A 2Wire 2700 HGV BT Business Hub Router Wireless

[LesD]

it might be 2 years old but as far as i am concerned new means never used.

Sounds fair Dean but this item of mine was not boxed nor bagged or sealed in any way and jaded was my best way of describing it. Still as I said no worries since it worked OK.

I assume your reply was intended for this post:

http://www.idnetters.co.uk/forums/index.php?topic=8556.msg197332#msg197332

otherwise and simply adding to it with this reply of mine! 

BTW on that post I felt sure you would have a view on the PSU rating/current demand point. 

[LesD]

There are two minor incidents in the event log as follows:

INF  2008-06-03T20:44:06+01:00  sys:  Successfully logged into a password protected page
INF  2008-06-04T19:15:31+01:00  sys:  ppp0: connection lost, reconnecting...
INF  2008-06-04T19:17:16+01:00  sys:  ppp0: Up with ipv4 service on pppoa0
INF  2008-06-04T22:38:19+01:00  sys:  Successfully logged into a password protected page
.
.
.
INF  2008-06-13T21:33:24+01:00  sys:  Successfully logged into a password protected page
INF  2008-06-14T08:56:06+01:00  sys:  dsl0: connection lost, reconnecting...
INF  2008-06-14T08:56:43+01:00  sys:  ppp0: connection lost, reconnecting...
INF  2008-06-14T08:57:01+01:00  sys:  ppp0: Up with ipv4 service on pppoa0
INF  2008-06-14T10:44:43+01:00  sys:  Successfully logged into a password protected page

OK maybe its sad  but I have been trolling through the information in the Management and Diagnostic Console of my 2700 again and under Troubleshooting – DSL Diagnostics at:

http://gateway.2wire.net/xslt?PAGE=J42&THISPAGE=J11&NEXTPAGE=J42

I see Training History and lo and behold the incident at 08:56 that I refer to above is there in all its glory  complete with the Rate before (4448) and the Rate immediately after (4416) the Rate that has been maintained to date and is shown with todays date and the current time each time I refresh the page. 

This Training History info I have found is best displayed in Excel so if you fancy a look I have attached my xls document.

Could these mysterious interruptions I have experienced be down to my line undergoing some sort of training?
I have in mind the "training" that goes on during the first 10 days of a new ADSL connection but for me that was long ago. 


[attachment deleted by admin]

[Steve]

Hi Les As far as I know dynamic line management continues after the training process. The purpose of the training process being to set the maximum stable rate and the fault threshold rate.So presumably the dslam has dropped your sync rate to maintain snr .(thinking out loud)??

[LesD]

Hi Les As far as I know dynamic line management continues after the training process. The purpose of the training process being to set the maximum stable rate and the fault threshold rate.So presumably the dslam has dropped your sync rate to maintain snr .(thinking out loud)??

Interesting Steve and certainly food for thought, thanks. 

[Sebby]

Training is effectively just a term. It is just a period where BT don't have to investigate instability (it's a bit more than this, but that's basically what it is). The DLM is identical during the "training" period and once this period has finished.

If you are losing sync and reconnecting at a similar speed, it indicates surges of noise.

[LesD]

If you are losing sync and reconnecting at a similar speed, it indicates surges of noise.

Yes I see, I am gradually getting a better understanding of these things.

Having had yet another look at my "Training History" I see numbers under:

Mgn1 Noise margin at start of connection
Mgn2 Current or final noise margin

As follows:
   Time             Line             Rate   Max1   Max2   Max3   Mgn1   Mgn2
2008/06/14 08:56:06 BST   1   4448   4468   3952   3952   12.1   5
2008/06/14 08:56:14 BST   1   0   0   0   0   0   0
2008/06/23 21:18:53 BST   1   4416   4444   3220   3220   12.1   9

The Mgn2 at 5 dB on th 14th at 8:56:06 is evidence of such a noise burst. Intriguing!

[Sebby]

It certainly looks that way.

A couple of years ago, this stuff used to confuse the hell out of me, but once you start looking into it, it does make sense. I think a lot of it, especially SNRM, targets, etc, is quite a difficult concept to grasp.

[LesD]

especially SNRM, targets, etc, is quite a difficult concept to grasp.

I see another router's stats (I think it was a Linksys) in another thread reporting noise as SNR (dB)

If this is what it appears to be the number quoted should be absolute Signal to Noise Ratio as opposed to the Noise Margins other routers like the 2Wire and my old Netgear report. I guess bigger is better but if Margin is too big it could result in a lower sync speed.

I have come to think of Noise Margin as the overhead you have in hand over and above the number at which your line should be stable. Signal to Noise Ratio is absolute in that it should be the ratio of how big your signal is (the signal strength if you like) compared to the background noise (white noise) present in the line due to cross-talk, pick-up, interference call it what you like.

I have used the analogy before to the merriment of some but for me  it's similar to a daffodil in a field of grass. If the daffodil is the signals and the grass is the noise, the height of the daffodil above the height of the grass i.e. the difference in height, is the Noise Margin while the height of the daffodil divided by the height of the grass is the Signal to Noise Ratio. (All expressed in decibels of course) Any advance on that? 

[Rik]

No, William.

[Sebby]

[LesD]

Having entered a spell, hopefully a brief one, of unexplained router reboots including the one I complained of elsewhere that lost me 500 Kbps from my IP Profile the other evening, I decided that I would have another go with the MTU in my Router and the PC's TCP/IP set at 1500 instead of the 1458 that I have put my faith in until now.

So far so good and in fact changing the MTU setting in the Router did not force a reboot, which is what I was expecting and had been deterring me before.

I used TCPOptimizer.exe from Speed Guide inc and let the PC reboot to apply the new settings i.e. Registry changes. Once I had my ducks all in a row namely an MTU of 1500 set in the Router and the PC I used TCPOptimizer's Largest MTU tab with www.bbc.co.uk as the destination for the pings and clicked the Start button. Result 1500 MTU was confirmed as OK. 

I retried with www.idnet.com and www.google.co.uk with the same result and have been working with the new setting quite happily for some little while now. 

I was hoping to see an improvement in upload speed but this is not the case as I am still getting numbers like this:
Date 06/07/08 15:32:06
Speed Down 2813.63 Kbps ( 2.7 Mbps )
Speed Up 377.98 Kbps ( 0.4 Mbps )
Port 8095
Server speedtest2.adslguide.org.uk
Which is just the same Up as it was with the MTU set at 1458.


Note the Speed Down is still subject to BT's heavy handedness with my IP Profile. As was stated and restated in another thread it's a right PITA! 

Here's a picture for anyone else who may want to experiment along these lines.

(BTW Simon and Lance the Spell Checker's just great now  again)

[attachment deleted by admin]

[Rik]

Hi Les, have you managed a 5 day stable connection yet, your profile won't budge till you achieve that. I use 1500 throughout myself and have found it gives me a small advantage over 1458.

[Sebby]

I also have MTU set at 1500 on the router, and 1500 on my PC (the ping test reveals that 1500 is my optimal MTU). I find that I constantly get full speed for my profile. I get about 380k/sec upload.

[LesD]

Hi Les, have you managed a 5 day stable connection yet, your profile won't budge till you achieve that. I use 1500 throughout myself and have found it gives me a small advantage over 1458.

No not yet I am still waiting. 
Last time when I suffered the dreaded 135 Kbps BT let me out of jail after 3 days so  for tomorrow.

I also have MTU set at 1500 on the router, and 1500 on my PC (the ping test reveals that 1500 is my optimal MTU). I find that I constantly get full speed for my profile. I get about 380k/sec upload.

Yes I know this should be OK but lest it was finger trouble the last time I tried I had odd effects with some pages loading slowly or not at all as I recall.

As usual time will tell.

Any thoughts on the upload speed point?

[Rik]

Upload speed looks fine unless you're on SuperMax, Les. You will get a faster profile lift if the speed gain is significant.

[Sebby]

Yep, I'd say it looks fine too.

[LesD]

Been up two days now since the last reboot, almost four since the one that docked my IP Profile:

System Time: Monday, July 7, 2008
07:42:25 PM
GMT Daylight Time
Time Since Last Boot: 2  days  00: 25: 00

With these stats:

DSL                           Down  Up
Current Rate:        4448 kbs   448 kbs 
Max Rate:              4448 kbs   1052 kbs 
Current Connection:
Current Noise Margin:  12.0 dB   25.0 dB 
Current Attenuation:  41.4 dB   27.0 dB 
Current Output Power:  19.4 dBm   11.9 dBm 

This evening the sky is ominous, looking thundery and the noise margin is up and down between 10 and 12 dB so who knows? 

The change to 1500 for my MTU is working out OK. I should have done it weeks ago and would have had I known that it would not incur a router reboot.

My IP Profile has recovered to 3500 kbps but the throughput is a bit down on some occasions but it is very likely congestion at my exchange at this time of the evening:

Test at 8:49 PM 7/7/8

Test1 comprises of Best Effort Test:  -provides background information.
    Your DSL connection rate: 4448 kbps(DOWN-STREAM),  448 kbps(UP-STREAM)
    IP profile for your line is - 3500 kbps 
    Actual IP throughput achieved during the test was - 2905 kbps

BroadbandMax has just given me a better result (I like the BBmax Speed tester - I can't think why  )

Results for speedtest    #1215460235
Date of Speed Test: 2008-07-07 20:50:35
Download Speed: 3489 kbps (436.1 KB/sec transfer rate)
Upload Speed: 366 kbps (45.8 KB/sec transfer rate)

The Upload Speed is none to special though. 


I hope you don't mind me posting all this stuff. As much as anything it gives me a nice easy place to refer back to if the need arises! 

[Sebby]

The upload speed is pretty bang on, Les. I max out at about 380k/sec.

[LesD]

The upload speed is pretty bang on, Les. I max out at about 380k/sec.

Yes I can agree with that sort of number as I was seeing 378 kbps pretty regularly myself.

I have done a search to remind myself where I got the idea from that a higher MTU would improve the Upload Speed and it was here in something Mo said:

(The 383 kbps he mentions a bit later on stuck in my head and has had me chasing it I guess  )

http://www.idnetters.co.uk/forums/index.php?topic=7506.msg156263#msg156263

It is qualified or maybe quantified later to relate to quite small differences that may even be swamped out from test to test or between different Speed Testers but I had forgotten the rest of this exchange of information.    I just put it down to the passing of the years but getting the MTU setting up to 1500 is no bad thing. The bigger the bug...  buffer the better what say you!   

[Sebby]

I'm not sure it's the case that reducing the MTU reduces upload speed, Les. I wouldn't worry, I'd say you're getting pretty much the max.

[LesD]

On Wednesday (30 July) I posted this over on Montala's thread, "Starting from cold!"

Time Since Last Boot: 25  days  01: 01: 32

Current Rate:  4448 kbs   448 kbs 
Current Noise Margin:  12.0 dB   25.0 dB 
Current Attenuation:  41.4 dB   27.0 dB

On Thursday evening maybe with Thunderstorms in the air or maybe not, my line dropped and reconnected below 4000 kbps. 
I need 4000 kbps to keep the IP Profile I usually enjoy of 3500 kbps, so one again this profile dropped to 3000 kbps!  (good old BT  )

When I had done for the evening I shutdown the PC and because the sync speed was low I switched off the router thinking that a reboot in the morning would reconnect at over the 4000 kbps and that after three days or so as in the past, I could claw my IP Profile back up to 3500 kbps. 

This was not to be. 
Oh no BT's computer in its wisdom saw this one event on the Wednesday as a major noise event on my line and stuck my Noise Margin up to 15 db. 
At this Noise Margin I have been unable to sync. above 4000 kbps so my IP Profile remains stuck at 3000 kbps 

This is a typical for instance at the moment:

Current Rate:  3872 kbs   448 kbs 
Current Noise Margin:  15.0 dB   25.0 dB 
Current Attenuation:  41.5 dB   27.0 dB

When the noise margin started at 12 db by late evening it would be down to 7 or 8 db.
Now with it starting a 15 db it is typically 10 db by 10 to 10:30 PM.
It's so unnecessary and BT just please themselves even though they or not our ISP.
I know there are a number of us experiencing similar issue as I was spoilt for choice as to whose thread to post my displeasure in! 

With all the  I have put here maybe I should have started a new thread over in "Rant & Rave". 


P.S. After the incident on Thursday that was the catalyst for the reconnection the Current Attenuation went up 0.1dB from 41.4dB to the 41.5dB you will see above. Another one for the slowly but ever increasing attenuation mystery file! 

[Sebby]

Unfortunately, this is one of the many annoyances with BT's systems. There's a chance the the target SNRM will drop automatically in 14 days if you hold sync, but it doesn't always work - it may be worth asking IDNet to see if they can get BT to lower it manually.

That said, if you are losing 5dB between the morning and evening, it sounds like there's quite a bit of noise around later on, so dropping the target SNRM might not be wise at this time as it may just cause instability, then you'll be back to square one!

[LesD]

Since I posted on the 2nd of August my line has been pretty stable apart from one incident a couple of weeks ago when there was Thunder in the locality. Despite this the jump in my Noise margin to 15 dB has never reset.  I guess this is good old BT's fault yet again.

I am collecting router stats at the moment so that I can contact Support with a full picture to see if they can do anything about it. With the Noise Margin at 12 dB I could regularly synch in daylight at just under 4500 kbps but now I cannot get 4000 kbps so my IP Profile is stuck at 3000 instead of 3500 kbps where it used to be. This is just a backdoor way for BT to reduce throughput in my opinion! (Sharp practice or what?) 

I see something in the order of a 6 dB difference after darkness falls so by 10 PM the Noise Margin currently will be about 9 db. When I was seeing 12 dB during the day it would be typically 6 dB after dark.

If I ask Support if I could target 9 dB during the day and it dropped by the 6 dB I see now would my line be unstable after dark at 3 dB say? The attraction of 9 dB is that it might let me synch at over 4500 kbps in daylight and get my IP Profile up to 4000 kbps but its a big if, because instability in the evening would mess it up completely. What a dilemma! What does the forum recommend? 

[Sebby]

Primarily, IDNet may not even be able to get BT to set it manually. BT often believe that if the DLM has increased the target margin to 15dB, then it should stay like that.

If they were able to get them to do it, you right mention the issue of stability. Losing 6dB between day and night is quite large I'd say. That said, 3dB does not automatically mean that the router will lose sync; many people find that it will hold sync all the way down to 0, whilst others find that it drops a bit higher than that. It really depends on your line.

[Rik]

Personally, Les, with that much noise, I'd go for stability rather than speed. The two 2700s I've had have not shown more than a 3db variation on my line, while my Netgear swung through 11db. If you're getting a 6db swing, I'd say the router would have its work cut out to maintain sync at 3db.