Connection Dropping

Hi folks,

For the last month now my connection has been dropping randomly day and night?

I have the following appearing in my router log:

Sep 22 23:58:39> DSL out of sync
Sep 22 23:58:51> DSL Carrier is down
Sep 22 23:59:26> DSL in Sync
Sep 22 23:59:31> DSL Carrier is up
Sep 22 23:59:31> sar read trained mode (1)(ADSL_G.dmt)
Sep 22 23:59:32> PPPD Terminated Through Signal
Sep 22 23:59:32> Connection terminated.
Sep 22 23:59:32> pingStat 2, oamHdr 230 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 200 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 280 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 240 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 260 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 600 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 230 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 800230 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 2B0 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 330 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 3B0 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 8002B0 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 800330 result 0
Sep 22 23:59:32> pingStat 2, oamHdr 8003B0 result 0
Sep 22 23:59:32> ppp0
Sep 22 23:59:32> closing 0.0.38.5
Sep 22 23:59:32> tn7sar_teardown_complete called for channel 0
Sep 22 23:59:32> ChannelTeardown returned rc = 0
Sep 22 23:59:32> pppd 2.4.1 started by root, uid 0
Sep 22 23:59:32> Connect: ppp0 {--}
Sep 22 23:59:36> ppp0
Sep 22 23:59:37> PPPoA Connect with IP Address 212.159.22.223
Sep 22 23:59:37> PPPoA Connection Successfully Established

I have raised a fault the PN web site but wondered if anyone here could shed any light? Its happening more and more these days - at least 10 times tonight between 7:30pm and midnight.

I have a d-link dsl524t router if that helps.

Thanks in advance for any help on this one.

Max

This may also help??

Modulation ADSL_G.dmt
Annex Mode ANNEX_A
Max Tx Power -38 dBm/Hz

Item Downstream Upstream Unit
SNR Margin 4 21 dB
Line Attenuation 43 27 dB
Data Rate 4512 448 kbps

I am afraid I cannot help you much directly, however I am seeing very similar things, also at similar times of day, mostly concentrated in the evenings, which is quite interesting. Plusnet have mostly so far just given me the usual stuff about removing other phone equipment (all of which I have done) and they don't seem to be getting far in terms of giving me a real explanation.

Initially they blamed MAX DSL (quite sensibly, I guess) but as it has probably been at least 12 days since they activated that on my line they have gone quiet on that front now.

I too would be grateful for any hints, even if they seem obvious - there may be something stupid I've overlooked. I've got the latest firmware (on my ZyXEL P660R) ... the only possible issue is that I don't in the strictest sense of the word have a BT "master socket" - where the wire comes into the house from the road there is just a blanking plate and a cable running off to a socket in the lounge (about a 5 metre cable) so I wonder if that is causing problems.

It may not be acceptable for your needs, but after having months of random disconnections I got BT to run a line test due to a lot of noise on my line they found a fault and took a few hours to clear it.This did not not stop the disconnections so in the end I bit the bullet and had my SNR/margin threshold increased and interleaving turned on.The SNR threshold increase lost me a bit of speed..... I went from a router report of a downstream rate of 8128Kbps at a SNR/margin of 6db or less (it got down to 1db at one stage) to the figures listed below as stability is more important to me than speed.

DSL Status : Up
DSL Modulation Mode : GDMT
DSL Path Mode : INTERLEAVED
Downstream Rate : 6976 Kbps
Upstream Rate : 832 Kbps
Downstream Margin : 13 db
Upstream Margin : 12 db

I thought I would notice a severe drop in speed but funny enough I seem to be getting better downstream rates than when I was apparently synced at 8128Kbps

here is a Plusnet speed test from this evening

24-09-2006 22:43:24 5424

and to double check that I did an ADSL Guide one shortly after

Downstream 5,181.9 Kbps( = 5.1 Mbps )
Upstream 687.4 Kbps ( = 0.7 Mbps )

Just to put things into perspective and to show that I have not really lost that much here is a sample of my speeds taken at on various days and at varous times before I had the interleaving turned on and the SNR threshold increased.That was always assuming the connection would stay up long enogh to them.

12-09-2006 17:22:48 3934
12-09-2006 15:30:52 4015
12-09-2006 12:23:19 3990.9
12-09-2006 05:18:02 6258.2
11-09-2006 19:40:16 3511.4
11-09-2006 17:20:34 1451.7
10-09-2006 22:23:56 846.2
10-09-2006 22:23:32 679.6
10-09-2006 20:13:47 5145.7

So in my opinion I have not lost an awful lot...... but for me the improtant thing is that my connection has not dropped in 5 days and has been rock solid.Have had minor fluctuations in the SNR but at 13db they don't cause as much havoc as when my SNR was 6db on 8128Kbps.

Like I said in the beginning my method may not suit your needs...... but hope it has given you something to consider.

It would appear that somebody (probably a previous occupant) had moved your "Master" socket from the cable head and extended it to the Lounge.

What you should have is an NTE5 Master socket at the cable head where you say you have a blanking plate and your extension to the Lounge should be connected to the faceplate terminals. If you are hearing noise on your voice line, you should persist with BT to send an Engineer out. If you point out the blanking plate to the Engineer, he will almost certainly fit an NTE5 socket because this allows BT to conduct their tests at the cable head and defer any problems with your extension wiring to you.

Once BT have fitted the NTE5, you will need to either a) change the Lounge faceplate for an extension faceplate or .... b) cut off the Ring Capacitor, Resistor and surge suppressor on the extension socket. I would also disconnect the wires from pins 3 & 4 on the NTE5 feeding the extension socket.

thanks for the reply wheelnut.

yeah, we've just moved in to this house. The BT engineer who installed our line said the wiring was a right mess, I think they had an NTL line but using some BT cabling, and all sorts of [censored]! And having fitted some new light fittings myself, the electrical wiring wasn't any better.

The socket in the lounge is indeed an NTE5 master socket. I am tempted to pull out the cable feeding that from the face plate, which currently looks like some horrible old alarm style (lots of colours rather than white/colour pairs) cable, and replace it with some CAT5. However I gather that would be illegal so I won't be doing that. *cough*

Do you think if I phone BT and explain that the cable doesn't give me satisfactory ADSL performance they would either replace the cable or (more likely) just relocate the master for me? My main concern is that it would take them a few weeks to get an engineer appointment. The faceplate is literally inside the front door, not a practical place for my router, so if they put the master there, and I ran an extension from that to where my router is, using decent CAT5 cable, is that likely to give satisfactory ADSL performance? The engineer said normally they would put the master there the cable comes in, but because there was already a cable running from there to the lounge, and the face plate just inside the front door is an inconvenient place, he would just use the existing cable.

Thanks for all the advice here - I'm new to all this ADSL troubleshooting since I've been using ADSL for a few years without any problems. Apologies if I'm on the wrong group for this sort of stuff.

cheers
-ben

Ian, thanks for the reply...

Sorry to be a muppet, but how do I have my SNR margin increased? I think from my router interface, I already have interleaving turned on

plutonium> wan adsl chandata
DSL standard: ADSL_G.dmt
near-end interleaved channel bit rate: 5088 kbps
near-end fast channel bit rate: 0 kbps
far-end interleaved channel bit rate: 448 kbps
far-end fast channel bit rate: 0 kbps

plutonium> wan adsl linedata near

noise margin downstream: 14 db
....

I guess noise margin is just another term for SNR margin, depending what the router manufacturer decides to call it? That noise margin looks ok now, BUT when I did it late last night, it was much lower, about 5 I think. I have read about problems where the connection can be much worse at night, due to stronger AM radio signals causing interference, possible interference from street lights, and even dimmer switches in neighbours houses possibly causing problems! I think at least one of these is probably contributing to my problems.

thanks again
-ben

Hi Ben,

This is probably going a bit off topic but the discussion may be relevant to the OP......

I would advise against trying to get BT to fix an ADSL performance problem which is related to your own wiring. Even if they do come out, they will charge you for the work.

A better course would be to tell them that you are having Voice quality problems and believe it to be related to the non-standard wiring from the incoming cable head to the Lounge socket which was installed (possibly by the previous occupant) before you took occupancy. Note that it is ilegal to tamper with the wiring to the backplate of the NTE5 Socket.

BT installed a lot of Aluminium cable in the 60's and 70's and there are known problems with terminations between Aluminium and Copper. BT have recently changed the crimps they use for these terminations and the technicians have to replace any of the old ones if they see them.

I would advise you to let BT put the NTE5 socket back at the front door position. They will do this for free because it then only requires them to test their cabling to the Test Socket behind the faceplate. You can then replace the extension wiring and fit your own extension socket in the Lounge. This will also let you test the SNR and attenuation at the cable head.

R

"That noise margin looks ok now, BUT when I did it late last night, it was much lower, about 5 I think"

I would think that based on what you have said here, that it is something on the outside drastically affecting it.As 14db is I would have thought been ample...... my problem was I started off with 6db so it did not take much to lower that.

I think I personally would tend to go along with the poster that suggested telling BT you are having troubles with the voice side of things and see what happens.

I wish you luck these sort of problems are very tricky and frustrating trying to nail them down

BT want to charge me 100+ quid to relocate the master socket, which I am not happy about. They say the engineer would have asked me where I wanted the master socket when he came (which he did, to be fair) but I don't think that really excuses him re-using someone elses sloppy wiring and then charing ME to put it right. I have booked an appointment for 3 weeks from now anyway (standard BT waiting time in my experience) and will cancel it if I come up with any ideas before then.

thanks for all the advice from everyone so far.

I've had poor SNR ever since the move to MaxDSL - consistently 6-7 at best, sometimes down to 4 or less!
The line speed is generally pretty variable - max sync is around 3.4Mbps and true throughput can be anything from 350Kbps to 1.2Mbps.

I've seen people mention increasing the SNR threshold as something that may help - how did you go about doing this? Incidentally, I'm already showing as having interleaving on.

Cheers

"I've seen people mention increasing the SNR threshold as something that may help - how did you go about doing this?"

After weighing up my options I basically just sent in a question/ticket requesting it as one of the prefered options,As I had asked if BT could fix my sync rate lower.The answer I recieved to that question/ticket was as follows

Dear Mr ******
In response to your queries.

a) We cannot request BT to reduce the level at which you are syncing at, although we can request for the target noise margin to be raised, which generally equates to 800kbps sync speed per 3dB noise margin.

So I sent a response requesting that they arrange that,which they have done.That being preferable to my final option which was...... from the same reply from CS

b) We can also instigate an order from Max to fixed rate.

I had previously been through Plusnets tests which proved inconclusive....... so if it something you can request without having the tests done is something I don't know:although I cannot see any reason why it could not be done.

So it seems you just have to ask :-)

Thanks Ian, I have sent a similar request to plusnet, and will see what they say. If I get a stable but slower connection, that's considerably preferable to paying BT 100+ quid for 5 minutes work. ;-)

Let me know how it goes..... all the best

Cheers Ian - Thanks for the info

I think I'll put in a ticket with a request for this, as my broadband has been a pretty variable experience since the MaxDSL upgrade - I'm not close to my exchange and I believe my line is moderate to poor (though voice does not seem to be affected).

I think it's worth sacrificing speed for stability, even if it means going to fixed (but let's hope that's not necessary).

Edited by PandR (Tue 26-Sep-06 14:55:48)