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Gar
22-05-2011, 21:59
For the past few days, my internet connection has been randomly dropping. It can occur once every ten minutes for a short while, and then it can be okay for hours. Sometimes it will drop once, then be okay for several hours, then drop again, then be okay for another several hours. There doesn't seem to be a pattern (at least not that i can tell).

However, during these drops, my modem lights remain normal. There is no flickering of lights, no reset, etc. It's as if the modem is still holding a connection.

When the connection drops, it comes back on it's own after a minute or two. Or, if I reset my modem/router at the plug it comes back.


Also, my power levels appear to be absolutely fine -

Downstream Receive Power Level: 7.5 dBmV
Upstream transmit Power Level: 48.5 dBmV


I was hoping to get a little insight into whether it is likely to be my modem/connection or my router causing the issue. The fact that the modem's lights remain healthy leads me to believe that it might be my Linksys router.


I have been using this particular connection and modem/router set-up for years and this has never happened before.


Many thanks.

General Maximus
22-05-2011, 22:23
really funny you should say that dude because I have the same problem (used to but dont now). You arent actually being "disconnected" which is why your lights stay on. I have only ever noticed it on sustained high speed data transfers, namely newsgroups and torrents. Everything will run at full speed, then hit 0k for a min or two and then blast off again. I always attributed it to some sort of safety thing VM put on the network. If it was a browser download it would have timed out and thus saved VM the bandwidth, but with it being a torrent or nntp, it will auto resume.

The long and short of it is that it is a teeny tiny inconvenience so I wouldn't worry about it.

Gar
22-05-2011, 22:31
really funny you should say that dude because I have the same problem (used to but dont now). You arent actually being "disconnected" which is why your lights stay on. I have only ever noticed it on sustained high speed data transfers, namely newsgroups and torrents. Everything will run at full speed, then hit 0k for a min or two and then blast off again. I always attributed it to some sort of safety thing VM put on the network. If it was a browser download it would have timed out and thus saved VM the bandwidth, but with it being a torrent or nntp, it will auto resume.

The long and short of it is that it is a teeny tiny inconvenience so I wouldn't worry about it.

Thanks for the quick response.

You mentioned having the same problem but not any more. Did the issue clear up on it's own? How long was it before your problem went away?

I enjoy watching online video streams. Live television for example, so the cut-outs are a little more than a tiny inconvenience for me. They are proving themselves quite disruptive to my online habits. It's not really something I can ignore.

KenK
22-05-2011, 22:54
For the past few days, my internet connection has been randomly dropping. <snip> I was hoping to get a little insight into whether it is likely to be my modem/connection or my router causing the issue. The fact that the modem's lights remain healthy leads me to believe that it might be my Linksys router.I've had a similar problem for years. It doesn't disconnect, it just shuts up; browsing web pages doesn't work for a minute or so; streaming content stops, but recovers ok if I reconnect to it. It's most annoying when a VPN connection to my employer stops in the middle of me trying to fix something. I have a no-name generic router, not Linksys.

I've always put it down to the quality of VMs broadband offering, and simply put up with it.

General Maximus
22-05-2011, 23:36
Tbh I havent noticed it for ages. I havent downloaded anything from newsgroups for quite a while now but I still get a tonne of stuff from torrents. I can't put my finger on a particular date or time but it defo hasnt happened since they increased upload speed to 10:1 or since they implemented p2p traffic shaping (and no, this is not a good reason for doing it before anyone says anything :nono: )

Daz/Teeside
23-05-2011, 12:35
For the past few days, my internet connection has been randomly dropping. It can occur once every ten minutes for a short while, and then it can be okay for hours. Sometimes it will drop once, then be okay for several hours, then drop again, then be okay for another several hours. There doesn't seem to be a pattern (at least not that i can tell).

However, during these drops, my modem lights remain normal. There is no flickering of lights, no reset, etc. It's as if the modem is still holding a connection.

When the connection drops, it comes back on it's own after a minute or two. Or, if I reset my modem/router at the plug it comes back.


Also, my power levels appear to be absolutely fine -


Downstream Receive Power Level: 7.5 dBmV
Upstream transmit Power Level: 48.5 dBmV


I was hoping to get a little insight into whether it is likely to be my modem/connection or my router causing the issue. The fact that the modem's lights remain healthy leads me to believe that it might be my Linksys router.


I have been using this particular connection and modem/router set-up for years and this has never happened before.


Many thanks.

I am having the same problem and have been for a while, it seems to be getting worse lately!

Neo-Tech
23-05-2011, 19:31
Anything in the modem event logs? And setting up a TBB monitor could show something if anything...

Gar
23-05-2011, 20:11
I did a Windows troubleshoot when the problem occured again, and it said the following:

"Windows can't communicate with the device or resource (primary DNS server)"

Any one know what that means? Is it referring to my router?


As for modem logs, this is the only one:

"Critical (3) Started Unicast Maintenance Ranging - No Response received - ..."

Gar
24-05-2011, 01:56
Connection went down for about 5-10 minutes this evening. I checked the logs and it was a wall of this:

Time Not Established Time Not Established Critical (3) DHCP FAILED - Discover sent, no offer received
Time Not Established Time Not Established Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out

Gar
28-05-2011, 15:03
I was hoping it might have fixed itself by now, but I'm still getting drop outs.

Whenever the connection drops, this shows up in the modem logs:

"Started Unicast Maintenance Ranging - No Response received - T3 time-out"

Again, my signal levels are absolutely fine and well within the goldilocks zone.

---------- Post added at 14:03 ---------- Previous post was at 14:01 ----------

I should add, I'm using a 255 VM modem, but I have an older 250 NTL modem handy. Would you advise perhaps trying the older modem? Or would the 250 not be able to handle a 10meg connection?

pip08456
28-05-2011, 17:40
The 250 will handle 10Mb with no problem. I doubt if it is still enabled on the network though so you will not even be able to connect. You need to ring support.

Sephiroth
29-05-2011, 01:14
The T3s will be nothing to do with the router. This is a case where we ought to see the full modem stats (power levels are only part of the story) and event log (your MAC address removed if it appears) as well as the results of a traceroute to www.bbc.co.uk. We might be able to piece togethewr what's going on especially when we see what CMTS you are on.

pip08456
29-05-2011, 01:29
The T3s will be nothing to do with the router. This is a case where we ought to see the full modem stats (power levels are only part of the story) and event log (your MAC address removed if it appears) as well as the results of a traceroute to www.bbc.co.uk. We might be able to piece togethewr what's going on especially when we see what CMTS you are on.

Pedant!!!:D:D:D:D

Kursk
29-05-2011, 03:01
Something is definitely up. For the past couple of weeks my connection's performance is the worst it's ever been. It's like the good ol' dialup days but slower. Single images are downloading in chunks and everything is buffering.

Let's hope it's sorted out soon.

Kursk
30-05-2011, 19:12
Well, things are definitely getting better: my connection is now 4 times the speed it was last time I posted.

It's up to just over 2Mbps. I can pee a faster stream :mad:.

General Maximus
31-05-2011, 00:15
The 250 will handle 10Mb with no problem.

The 250 will handle 30mbit but no more than that. I used to have the Teryaon TJ210 when I was only 10mbit and i had to ring up and get the Ambit 250 for 20 mbit. It was quite funny watching it, I had a 20mbit config file but the TJ210 wouldnt budge above 10mbit. As soon as I connected the 250 it blasted away, the difference was unbelievable.

pip08456
31-05-2011, 00:39
The 250 will handle 30mbit but no more than that. I used to have the Teryaon TJ210 when I was only 10mbit and i had to ring up and get the Ambit 250 for 20 mbit. It was quite funny watching it, I had a 20mbit config file but the TJ210 wouldnt budge above 10mbit. As soon as I connected the 250 it blasted away, the difference was unbelievable.

As it is not a DOCSIS3 modem it's highly unlikely.:D:D:D

General Maximus
31-05-2011, 09:47
cant it do it on docsis 2 if it wanted to? i am sure i read somewhere that it maxes out at just over 30

pip08456
31-05-2011, 09:54
IIRC it's not a DOCSIS2 modem either:D

Peter_
31-05-2011, 09:56
cant it do it on docsis 2 if it wanted to? i am sure i read somewhere that it maxes out at just over 30
They can theoretically run up to 38Mb but not on our platform.

Gar
31-05-2011, 14:43
Small update:

I'm still experiencing the same type of connection drops on a daily basis. Still very intermittent. Everything on my end seems to check out fine, so I'm thinking maybe it's a problem in my general area? Maybe the VM street box?

Masque, is there any way that you could possibly check for known issues in my area? I believe my area code is gors1. If not, how would I find out?

Many thanks.

Peter_
31-05-2011, 15:13
Small update:

I'm still experiencing the same type of connection drops on a daily basis. Still very intermittent. Everything on my end seems to check out fine, so I'm thinking maybe it's a problem in my general area? Maybe the VM street box?

Masque, is there any way that you could possibly check for known issues in my area? I believe my area code is gors1. If not, how would I find out?

Many thanks.
Try te Service Status page if no joy you will need to call in.

https://my.virginmedia.com/service-status/details;jsessionid=7FD8FB6DA2E40D8E50DB0143B740640 D.tomcatmy6

Gar
31-05-2011, 21:30
Thanks. I checked and there are no known issues in my area.

I don't want to have to call support if I don't have to, so I'm seeking to try self-help methods first, just in case it's something I can fix on my own.

I have an old Forward Path Attenuator (10dB) which I have since attached to my modem. Worth a shot right?

Since fitting the attenuator my downstream power level has lowered and now averages about -2.2

Out of curiosity, what at the latest optimum power levels for both downstream and upstream (for a 255 modem)? And what are the highest possible ceiling limits for both downstream and upstream before connection drop-outs (like my own) would occur?

pip08456
31-05-2011, 21:34
They've been here for a loooooooong time if you cared to look!

http://www.cableforum.co.uk/board/12/26006-cable-modem-signal-levels.html

And no they haven't changed!

Gar
31-05-2011, 21:39
They've been here for a loooooooong time if you cared to look!

http://www.cableforum.co.uk/board/12/26006-cable-modem-signal-levels.html

And no they haven't changed!

There's no need to be so rude. I checked that thread but noticed that the last update was in 2009. Which is why I asked for the latest optimum levels (in case things had since changed).

pip08456
31-05-2011, 21:57
There's no need to be so rude. I checked that thread but noticed that the last update was in 2009. Which is why I asked for the latest optimum levels (in case things had since changed).

a) You did't say you'd checked the sticky.

b)Had you said "I've checked the power level sticky are they still the same?"

The answer you would've got would be along the lines of "Yes otherwise the sticky would've been changed!"

Sticky's are there for a reason, pointing it out is not rude!

Gar
31-05-2011, 23:01
Sadly no luck with the attenuator. The connection was okay for a while and then decided to play it's old tricks. Experiment failed.

I meant to do this yesterday (Sorry, Sephiroth!), but here are my modem stats, in full:


Cable Modem Information
Cable Modem : DOCSIS 1.0/1.1/2.0 Compliant
MAC Address : ***
Serial Number : ***
Boot Code Version : 3.1.6d
Software Version : 2.94.1015
Hardware Version : 1.19


Cable Modem Status
Item Status Comments
Acquire a Downstream Channel 402750000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational


Cable Modem Downstream
Downstream Lock : Locked
Downstream Channel Id : 7
Downstream Frequency : 402750000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 7.7 dBmV
Downstream SNR : 41.8 dB


Cable Modem Upstream
Upstream Lock : Locked
Upstream Channel ID : 2
Upstream Frequency : 25800000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 44.5 dBmV
Upstream Mini-Slot Size : 2


Cable Modem Upstream Burst
Req Init Maint Per Maint Short Data Long Data
(1)(3)(4)(5)(6)
Modulation Type QPSK QPSK QPSK QPSK QPSK
Differential Encoding Off Off Off Off Off
Preamble Length 64 128 128 100 80
Preamble Value Offset 396 6 6 396 396
FEC Error Correction (T) 0 5 5 3 9
FEC Codeword Information Bytes (k) 16 34 34 78 232
Scrambler Seed 338 338 338 338 338
Maximum Burst Size 0 0 0 35 254
Guard Time Size 8 48 48 25 134
Last Codeword Length Fixed Fixed Fixed Short Short
Scrambler on/off On On On On On


Cable Modem Operation Configuration
Network Access : Allowed
Maximum Downstream Data Rate : 10240000
Maximum Upstream Data Rate : 1072000
Maximum Upstream Channel Burst : 8160
Maximum Number of CPEs : 1
Modem Capability : Concatenation Enabled, Fragametation Enabled, PHS Enabled


Event logs (wouldn't allow me to clipboard copy, so they are a bit messy):

Tue May 31 20:21:54 2011 Tue May 31 20:21:54 2011 Information (7) The s/w filename specified in the config file is the same as ...
Tue May 31 20:21:54 2011 Tue May 31 20:21:54 2011 Information (7) A software upgrade filename was specified in the config file.
Tue May 31 20:21:54 2011 Tue May 31 20:21:54 2011 Information (7) Authorized
Tue May 31 20:21:54 2011 Tue May 31 20:21:54 2011 Information (7) Registration complete!
Tue May 31 20:21:54 2011 Tue May 31 20:21:54 2011 Information (7) We registered with a DOCSIS 1.1 config file!
Tue May 31 20:21:54 2011 Tue May 31 20:21:54 2011 Information (7) Received a REG-RSP message from the CMTS...
Tue May 31 20:21:54 2011 Tue May 31 20:21:54 2011 Information (7) Sending a REG-REQ to the CMTS...
Tue May 31 20:21:54 2011 Tue May 31 20:21:54 2011 Information (7) CableModem SNMP configure complete
Tue May 31 20:21:53 2011 Tue May 31 20:21:53 2011 Information (7) IP init completed ok
Tue May 31 20:21:53 2011 Tue May 31 20:21:53 2011 Information (7) CableModem TFTP init ok
Time Not Established Time Not Established Information (7) CableModem DHCP client init ok
Time Not Established Time Not Established Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) Started Unicast Maintenance Ranging - No Response received - ...
Time Not Established Time Not Established Information (7) MAP w/initial maintenance region received
Time Not Established Time Not Established Information (7) Downstream sync ok
Time Not Established Time Not Established Information (7) MAP w/initial maintenance region received
Time Not Established Time Not Established Information (7) Beginning initial ranging...
Time Not Established Time Not Established Information (7) downstream time sync acquired...
Time Not Established Time Not Established Information (7) Downstream sync ok
Time Not Established Time Not Established Information (7) starting ds time sync acquisition...
Time Not Established Time Not Established Information (7) Locked on the downstream. Waiting for UCDs...
Time Not Established Time Not Established Information (7) Downstream lock ok
Time Not Established Time Not Established Information (7) Sync Start
Time Not Established Time Not Established Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out


Trace route to BBC website:
Tracing route to www.bbc.net.uk [212.58.246.91]
over a maximum of 30 hops:

1 <1 ms <1 ms <1 ms 192.168.1.1
2 39 ms 8 ms 7 ms 10.217.188.1
3 8 ms 18 ms 8 ms swan-core-1b-ge-300-3842.network.virginmedia.net
[80.0.254.141]
4 14 ms 12 ms 24 ms winn-bb-1b-ge-320-0.network.virginmedia.net [212
.43.162.109]
5 29 ms 14 ms 10 ms winn-bb-1a-ae0-0.network.virginmedia.net [213.10
5.172.161]
6 24 ms 13 ms 16 ms glfd-bb-1b-so-100-0.network.virginmedia.net [213
.105.172.130]
7 42 ms 25 ms 16 ms glfd-tmr-1-ae5-0.network.virginmedia.net [213.10
5.159.46]
8 26 ms 47 ms 15 ms redb-ic-1-as0-0.network.virginmedia.net [62.253.
185.78]
9 14 ms 13 ms 25 ms 212.58.239.249
10 19 ms 34 ms 18 ms 212.58.238.149
11 26 ms 39 ms 36 ms te12-1.hsw1.cwwtf.bbc.co.uk [212.58.239.234]
12 19 ms 24 ms 31 ms 212.58.255.12
13 39 ms 53 ms 42 ms bbc-vip012.cwwtf.bbc.co.uk [212.58.246.91]

Trace complete.



Make of those results what you will, because I'm clueless. Any insight would be greatly appreciated. Thanks.

craigj2k12
31-05-2011, 23:03
Cable Modem Upstream
Upstream Lock : Locked
Upstream Channel ID : 2
Upstream Frequency : 25800000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 44.5 dBmV
Upstream Mini-Slot Size : 2

QPSK modulation indicates noise on the network

General Maximus
31-05-2011, 23:14
is your connection actually working atm? ICMP is an IP protocol which means you must have leased an ip address from the cmts

pip08456
31-05-2011, 23:16
QPSK modulation indicates noise on the network

I'm not replying in case I'm rude again!

Gar
31-05-2011, 23:20
is your connection actually working atm? ICMP is an IP protocol which means you must have leased an ip address from the cmts

Yeah, my connection is working. The drop-outs are temporary and intermittent.

No idea what the rest of what you said means.

General Maximus
31-05-2011, 23:24
I'm not replying in case I'm rude again!

it looks like we are both up for getting our bottoms smacked today

Yeah, my connection is working

I wouldnt worry then dude, as much as a pain in the bum it may be at the moment, if it is just noise on the network which is causing your disconnects (and you can see it by the fact that your upstream is on qpsk which is more noise tollerant that QAM16) it will be fixed shortly.

pip08456
31-05-2011, 23:26
it looks like we are both up for getting our bottoms smacked today

No! Not suspended AGAIN!!!!:D:D:D:D

Gar
31-05-2011, 23:29
I wouldnt worry then dude, as much as a pain in the bum it may be at the moment, if it is just noise on the network which is causing your disconnects (and you can see it by the fact that your upstream is on qpsk which is more noise tollerant that QAM16) it will be fixed shortly.

Good to know, and thank you for the peace of mind.

How long (realistically) do you think I should give it to work itself out, before considering the dreaded phone call?

General Maximus
31-05-2011, 23:33
i hate to say this dude but it really does vary. Last time it happened to me it took 5 days to sort out but that being said, it didnt bother me at all because my connection still performed 100%. The chances are that they know about it already but if i were you i would give them a call just to make sure because disconnects are a pain in the bum

pip08456
31-05-2011, 23:34
Good to know, and thank you for the peace of mind.

How long (realistically) do you think I should give it to work itself out, before considering the dreaded phone call?

Theoretically. without being rude,you should not need to ring it in as it shoukld be picked up automatically.

Peter_
01-06-2011, 00:02
Theoretically. without being rude,you should not need to ring it in as it shoukld be picked up automatically.
If it is a single user issue then it would be unlikely to be picked up so a phone call is in order.

General Maximus
01-06-2011, 00:33
The chances are that they know about it already but if i were you i would give them a call just to make sure because disconnects are a pain in the bum

looks like i was right then :clap:

:LOL:

Sephiroth
01-06-2011, 00:36
Theoretically. without being rude,you should not need to ring it in as it shoukld be picked up automatically.

Quite. Didn't Virgin Media implement "Project Storm" some 9 months ago? A whizz bang monitoring system on all STBs and modems, so that at all times they know exactly what's going on in each locality or indeed at each customer.

pip08456
01-06-2011, 00:38
Quite. Didn't Virgin Media implement "Project Storm" some 9 months ago? A whizz bang monitoring system on all STBs and modems, so that at all times they know exactly what's going on in each locality or indeed at each customer.

Exactly my point. At least you picked up on it!

Gar
01-06-2011, 20:21
Just to give you guys a small sample of what the drop-outs look like:

Download Failed (1)

As you can see, the drop-outs occur in clusters. Coming in, out, in, out, in, out, before stabilizing for what can be several hour periods.

I'll be running the ping montor over the coming days, so I'll have more concrete results to show you then. Hopefully it will give us a better idea of a pattern (if there is one).

Sephiroth
01-06-2011, 20:38
Exactly my point. At least you picked up on it!

But you can be dead sure that none of our VM brothers will have anything useful to say about that.

Peter_
01-06-2011, 20:39
Quite. Didn't Virgin Media implement "Project Storm" some 9 months ago? A whizz bang monitoring system on all STBs and modems, so that at all times they know exactly what's going on in each locality or indeed at each customer.
Well seeming as we still get customers calling in everyday with issues.;)

Sephiroth
01-06-2011, 20:44
Well seeming as we still get customers calling in everyday with issues.;)

... instead of you (VM) using the Project Storm database to fix the issue before the customer calls!

Peter_
01-06-2011, 20:47
... instead of you (VM) using the Project Storm database to fix the issue before the customer calls!
Well I would not have a job then.;):D

Gar
02-06-2011, 13:26
A further example (in case it helps):

Download Failed (1)

As you can see, it started dropping out around 5pm yesterday and continued to do so for roughly 4 hours. Then magically it stopped and levelled out into what was a very stable connection. The internet was in use until around 3am (iPlayer mostly), hence the yellow spikes up until that point.

Then this morning at roughly 9am, the drop-outs began again (for about an hour). The internet was not in use at that time. Since then the connection has stabilized.

I assume 5pm-10pm is a peak time for internet activity, as is 8am-9am? Might this point towards an overload in the area/region causing my woes?

Gar
03-06-2011, 02:26
Interestingly, I checked the status page this evening and it says...

"You will currently be experiencing intermittent connection issues on your broadband internet service. Our engineers are aware of this issue and are currently working to fix it fast. We apologise for any inconvenience this may be causing."

So fingers crossed that the issue they are trying to fix is the same issue that has been causing my woes.

Gar
05-06-2011, 13:06
So the maintenance ended (returned to "Good Service" on the status page), but I'm still getting drop-outs. I've been monitoring my connection for a few days now and there is definitely a pattern. You can see it here:

http://www.thinkbroadband.com/ping/share-large/1ef4ce1f2e0d37dd06cce474cb0bf566-01-06-2011.png

http://www.thinkbroadband.com/ping/share-large/0dcdc88f030200ca7cc435dbc08304ce-02-06-2011.png

http://www.thinkbroadband.com/ping/share-large/777ada804676e6c2795004ceb2dc07ca-03-06-2011.png


Rinse and repeat.

It's always the waking morning hours and peak time evening hours. Between those peak times, the connection is as smooth and as dependable as I would expect.

I assume that this points directly towards it being an issue with high load on in the region/area. In which case, surely their maintenance should have fixed it?