Kitz Forum
Broadband Related => Broadband Hardware => Topic started by: emgee on April 12, 2008, 11:30:49 PM
-
I purchased a 585V6 from ebay, which arrived yesterday, in an attempt to improve my stats from the DG834G.
First problem I had, was Tiscali branded firmware, although it did accept my ISP details(madasafish). After much digging around, I upgraded to the latest 6.2 firmware and no more Tiscali pages.
The first sync was lower than the netgear, so I restarted a few times and finally got a sync within my 4000 IP profile. At this time, the SNR margin was 12db as it was when the netgear started up. Then, suddenly, it resynced and came back with a 15db margin. It seemed like the DLM raised it at that very moment.
I've lost some speed, but the noise margin has been incredibly stable compared to the netgear. Since yesterday afternoon, the lowest has been 12.5db, even in the evening. During the day, it's a virtual straight line at 15db. I'm synced at 4128, attenuation 47db. Right now, the noise margin is at 14db. The netgear, even with the improved firmware, would normally be varying between about 10 and 4db in the evening, occasionally lower.
I'm impressed with the Speedtouch but clearly, with those stats, there is room for improvement in my speed. The question is, if it remains stable, can I rely on the DLM to reduce my target SNR margin at some stage or should I plead with my ISP to have it done manually?
-
You certainly can't assume that DLM will automatically reduce your target noise margin. I haven't seen a precise definition of this process, but I understand that the error rate is taken into consideration as well as the stability of the connection. If it does work for you it will take at least a fortnight, so it's probably best to wait that long before getting on your knees to your ISP.
-
emgee,
If you drop Metronet-James a PM over on the Thinkbroadband MAAF forum and ask very nicely, I'm sure he'll get your SN target margin reset for you. Did for me, anyway, after I'd been beating my head against a brick wall for a while with CS.
rwm32
-
You certainly can't assume that DLM will automatically reduce your target noise margin. I haven't seen a precise definition of this process, but I understand that the error rate is taken into consideration as well as the stability of the connection. If it does work for you it will take at least a fortnight, so it's probably best to wait that long before getting on your knees to your ISP.
These are the error rates since restarting this morning, uptime 6 hours.
FEC Errors (Up/Down): 0 / 5,945
CRC Errors (Up/Down): 0 / 50
HEC Errors (Up/Down): 0 / 41
I haven't a clue what these mean, perhaps someone can enlighten me.
emgee,
If you drop Metronet-James a PM over on the Thinkbroadband MAAF forum and ask very nicely, I'm sure he'll get your SN target margin reset for you. Did for me, anyway, after I'd been beating my head against a brick wall for a while with CS.
rwm32
Thanks, I'll give that a try soon.
Still very stable margin, varying no more than 3db(12-15) over 24 hours. Should I be aiming to drop right down to 6db, or settle for a safer 9db?
-
You'll certainly get more stability at 9dB, for the loss of somewhere between 300 and 800kbps of sync speed. As I've posted elsewhere, I've had at least 2 re-syncs (both down and up) a day since the reset to 6dB.
However, if you're feeling adventurous, you could load up a slightly older version of firmware that still supports the DMT tool. Then I believe you'd be able to set the SN target margin as desired.
I haven't got any experience of using DMT myself, as it doesn't work with the 7.x.x.x firmware on the 585v7, so I'm going by the 100's of posts on DMT here and elsewhere...
The FEC count shows the errors which your modem has corrected; the CRC and HEC counts show different flavours of uncorrected errors (i.e. errors requiring data to be re-sent from the exchange). Those stats are better than mine for the up-time...
-
Hi emgee.
Glad you're seeing SNR stability improvements with the Speedtouch :)
I told you they were good!
I wonder if you may have re-booted a little too frequently to upset your exchange and increase your target SNR?
In the past I've also had my target SNR reduced thanks to TBB - but FWIW they look at your stats/errors etc. before doing anything, so I would wait a few weeks to see if your target gets reduced 'normally' first.
If your line is stable then your target SNR will get reduced by 3db at a time - but it all depends on the error counts etc.
Good luck...
-
I probably did restart too many times, too quickly. Doh.
Tempting though it is to tinker with it now, I'll take the advice offered and leave it for a while. Thanks for the replies.
-
emgee,
If you drop Metronet-James a PM over on the Thinkbroadband MAAF forum and ask very nicely, I'm sure he'll get your SN target margin reset for you. Did for me, anyway, after I'd been beating my head against a brick wall for a while with CS.
rwm32
Thanks for the tip! I posted on TBB about this on Thursday, was told the DLM could take 30 days to adjust the margin downwards, if at all, or they could do it for me. Less than 24 hours later, it was reset to 9db. My sync went from 4129 to 5536, the highest I've ever had on this line. :) Monitored it last night and it remained perfectly stable, hovering between 7 and 8db. Just waiting for my IP profile to catch up now.
Very pleased with the result, and glad I switched to the Speedtouch.
-
Hi emgee,
Thanks for the update. That sounds like a real result all round :)
Seems like these Speedtouch 585's are life savers to some of us!
-
Sorry not been around for a few weeks so just seen this.
>> If you drop Metronet-James a PM over on the Thinkbroadband MAAF forum
Just worth pointing out the PN + MAAF comms guys (http://comms.plus.net/blog/index.php/2006/08/17/about/#comments) are supposed to monitor these forums too so you should also be able to PM him on here Jameseh (http://forum.kitz.co.uk/index.php?action=profile;u=435),
although theres a couple of others chrisparr (http://forum.kitz.co.uk/index.php?action=profile;u=460) or
orbrey (http://forum.kitz.co.uk/index.php?action=profile;u=787) who visit too.
-
I am also trialing a SpeedTouch (580) after problems with Netgear ADSL 834 G & N modems. I have been experiencing te most wierd behaviour on my line, see attached plot from RouterStats. The SNR jumps up and down all day, by exactly the same about, 14 db. So far the SpeedTouch looks more much stable, but I need a day or two to confirm. Should have more to report in a week or so. I am 2 kms from my exchange. BT have checked the line and found nothing. Has anyone seen SNR behaviour like this before?
[attachment deleted by admin]
-
Occaisionally I see the very sharp dips - like the 4th from the left on your graph on my Speedtouch. The corresponding sync graph shows a disconnect and a resync to the same speed. The router log shows no disconnect. I was wondering if these were an artefact of routerstats rather than a router issue. I sample a 60 sec intervals.
I have never seen behaviour where the margin drops and stays down for several minutes. What does your sync rate do when you see these SNR drops, does your router log show disconnects
-
@MJDalgleish - welcome to the forum - that graph looks a bit like you have quite a localised issue (or at least close to your telephone line somewhere down the line). Are you able to find out if any of your neighbours are experiencing the same perchance?
@Mike, and anybody really - if the routerstats graph keeps dropping down to 3 every time, it could be routerstats (happened all the time on my speedtouch 585 and 576). I'm sure it's something to do with the way routerstats looks for the part in the web page you highlighted.
I think if your up/down line stats are listed next to each other (in the form x / y or something), rather than under separate headings e.g. Upstream: x dB / Downstream: x dB then routerstats doesn't seem to like it when the 'x' changes.
-
MikeS; thanks: The line will sync at 6,500 kbps and 6db SN if the modem is re-booted when there is no noise. When the noise starts, the modem re-syncs at about 2,400 kbps and 6 db SN, where it stays, until it then apparently looses the noise, and the SN then goes back up to 22 db. If I reboot the modem after 10 pm I can hold the 6,500 kbps overnight till the noise next hits.
Mr_Chris; thanks: I will go and see my neighboors on the same local pole. My BT line comes from a local pole 200 metres away and runs parallel to electricity to my house on the same pole, seperated by about 600 mm on the pole. There are two other ADSL users on the same local pole; I will try to see what they are getting. (Nearby neighboors, not on the same local pole, are all getting solid 6,000 kbps at 6dB.)
I have had the same results with Netgear 834G Vers4 and the new NetGear 834N. So its not the modem, nor some interface problem with RouterStats. I have disconnected every mains circuit at the switch board exccept for the modem power; same problem; so its not house generated interference. I have also removed all other devices from the BT circuit, put in an ADSL Nation Faceplate. So its nothing inside the house.
Sadly PLusNet refuse ask BT to look at it because they say there are no disconnects, and that 2 megabits is good enough compared with history on my particular line.
Will report back when I have checked neighbours.
(Another idea I have is to borrow an oscilliscope and see what's on the line at high frequency, when the noise comes on.)
Mike
-
I'm a bit confused by this one...
Your post starts by saying you have switched to a Speedtouch, but your last post looks like you are still using a Netgear. Which router are you currently using?
You SNR graph is very strange (to me) as the lowest things get to seems to be 6db and often around 21db?!?
Normally only people on a fixed product (not max) or people that sync at the maximum for normal ADSL Max see margins like that.
Do you know your target SNR (check just after re-syncing during the day)?
I'm been called for dinner - so I've got to go ???
-
Hi b4dger,
I'm currently using the Speedtouch 580, although I have gotten the same results when I tried the Netgear products.
The line syncs at 3 db and 7,000 kbps with the Speedtouch, when the modem re-boots and apparently the line allows it. I have confirmed with my supplier I am on MAX. Then, when the noise hits, it drops to 2,000 kpbs, still on the same 3 db margin. When the noise goes, the SN jumps up to 20 or so, with the sync staying at 2,000, and then during the day, jumps back and forth 3 db to 20 db as shown on the graph.
I've attached two graphs so you can see this in RouterStats.
The Speedtouch seems to go for 3 db, whilst the Netgear goes for 6 db target noise margin.
Mike
[attachment deleted by admin]
-
Hi - I wonder if the Speedtouch has had it's target SNR tweaked in the past?
I would try a factory reset and then check the SNR...
-
B4dger, thanks,
I thought when I installed the software upgrade to the SpeedTouch Modem/Router, that it would do that. I followed your suggestion and it has booted up with 7 dB SNR and 5376 kilobits. (The modem reports 32,000 FEC Downlink errors, I am not sure if this is normal or excessive.) I wonder if it might hold this configuration? We'll see over the next 24 hours. (I attach the good looking graphs from RouterStats).
By the way, if this improves things, I could try to tweak the modem to say 9 dB. I cant see how to do this since neither versions 7 or 8 of the DMT tool seem to support the SpeedTouch 580. (SoftTouch Software 4.3.x). Can you suggest what I should do if needed to tweak the SNR target to say 9 db?
[attachment deleted by admin]
[attachment deleted by admin]
-
The FEC count shows the corrected errors, so in general don't worry too much about it. If it goes seriously ballistic (into 100s of millions), I'd reboot the modem and forget about it, subject to what else the modem stats are showing.
The CRC error count shows uncorrected errors (i.e. where the data had to be re-sent) and is a better indicator of things to worry about if it does more than creep up by a handful an hour on average. Also worth monitoring Loss of Framing and Loss of Signal in your stats page over a period of time.
I'm not familiar with the 580, but that 4.x.x.x firmware sounds rather old and may not do bitswapping very well if at all, which is pretty important in maintaining stability on lines like mine which get hit by AM frequency interference at night. Anyone else know about this?
Hope this helps
rwm32
edit: corrected typos
-
Thanks to everyone for suggestions so far; sadly to no avail. I am still experiencing SNR jumps at random intervals. (see June 6 12:07 above). Any suggestions/ideas would be appreciated! Mike.