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Signal Noise Ratio... just been talking about it with our friend RL and he mentioned that the higher the better but I thought no, thats wrong...

 

But upon Googling it, I'm getting conflicting opinions about it, some say higher is better, others say lower.

 

Lower makes more sense to me at least.

 

Which is it?

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Signal Noise Ratio... just been talking about it with our friend RL and he mentioned that the higher the better but I thought no, thats wrong...

 

But upon Googling it, I'm getting conflicting opinions about it, some say higher is better, others say lower.

 

Lower makes more sense to me at least.

 

Which is it?

Got this from wiki...   "S/N ratio is defined as the ratio of signal power to the noise power, often expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more signal than noise." so sounds like the higher the better to me, but then again im not a networking guru....yet!!

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Got this from wiki...   "S/N ratio is defined as the ratio of signal power to the noise power, often expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more signal than noise." so sounds like the higher the better to me, but then again im not a networking guru....yet!!

Well, according to that, my line should be ridiculously unstable then... but its pretty much as stable as one can be.

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it is the lower the better.....a modem sets the snr rate according to noise on the line, the more noise on a line there is the higher the snr has to be to compensate. I am on interleaving at the moment as i had a power outage due to a faulty kettle and it caused my line to go into DLM. Under normal conditions i get 75mbps down and 19 up on my line with a downlink snr of 9.0 but when DLM is activated my snr shoots up to around 13 and my download drops until DLM is lifted then I am put on fastpath and my snr drops to 9 again.

 

 

I do have a modem/router where I can adjust the snr myself but that isn't worth doing as it can cause problems. Also as far as I am aware snr manipulation can only be done on DSL lines.

 

 

 

 

B.D

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06. Stability Adjustment (VDSL)


https://www.asus.com/support/FAQ/1015709/


 


 


 


This item allows you to tweak the target SNR Margin of VDSL.


Please go to "System Log - DSL Log", find downstream SNR Margin firstly.


For instance,with a downstream SNR Margin at 8dB, you could set to 7dB or lower to maximize the downstream performance,4dB (Max. performance) but please note the lower value it is, DSL modem router will be weaker to defend the line noise.Therefore, interruption might occur so please adjust with proper value. However, if VDSL connection is unstable or unable to establish a connection, for this case then set to a higher value such as 9dB ~ 30dB.


 


 


 


quoted from asus website.


 


 


 


 


B.D


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Signal Noise Ratio... just been talking about it with our friend RL and he mentioned that the higher the better but I thought no, thats wrong...

 

But upon Googling it, I'm getting conflicting opinions about it, some say higher is better, others say lower.

 

Lower makes more sense to me at least.

 

Which is it?

 

What is your SNR and I'll tell you if it's good or not

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6db has been the default for a long time if you are so far away from the cabinet.

 

If you are close to the cabinet you get more headroom so you may have say 18db if you are right by it.

 

So to have 18db and max throughput is a good next to the cab.

 

If you live away from the cab and you have say 12db DLM has raised your SNRM to stop a EMI ,REIN or SHINE issue, or maybe you have just turned off your modem to many times in one day and the DLM has marked your line as dropping as it can and will do.

 

In the UK 3db SNRM is being trailed right now if your line has no noise and is stable.

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What is your SNR and I'll tell you if it's good or not

 

Was 6, then raised to 12 the same time as my ping... currently on 10. I'm about 3 mins walk from the cab.

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6db has been the default for a long time if you are so far away from the cabinet.

 

If you are close to the cabinet you get more headroom so you may have say 18db if you are right by it.

 

So to have 18db and max throughput is a good next to the cab.

 

If you live away from the cab and you have say 12db DLM has raised your SNRM to stop a EMI ,REIN or SHINE issue, or maybe you have just turned off your modem to many times in one day and the DLM has marked your line as dropping as it can and will do.

 

In the UK 3db SNRM is being trailed right now if your line has no noise and is stable.

I'm 3 mins walk from the cab and mines always been 6 until these issues come up.

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Was 6, then raised to 12 the same time as my ping... currently on 10. I'm about 3 mins walk from the cab.

 

Oh.. yeah I forgot, not USA... Can't help lol

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No idea, the Draytek doesn't tell you this info. Only the SNR and sync speed.

Ah ok, you mentioned a line issue in the shout box, DLM has raised your SNRM to try and stabilize the line, if the line stays stable it will over time drop the SNRM to 6db once again but it will take time.

 

Have you lost sync bandwidth with the higher SNRM?

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Ah ok, you mentioned a line issue in the shout box, DLM has raised your SNRM to try and stabilize the line, if the line stays stable it will over time drop the SNRM to 6db once again but it will take time.

 

Have you lost sync bandwidth with the higher SNRM?

 

They keep messing with it. Sync speed was 80, then 76, then 55, a week ago changed to 62 and literally just now has changed to 58 and SNR raised to 12.

I'm pretty sure there is some kinda problem they are trying to sort... this has been happening for 3 weeks now and I haven't done a thing my end, haven't turned anything off.

Can't see any reason why I'm interleaving.

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You have a line fault and the DLM is dropping your line to add or subtract SNR and interleaving depth's.

 

It is not BT out trying to fix things.

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As Zennon said, I think distance plays a part. I think this sums it up:

 

"Essentially a low margin will allow more speed bur the lower it is the more chance for interference. I have an 80meg connection with a high snr which is optimal because it means my line is capable of very high speeds and also that it can still connect at the high speeds with such a big "buffer" to protect the connection.

 

The higher it is the more stable but the higher it goes the lower your connection will be (unless you're close enough to the cab like me to get the full whack with a high SNR"

 

I found it weird that my modem stats on my Smart Hub don't seem to line up with what's considered "good" or "typical", yet I've never had anything less than my estimated bandwidth, which just happens to match my guaranteed minimum and is what I pay for lol

 

My new modem says this. Not really sure if that's good, expected or typical lol. Should add I could hit my cab with a stone throw from my kitchen window.

post-9329-0-95010900-1515795525_thumb.png

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I found it weird that my modem stats on my Smart Hub don't seem to line up with what's considered "good" or "typical", yet I've never had anything less than my estimated bandwidth, which just happens to match my guaranteed minimum and is what I pay for lol

 

 

Same. I've always gotten pretty much the max speed possible, pretty much whats paid for. On Virgin for some reason I seemed to get 213mb outta the 200mb we were paying for lol.

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You have a line fault and the DLM is dropping your line to add or subtract SNR and interleaving depth's.

 

It is not BT out trying to fix things.

 

When I get the chance, I'll plug the BT HH back in and post my line stats. Won't be for a few days due to work though.

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Same. I've always gotten pretty much the max speed possible, pretty much whats paid for. On Virgin for some reason I seemed to get 213mb outta the 200mb we were paying for lol.

On 50/3 I got no less than 53Mb down. On 100/6 it rarely reached 50, often dropped to 20 and the max I saw was 80... for one day LOL

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