Noise Margin?

[iggyb]

Hi

I do not have a problem but am curious about the Noise Margin value shown in my router figures below

Most information is that this should be about 6dB. Everything else looks OK and the Maximum data rate is high.

Iain

[Keith_Beddoe · Accepted solution]

What broadband package are you on, as your speed may be limited to 55Mbs, even though your max rate is 129Mbs?

If you are on a lower rate package, then you will see a larger noise margin, as the line is capable of a higher speed.

[iggyb]

I am on Superfibre 1 which has an avertised speed of 50mb.

From what you say this is the cause of the high noise margin.

Thanks

Iain

[Keith_Beddoe]

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@iggyb wrote:

I am on Superfibre 1 which has an avertised speed of 50mb.

From what you say this is the cause of the high noise margin.

Thanks

Iain

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That is correct. A large noise margin indicates there is plenty of spare transmission capacity, should you decide to upgrade to a higher speed. Your connection speed is being restricted at the moment.

[iniltous]

AFAIK, because your max attainable is way excess of your (capped at 55Mb) data rate, the noise margin can be left 'high' as you have plenty of headroom between what you pay for and what the line is capable of delivering, so although 6dB is a target , in your case you don't need a 6dB margin to get 55Mb, so the line management doesn't need to lower it to 6dB ,

[pippincp]

@iniltous The noise margin is not "left high". A lot of people refer to target NM are actually referring back to ADSL days as with VDSL it becomes quite different in a certain way.

For those who's distance from the cab reduces their connection speed then the target may well be 6dB unless of course they are on a 55 Mb package but could get 60 or 70Mb then the NM will be more than 6dB.

Then we can throw G.INP into the mix which if active will reduce NM to around 3dB.

VDSL is a different beast compared to ADSL and operates on a different band of frequencies although there are overlaps.