Product: Vigor 130 ADSL/VDSL Modem

I'm on a long slow BT ADSL line at home that struggles to reach 0.6MBit speeds, and gives me a lot of reliability problems. However over the last few weeks i've hit a new problem i'm struggling to diagnose well enough that I can safely call BT in.

Symptoms:

The line will work ok for a while (where "a while" might be anywhere from 2 minutes up to 2 hours). During this time the Ping to (say) http://www.google.co.uk will be down around 20-30ms which is fine.

At some point the line will start to slow right down. The Ping will zoom up to anywhere from 1,300 to 3,900ms (!). Note these are on a quiet link (no big downloads running etc.)

Resetting the modem will fix things for a while, but then at some random time later the performance will collapse again.

A trace route shows the big delay is always in the first hop from my modem to the exchange.

I was using a Netgear DM200 modem and this problem was driving me nuts. I bought a new Draytek Vigor 130 to try to fix it, but although the issue happens less often with the Draytek, the modem still needs to be reset 3 or 4 times a day.

The Vigor has better line diagnostics than the Netgear, but while the performance collapse is happening the ADSL connect rate and error rate etc. stay pretty much the same. I can's see what's happening.

I'm wary of getting BT out yet again without being able to repeat the problem. If i'm unlucky and the line works ok for the 10 minutes the BT Engineer is on site I get stuck with a £200 bill.

Any ideas on how I might be able to characterise this fault so I have some chance of getting it fixed?

colin_e wrote: I'm wary of getting BT out yet again without being able to repeat the problem. If i'm unlucky and the line works ok for the 10 minutes the BT Engineer is on site I get stuck with a £200 bill.

Any ideas on how I might be able to characterise this fault so I have some chance of getting it fixed?

Record the ping times, using some free Network Monitoring software.

I'm a long time user of: https://www.paessler.com / but there's lots of other choices.

(Assuming the Vigor 130 is SNMP-capable, you can probably record lots of ADSL-related stats. as well)

I have my file server recording hourly ping stats, and these go back over several years.

I can tell you for example that at 10 pm yesterday the Min / Mean / Max pings to my UK ISP's web server were-

Code:

1368 / 3249 / 6182 (6 SECONDS worst case)

and at 3pm on the 16th of June (4 days ago) they were-

Code:

6647 / 7252 / 8804 (6 seconds BEST case!)

and these are far from the worst numbers i've seen.

However i've also had the experience of calling out a BT Engineer, watching them do a quick end to end IP test, say "it seems fine to me" and leave again within 15 minutes. If they don't happen to arrive at a time when the line is misbehaving that's it, no fix and a possible £200 bill. In my experience they don't take any notice of any performance data recorded by the customer, no matter how comprehensive.

You would think BT (aka OpenReach) woudl be able to leave some sort of line analyser or tracer on the line for a decent period, say a week, and look for problems like intermittent shorts or line noise, but that seems to be beyond them. I would really like to be able to determine myself what's happening before I roll the dice on a BT visit.

I used to have the same problem here. Line was perfect for months on end then suddenly unusable with pings through the roof.

BT were useless and would spend hours blaming the house wiring and never resolving the issue , this went on for 6 years until I changed to an LLU service.

The fault returned , I reported the stats to my ISP , the service provider checked and said there was a line problem.

2 days later I had 2 senior OpenReach engineers turn up, they looked at my set up and said there is nothing here that could cause an issue.

They plugged in a test device , kit that I have never seen before, in seconds they said there is a high resistance problem xx meters from here , that is the PCP ( green cabinet). A clue to the issue was the voice line was too quiet, slightly muffled but no hiss, pops, crackles. The fault is corroded joints in the PCP which causes intermittent problems.

They went off , changed the joints in the cabinet and the problem was gone. The engineer said , this should have been done years ago, the notes on your line show many calls for the same issue , they should have known how to cure this very common fault.

Thanks AdrianH54, that's very interesting. I've wondered if we might have to switch to a different ISP to get them to chase OpenReach, i'm curently using a small firm (Vispa) and they don;t seem to have much leverage, or interest to be honest.

colin_e wrote: Thanks AdrianH54, that's very interesting. I've wondered if we might have to switch to a different ISP to get them to chase OpenReach, i'm curently using a small firm (Vispa) and they don;t seem to have much leverage, or interest to be honest.

Andrews & Arnold have staff specially trained in giving OpenReach a hard time. As a friend of mine said to me when I told him I was switching over to A&A, "they look expensive - until something goes wrong"