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[YNWA]

Hello,

I do not live in the UK, since I am unable to get help locally, perhaps someone can point me in the right direction.

For the past month or so, I've been having some serious ADSL issues. Please take a look at my line stats (posted below). Pay special attention to the items boxed in RED. These screenshots were taken within 5 minutes of ADSL sync-up... I've had this service (2048/512) for over a year and have experienced NO PROBLEMS whatsoever. Steps I've taken so far:

1. Connect using 4 different ADSL modems
2. Re-wired my house

I also requested a line test from the local Telco (result: no issues). Contacted my ISP, only to have them inform me that everything is "fine" on their end...  It's pretty obvious (as per screenshot) there IS a problem, I just don't know where.

As you can see, the high number of CRC/HEC errors (not to mention OCD / SEF / LOS) being reported in the first 5 minutes of 'showtime' is giving me big problems. With these errors, I cannot maintain sync for more than 5 minutes. My (downstream) SNR also fluctuates wildly. It should be noted however, I do not have any problems maintaining sync late at night -- say from midnight to 6 A.M.

Any other suggestions?

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[roseway]

Hi and welcome

Two things come to mind:

1. Although you have rewired your house, is it possible for you to test the connection with all extension wiring disconnected, just to make certain that there isn't an internal wiring fault?

2. The most likely thing (I think) is electrical impulse interference, which could be caused by any faulty or badly designed equipment. You may find this page helps you to find the source.

[YNWA]

@roseway, thanks for replying

Two things come to mind:

1. Although you have rewired your house, is it possible for you to test the connection with all extension wiring disconnected, just to make certain that there isn't an internal wiring fault?

Yes -- although I seriously doubt it's an internal wiring fault. I will give it a try nevertheless.

2. The most likely thing (I think) is electrical impulse interference, which could be caused by any faulty or badly designed equipment. You may find this page helps you to find the source.

REIN -- it's very possible... Actually, I came across the page while googling a couple nights ago... Are there any other methods to test for REIN without an AM radio?

Something worthy of mention...

Last month, some new neighbors moved in and made renovations to the property next door. I don't know what was done exactly, but it was quite extensive. My connectivity issues started right around that time. From what I can tell, new electrical appliances were also installed on the property. I've long suspected this to be the problem, however, I am unable to confirm this.

Assuming my suspicions are correct, what can be done about it?

Also, could a fault at the DSLAM be attributed to errors I see in the router stats?

[waltergmw]

Hi YNWA,

Will your router(s) support Routerstats and DMT to produce some pictures such as those here:-

http://forum.kitz.co.uk/index.php?topic=4399.0

Kind regards,
Walter

[kitz]

As has been already mentioned - I suspect REIN is the most likely cause... but unfortunately it is sometimes hard to track down the culprit.

With you being on a longish line (53dB) then the line will be more susceptible to any EMI that occurs, your SNR Margin though in the 2nd capture is quite high and that should more than suffice for normal background type EMI.

As walter suggests - see if you can get routerstats to work with your router and get it to plot your SNRM..  it may well show a pattern which could help identify something being switched on./off.


Ummm - I just noticed in the 4th set of stats your attenuation figure has changed to 45dB.  Attenuation should be a more or less static figure since its related to the length of your line.   Its also strange that the sync is worse when the atten is lower. 
Changes in attenuation is normally indicative of faulty internal wiring/faulty filters or a line fault,

[YNWA]

Hi YNWA,

Will your router(s) support Routerstats and DMT to produce some pictures such as those here:-

http://forum.kitz.co.uk/index.php?topic=4399.0

Kind regards,
Walter

I cannot get Routerstats nor DMT to work. It seems my modem/router (Xavi X8824) is not supported. 

Ummm - I just noticed in the 4th set of stats your attenuation figure has changed to 45dB.  Attenuation should be a more or less static figure since its related to the length of your line.   Its also strange that the sync is worse when the atten is lower. 
Changes in attenuation is normally indicative of faulty internal wiring/faulty filters or a line fault,

You're absolutely right -- Line Attentuation should be consistent, not fluctuate each and everytime a connection is established... I'm narrowing it down to two things: (a) REIN; (b) faulty wiring.

Since this is an older home, it has no NID but a protector block where a black (heavy gauge) drop wire runs from the telephone pole outside to the block itself. Interestingly, while making a call on my home phone yesterday, I heard static. It was a little windy outside, although nothing out of the ordinary. As soon as the winds stop, so did the static... I read somewhere that this (untwisted) black drop wire can cause a lot of problems for DSL. I may be an expert in computers, but I'm no phone or telco expert... What should I do to remedy this?

Also, when I did the re-wiring I did not use CAT5 since I had spare phone wiring (of the old quad type RGYB) lying around. Before re-wiring, it took forever for the modem to sync-up; however, with the new wiring in place, sync-up now takes less than 30 seconds. Connectivity issues still persist, however.

I'd like to use the Yellow/Black pair for DSL and have Red/Green for the phone, but the protector block only allows a single line to be connected. As it stands now, the phone AND dsl are using the red/green pair with a ADSL splitter separating the two. Unless I can replace the protector block with a new one (or better yet, a real NID), I'm stuck in a rut.

Your thoughts?

[waltergmw]

Hi YNWA,

If this is going to be a long battle with your provider it might be worth buying a router that is at least supported by routerstats lite.

Wind-crackling and variable attenuation does seem to suggest an external wiring fault which will cause mayhem on DSL.

I'm not familiar with your cabling as it's not UK, but you should ensure you are al least using twisted pairs.
Years ago we used to have a 4 wire single twisted cable and that is a disaster in noisy environments.
The only trick I learnt with that was to use "opposite" pairs and not adjacent ones.
If REIN is still suspected I'd try to get some FTP earthed at one end only.

Kind regards,
Walter

[YNWA]

Hi YNWA,

If this is going to be a long battle with your provider it might be worth buying a router that is at least supported by routerstats lite.

Wind-crackling and variable attenuation does seem to suggest an external wiring fault which will cause mayhem on DSL.

Routerstats-LITE is what I tried since it had the 'user-define' option. It was able to connect, but then it errored out... I don't remember the exact wording, but it said my device wasn't supported... While on the subject of routers, I did have a Zyxel P660 (which I believe is supported by DMT), but it died on me six months ago. Since then I've been wanting to get a new one -- I just haven't got around to buying one yet...

By external wiring fault, do you mean the black (heavy gauge) drop wire coming into the property or the actual cabling from the DSLAM?

I'm not familiar with your cabling as it's not UK, but you should ensure you are al least using twisted pairs.
Years ago we used to have a 4 wire single twisted cable and that is a disaster in noisy environments.
The only trick I learnt with that was to use "opposite" pairs and not adjacent ones.
If REIN is still suspected I'd try to get some FTP earthed at one end only.

The type of wiring that's currently being used is the "old telephone wire" as shown here. After reading numerous articles on the subject of DSL and home phone wiring, I'll definitely be re-wiring with CAT5. You mentioned using "opposite" pairs not ajacent ones -- can you elaborate on this? The current phone wire from the protector block to the master socket has 4 wires (2 pair); red/green (line1) and yellow/black (line2). The former is being used, not the latter. I've thought about swapping the pairs, but don't think it'll make much difference.

[waltergmw]

Hi YNWA,

I was talking of the drop wire. Since presumably there are a number of ADSL users off the main cable to the exchange, most of them aren't complaining ?

The picture is difficult to see clearly but the cable is probably similar to the one I'm talking about. That cable had four cores bunched together and twisted as a single group of four wires as opposed to twisted pairs.

I found that if you are forced to use such cabling, and going round the cores in order 1,2,3,4, you should use 1 and 3 as one pair and 2 and 4 as the other.

I would be surprised if your telco wasn't responsible for the external wiring from your house to the pole (or underground cable) to the street cabinet and thence to the exchange. If so try to raise a fault call with them to fix the crackiling phone. Once that is done then review the result and proceed. In general terms I would mount the modem as close as possible to the entry point into your house and then run ethernet or home plugs to distribute your home network as you need. For an example of home plugs see:-

http://www.netgear.com/Products/PowerlineNetworking/PowerlineEthernetAdapters.aspx?for=Home+Networking

but do be careful to choose the versions that match your mains wiring.

Kind regards,
Walter

[kitz]

You're absolutely right -- Line Attentuation should be consistent, not fluctuate each and everytime a connection is established... I'm narrowing it down to two things: (a) REIN; (b) faulty wiring.

More likely faulty wiring or a line fault - deterioation of the physical line.

REIN usually affects the SNR not the attenuation.

It was a little windy outside, although nothing out of the ordinary. As soon as the winds stop, so did the static...

Could be something like the line brushing up against a tree in the wind.  This 'rubbing' can cause the wire to become exposed/damaged and could well account for your symptoms.

Routerstats-LITE is what I tried since it had the 'user-define' option.

Ive managed to get several unsupported routers working with the full version of routerstats, it is a bit of messing around, but can sometimes be done with a bit of patience and marking the html.  I really dont know about the Xavi X8824 though since its not a router that is common in the UK.

[YNWA]

This is getting ridiculous to the point where I'm unable to use the internet without experiencing loss of signal and/or dropout every 5-10 minutes. My situation seems to be getting worse as the days go by. I cannot get the modem to sync anywhere near 2 Mbit speed (as it used to), instead downstream ranges from 128Kbps to 512Kbps with SNR of 5.5db!! The lowest downstream rate I've seen is 32kbps! No, this isn't a joke -- this is for real. Hell, I can get better speeds with 56K dialup! The only time I could even achieve 1Mbit or 1.5Mbit speeds is during the wee hours of the morning; even then, there's no guarantee.

I'm totally convinced there's an external fault on the line. Either that or there's some sort of short somewhere on the line. Can REIN be at fault here? Maybe, although I don't think REIN can have such a big impact or could it? A technician will be coming over this week to check for problems.

P.S. - While typing this, my downstream is at 736Kbps... After 15 minutes AND three dropouts, currently connected at a pathetic 320/512. 

[roseway]

It does look like a line fault, particularly in view of what you said about the effect of the wind. Hopefully the technician will find the cause.

[kitz]

As previously mentioned the fluctuation of your attenuation would point to a fault on the physical line.

If you were in the UK, I would suggest you do did something called the "Quiet Line Test", which is a special number used by BT for checking the voice part of the line for noise.
If you can hear noise on the line for voice, then this certainly a problem with the telephone cable.  Im not sure if your country has such a facility.

If there is noise on the voice part of the line, we would then suggest you call out and engineer from your Telephone Company - not your adsl provider.  Problems that affect the voice side can and will also affect your adsl, but because its also affecting voice it needs fixing by the telephone company engineers.
If you are hearing noise on the voice side too.. then its likely deterioration of the physical cable some point before it gets to your home.  It could be water on the line, a worn cable or a rusty joint.

Good luck with the technician and hope he finds the fault.

[YNWA]

Thanks for your replies and suggestions

Talking about 'noise', there was a lot of static on the phone today. However, it came as no surprise since it was quite windy this afternoon.

Just to give you an idea of how bad things really are, here's another screenshot. With an uptime of only 10 minutes, this has got to be the worst stats I have ever seen. I've contacted the local Telco (for the umpteenth time), they will be sending a technician to my residence this week. Anxious to see how it turns out... I'll post the results.

I'm beginning to wish I was in Europe or the U.S. It's rather difficult trying to get things done around here.



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[kitz]

>> SNRM -2 dB

Your router is hanging on to your connection by the skin of its teeth - No wonder you are getting lots of CRC/HEC errors after only 10 mins.

>> there was a lot of static on the phone today. However, it came as no surprise since it was quite windy this afternoon

I wouldnt be too surprised then if it is a worn cable.  May be worth having a look at the wires outside your home and check their condition.  Also make sure that its not rubbing up against tree branches or similar.

>> It's rather difficult trying to get things done around here.

It can be the same in the UK.  Depends on who your ISP/Telco is.  Some are much more co-operative than others.