Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: Sonac on January 10, 2020, 09:08:33 PM

Title: Questions about linestats.
Post by: Sonac on January 10, 2020, 09:08:33 PM
Hello everyone, i'm quite new to this stuff so please excuse my ignorance.
Over the past few years my internet speed has been steadily dropping from about 65 down (it was once even 70 down) to now anywhere between 45 and 50.

I live in a pretty small village served by cabinet number 1 which appears to be serving just over 1000 customers. I'm very close to my exchange too. My cabinet is a Huawei 288 model.

My current linestats are as follows:

Up Speed: 16584kbps
Down Speed: 59091kbps
Up SNRM: 5.4dB
Down SNRM: 3.2dB (often dips to a noisier 2.9dB)
Line Attenuation: 18.4dB

Speedtest.net results:
48~ mbps down
15~ mbps up

This connection speed drop seems strange to me as I used to have a SNRM of 6dB before BT decided to drop me down to 'improve speed'.

I am using a Huawei hg612 modem but I get roughly the same speeds off the BT smart hub.

I did have a problem a few years back where the BT manhole for the underground lines filled with water (Which is still does) which corroded everything and caused my phone line to crackle like hell. The engineer fixed that. Quiet-line test is dead silent now.

I fail to see why my speed is deteriorating! Any ideas will be appreciated.

Additional settings:
Bitswap = on
CoMinMgn = off
i24k = on
sesdrop = off
sra = on
trellis = on


Title: Re: Questions about linestats.
Post by: Black Sheep on January 10, 2020, 09:21:15 PM
A very high probability the loss is due to cross-talk .... ie: when other people off the same Cab opt to purchase FTTC broadband, your circuit will take a hit.

There's a technology called vectoring that can counter this to a degree .... basically it means a new card has to be fitted in the FTTC cab. But, only BDUK cabs were being retro-fitted with these cards ... not sure of the current position regarding commercial cabs ??

At least you've got the benefit of a sub 6dB SNR, otherwise your circuit would be even slower on 6dB+.

Title: Re: Questions about linestats.
Post by: Sonac on January 10, 2020, 09:27:10 PM
Thanks for the info. I knew i'd take a hit due to cross-talk over time but this drop from about 60-50 has happened within the last few weeks. It seems very strange how it would just slow like that.

I've got a MK4 master socket on the way which i'm going to use to replace my MK2. I've looked up reviews on the MK4 socket and lots of people are seeing some decent gains to speed. Probably due to the better circuitry inside. With any luck i'll get a small bump there.

Interesting to know about the vectoring cards, but a shame they won't be fitted to my cabinet!
Title: Re: Questions about linestats.
Post by: Alex Atkin UK on January 11, 2020, 03:36:52 AM
It happens fast when you get unlucky and someone gets VDSL activated on a line really close to yours in the bundle.

There's really no way to predict how its going to work out.  For example I got VDSL activated on my second line, so they run parallel to each other in the drop wire.  I only lost 1Mbit, but over time from crosstalk things have gotten even worse.  Its cumulative, but not necessarily in a neat pattern you can predict.

The middle shows my two lines shortly after the second was activated, then to either side I added their current state.

(https://csdprojects.co.uk/forums/BroadbandLines.png)
Title: Re: Questions about linestats.
Post by: Sonac on January 11, 2020, 04:20:33 PM
I see. That's unfortunate for me. I'll just have to wait then and see what happens.
I just installed my MK4 master socket. Took me a couple mins to swap out, very easy.
I'll just have to give it a couple weeks to see what DLS does to my profile.

Thanks for the interesting insight!