General Discussion
  >> ISP Unhappiness


Register (or login) on our website and you will not see this ad.


Pages in this thread: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | [16] | 17 | 18 | 19 | 20 | 21 | (show all)   Print Thread
Standard User David_W
(experienced) Sun 03-Feb-13 17:37:22
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: matthewcl375] [link to this post]
 
In reply to a post by matthewcl375:
@David_W that's really confusing, because people are saying reboot when the SNRM is highest as this shows less noise on the line, but you say "remember - on the same DSL line, the lower the noise margin, the higher the achievable sync speed. "
Surely if the SNRM is higher then it will give faster sync speed as there is less noise? And conversely, the lower it is, the more noise is being detected on the line, which would result in a lower sync speed?
The line is capable of a particular signal to noise ratio at any time - the more noise, the lower the signal to noise ratio.

The available signal to noise ratio is either in use to provide sync speed, or is spare as noise margin.

Standard User matthewcl375
(regular) Sun 03-Feb-13 17:51:24
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: David_W] [link to this post]
 
@4M2 well so far its only been 7 days since the repair work was done, and over that time I have rebooted the router about 3 maybe 4 times, I've heard it takes 10-14 days of 'stable' connection for the target to be reset by BT

OK I think I get it, if I were to reboot say when my SNR Margin is 16.6db like it is now, the decreased noise on the line that is causing that high SNRM will give me a higher Signal to Noise ratio at sync, which my target SNRM of 15db will then be applied to, resulting in a higher SNR and a hopefully faster sync speed.

Guys, does that sound about right? Only thing left to understand is how @David_W says that rebooting at a lower SNRM can improve sync speed too crazy

Edited by matthewcl375 (Sun 03-Feb-13 17:54:19)

Standard User RobertoS
(sensei) Sun 03-Feb-13 18:19:42
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: matthewcl375] [link to this post]
 
You're getting close, very close in fact smile.

You are slightly mis-reading David's post, because of your remaining bit of confusion, and that mis-reading increases your confusion.

Have another read of my main Noise margin page.

In short, you sort of explained it correctly a few minutes ago. Say there is a Signal to Noise Ratio of 40dB at the time you connect. That 40dB is the most important figure. Your sync-time margin is then used together with that to choose a speed.

If the real noise goes down, the SNR goes up and so does the reported SNRM at the same time. It therefore follows that if your SNRM has risen from 15dB to 17dB that the real noise has fallen and that the SNR has risen.

By doing a re-sync at such a time, because the real noise is less than the previous time, the sync speed will be higher, as that higher SNR is used with the 15dB figure to decide the speed.

The "gotcha" in that is if the noise margin is varying quite a lot at the time. You may catch a bad level of real noise instead of a good one. The higher SNRM on RouterStats needs to be looking stable. By that, I mean over several minutes with no real spikiness.

Does that help?

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 54.3/15.4Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.


Register (or login) on our website and you will not see this ad.

Standard User matthewcl375
(regular) Sun 03-Feb-13 18:48:15
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: RobertoS] [link to this post]
 
@RobertoS makes perfect sense laugh and yea my routerstats is showing a perfectly stable SNRM of 16.6db right now, there has never been any spikiness with my connection apart from obviously when we had the line fault last week, but still I'm not going to restart it as it needs time to show the DLM that its stable. I just like to know what exactly the line is up to tongue

What did David mean by restarting at a lower SNRM to get a higher sync speed?
Standard User RobertoS
(sensei) Sun 03-Feb-13 18:58:18
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: matthewcl375] [link to this post]
 
I don't think he did. Give me the link to the post, to make sure he and I are looking at what is worrying yu.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 54.3/15.4Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
Standard User matthewcl375
(regular) Sun 03-Feb-13 19:06:16
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: RobertoS] [link to this post]
 
Here, the last line or so of it
Standard User XRaySpeX
(eat-sleep-adslguide) Sun 03-Feb-13 19:14:12
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: matthewcl375] [link to this post]
 
In reply to a post by matthewcl375:
What did David mean by restarting at a lower SNRM to get a higher sync speed?
I think you are referring to this:
In reply to a post by David_W:
Remember - on the same DSL line, the lower the noise margin, the higher the achievable sync speed.
He's not saying anything about restarting when you see a low NM but that when you have a lower NM after restarting you should get a faster speed.

1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 19 Meg WBC
Standard User matthewcl375
(regular) Sun 03-Feb-13 19:25:02
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: XRaySpeX] [link to this post]
 
You mean like, if the Target Noise Margin gets moved down and I restart and see a lower margin, then I will get a faster sync?
Standard User RobertoS
(sensei) Sun 03-Feb-13 21:38:56
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: matthewcl375] [link to this post]
 
You are getting deeper and deeper into the mire, when we try to explain what David is trying to say.

Basically he agrees with everything I have told you, but in trying to explain it using a sort of analogy he is blowing your mind. Just forget trying to make sense of that bit of his post. Even I have trouble with it, though what he is getting at is the same as I'm saying.

Go back to what you understood from me before you asked that question smile.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 54.3/15.4Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.

Edited by RobertoS (Sun 03-Feb-13 21:39:14)

Standard User matthewcl375
(regular) Sun 03-Feb-13 23:14:45
Print Post

Re: Slow Internet/low IP profile/high noise margin on Tesco


[re: RobertoS] [link to this post]
 
Right, so all I need to know is that re-syncing when the noise is low (i.e. when the SNRM is higher) will give me the fastest sync I can get with my current target noise margin, but it's a better idea not to reboot to allow the DLM to detect a stable line so it can return the target noise margin to wherever it should be

Resetting my mind to before i asked that question... done tongue
Pages in this thread: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | [16] | 17 | 18 | 19 | 20 | 21 | (show all)   Print Thread

Jump to