Question On SNR

Hi

This just a quick question. I'm currently using ADSL2+ with BE and have a 3db profile. With Fibre does DLM aim for a particular SNR, like ADSL, eg 6 db?

Thanks

Yes, FTTC has a target margin of 6dB, it appears.

Thanks, so presumably unlike ADSL2+ where I can lower the SNR to 3db to increase my speed (if the line holds up, which mine does most of the time), because of DLM I will have to keep to the 6db offered? I'm I correct?

Yeah, DLM won't like you setting things manually. Isn't 80Mbps fast enough for you, then?

Thanks! Well, I don't think I'll get 80, estimate looks around 63, but I was only wondering about the technology, rather than lack of speed

There's a BT SIN I was reading saying that manual settings should not be performed. You don't want drop-outs occurring if the SNR is too low, or DLM will take action. Assuming you'll be going with BT of course.

Thanks for the replies, no going with PlusNet from the 22nd from BE. Just asking around the forums out of curiosity!

All FTTC lines are currently maintained by BT OpenReach.

The DSLAM is theirs and the DLM is run by them. No ISP can currently override this.

Lowering the SNR is generally a "bad" idea on FTTC as the instability potentially caused will almost certainly trigger DLM.

Since cross talk will almost invariably be the limiting factor on you line's performance there "may be" nothing to gain.

I would think that the only way to "bodge" the SNR is currently with a FritzBox?

Openreach do allow a very small tailoring of FTTC DLM profile: Standard/Stable/Speed (?)
However, very few ISPs using the infrastructure pass the choice on to customers.
I'm sure someone can post more details if you really need them.

Thanks Stephen & others, only asked out of interest.

Standard, Stable, Super-stable.

I bet Sky use superstable as the DLM is much more sensitive than my BT infinity (or at least it appears that way)

I get the impression no GEA user modifies the OR setting from Standard.

If Sky do, stable sounds more likely, based on their LLU setup. On the WBC ADSLx DLM the three seem to correspond to 6, 9 and 12?/15?, so there is a possibility the OR ones are similar.

In reply to a post by RobertoS:

I get the impression no GEA user modifies the OR setting from Standard.

If Sky do, stable sounds more likely, based on their LLU setup. On the WBC ADSLx DLM the three seem to correspond to 6, 9 and 12?/15?, so there is a possibility the OR ones are similar.

I'm with Sky and the SNR is around 6dB.

And that is Standard .

all the profiles start at 6db but its the trigger points that change, eg. stable has a lower error threshold than standard.

Source link please?