/

[aparat]

Thanks for reply 

That is right Kitz, with the rate of 132776 I was first ( OR guy told me it was first job on cab ) to have it done.
Hm.. that's right 30Mb hit is big, that's why I came here to ask someone smarter then me if it could be something else but it look like crosstalk

I live in high rise block of flats, and cab is like 200-300m from 9th floor to the cab. I checked because I just could not wait for it to come soon enough because my area wasn't in BT plans at all, BDUK FTW

I just hope that crosstalk wont bring it down below 80Mb ;/

[kitz]

Your distance is a wee bit shorter than mine then.

>> I just hope that crosstalk wont bring it down below 80Mb ;/

I know, I thought once upon a time that I had plenty to spare.  If I put a couple of lantiq based routers on that I have or the ECI modem, I'll  no longer sync at 80/20.  Im not sure about the HG612, it may just possibly scrape the 80/20 atm. My Zyxel is currently giving me about 84500, so one more hit like last week then its bye bye 80/20 for me

The sooner they bring out vectoring the better.  It cant come soon enough for many of us.

[Bald_Eagle1]

I'm including stats from last 4 days cant do any more at the moment but it should be enough. At 24th Nov. 1730 there was power cut for 20 min so that's that reset

A small downward, but distinct step in DS SNRM usually signifies an increase in crosstalk.
However, your step is only visible in US SNRM - DS is still steady.

The reduction in US SNRM could have been due to the power outage & resync being at around 18:00 (usually quite a 'noisy' time).
However, it hasn't recovered, which is slightly unusual.

Your error counts are generally quite low though (at the moment).


I was one of, if not the first to be connected to my FTTC cabinet back in June 2011.


An intermittent line fault developed after 1 month, which took 11 months to pinpoint to a corroded joint from the underground
cable to the pole mounted DP.

Once that was repaired, due to a distance of around 1100m from the cabinet, my connection was able to maintain around 30 Mbps sync speed for the next 7 months until I started seeing small stepped & sustained reductions in DS SNRM (from 6 dB to around 4 dB), always followed a few days later by a resync at a lower speed, with SNRM back to the target 6dB.

These DS SNRM reductions & resyncs have been confirmed as increased crosstalk as more users joined my cabinet.

Current DS sync speeds are around 21.6Mbps (fastpath), but they have been as low as around 19Mbps (interleaved) at times.

As more users join your cabinet, I would expect you will see similar reductions in DS SNRM, but you do have quite a bit of spare margin to play with before it starts to affect your max available 80/20 sync speeds.



FWIW, it might be worthwhile if you allowed the logging/graphing programs to update via the HG612 Stats logging GUI (the Receive beta updates option).
A little more detail is included in the snapshot & ongoing graph montages, such as average error counts per minute, hour, day etc.

[adslmax]

with the rate of 132776 I was first

I just hope that crosstalk wont bring it down below 80Mb ;/

Mine was the same last February first connected at 132,000K but now drop to 90,000K because SNR gone down from 21dB to 8dB