Just had FTTC installed. Interpreting line stats

So upgraded from ADSL to FTTC. 38/10 service. These are my line stats which i expect

Connection Speed 39994 kbps 9997 kbps

Just not sure what these mean:

Noise Margin D0( 9.6) D1( 9.6) D2( 9.6) dB U0( 12.9) U1( 10.2) U2( 10.3) U3(N/A) U4(N/A) dB

On ADSL you had 1 noise margin, now i have multiple ones. So what do they all mean?

Also these are my results - https://www.thinkbroadband.com/speedtest/16933011327...

Upload seems a abit slow for the sync speed? Or is that normal? Im guessing download is normal as you never get the full sync speed due to overheads etc

Edited by bobble_bob (Tue 29-Aug-23 10:29:12)

You've only given a snippet of the stats, a full set might be more helpful.

Sync speeds are good, full speed for your service. Upload throughput a bit low.

The noise margins you have shown are split into the various Downstream and Upstream frequency bands and look good, (N/A) means the band is not in use which is normal for the higher upstream bands.

The router stats may also show single average values for DS and US margins.

Thats the only line stats available on the D6400 Netgear router that i know of

Any reason the upstream would be slightly low? Not much of an issue i dont really upload much anyway

In reply to a post by bobble_bob:

Any reason the upstream would be slightly low? Not much of an issue i dont really upload much anyway

What was you expecting?

Edit: OK I just looked at the speed results it may be congestion.

Edited by deleted (Tue 29-Aug-23 10:54:48)

Well syncing at 9997 kbps i was expecting maybe 7Mbps at least

Maybe im wrong?

Edited by bobble_bob (Tue 29-Aug-23 10:54:27)

In reply to a post by bobble_bob:

Well syncing at 9997 kbps i was expecting maybe 7Mbps at least

Maybe im wrong?

Just updated my last post after looking at speed results. Test at various times of the day to get a better overview.

Yea will do. What speeds would you expect to see for that sync? Its still 5 times fast than what i was on before so cant really complain.

Downstream seems spot on which is the main thing

Edited by bobble_bob (Tue 29-Aug-23 11:01:43)

The SNRs look good - tyically 9 on the Down and 12 UP. Ypu are hitting max - almost on down, but up is definitely a little low especially with 12dB..

Keep doing wired tests and various times of te day and see if it is stuck fast!

I decided to use the pre-existing Cat5 extension cable i had with ADSL. It adds about an extra 12m of internal wiring so i can have the router where i want it. Perhaps that is causing the slowness, although i would have thought it would have effected download too which it isnt.

I will try with a smaller cable see if that helps

Try that ...


It is always worth having a decent cable, but my brain has gone dead, and cannot remember if FTTC is an RJ11/12 output - I think it is. If so, have a look at Kenable for their ADSL+ cables made with 2 pair Cat5e:

https://www.kenable.co.uk/en/107-adsl-rj11-cables?le... other lengths available, the ones at £3.10 / £3.26 depending on colour.

I installed a 2m one for someone to replace their ISP supplied one and immediatley the speed jumped bu about !0Mbps (down) not pronisig it in your case, but decent cables are worth it - especially at those prices.