Different MAC won't do anything, and people have reported mixed results in terms of connection speed from SkyQ modem

There is nothing you can do.

Openreach are aware that some lines do get stuck on sub-optimal profiles, despite line improvements (that court case that BT lost led to changes to the way DLM moves profiles up/down). They are implementing a number of changes to address this, some of which should go live next month.

It does look like ISPs will 'soon' be able to force DLM to reset, but I cannot give you a date. Changes to the DLM algo next month should hopefully make things better for you if you're line is performing well.

Edited by deleted (Tue 28-Feb-17 16:13:30)

In reply to a post by AndyHCZ:

It does look like ISPs will 'soon' be able to force DLM to reset, but I cannot give you a date. Changes to the DLM algo next month should hopefully make things better for you if you're line is performing well.

These are good to know, as I'm sure my upload is artificially limited.

In reply to a post by Fido:

However, although it did at first seem to get faster a minute while the new router bedded in then it was as if the Sky system automatically put the brakes onto the new router as it ended up with the same stats as the old one.

The Sky router connects over VDSL to the green cabinet in the street. That is all run by Openreach. At the green cabinet your data goes over a fibre connection to the handover exchange (may not be your local exchange). Only at the handover exchange is there a connection to any Sky owned hardware.

So all the DLM and management of your VDSL circuit is by Openreach owned hardware and processes. No ISP has any means to do anything on here except call out an engineer to your location - and the engineers can request a DLM reset. These visits cost the ISP lots of money so they don't call them out unless there is a problem the ISP knows needs a human to fix. (e.g. wire faults).

Basically this is why its sold as an "up to" service.

Quite true from my experience, the Q hub doesn't perform as well as some other routers which I why use a separate modem (Billion 8800NL in bridge mode) and connect the hub to that.

An example, I had Openreach out on Monday because my sync speed dropped from 30 Mbps to just above 15 Mbps. There wasn't a fault, just being on a new estate my line had incorrectly connected to a temporary cable that has since been removed. The temporary cable was 400-500m shorter than the cable I'm now connected to, hence the drop.

Anyways, the Q hub only synced at around 13 Mbps compared to the 16.7 Mbps the modem syncs at.

In reply to a post by AndyHCZ:

It does look like ISPs will 'soon' be able to force DLM to reset, but I cannot give you a date. Changes to the DLM algo next month should hopefully make things better for you if you're line is performing well.

AndyHCZ,

Thank you for this information which sounds quite helpful.

When this change does come in and the ISP can force a DLM reset it should really help as it will reset good lines and will highlight lines with issues that the DLM reset does not repair for the longer term and it should help empower ISP's to force Openreach to investigate and repair.

I cannot see anything else for me while I remain with Sky and I cannot see any benefit in moving away from Sky for more costly deals until when/if there are some alternatives to Openreach in my area and Openreach, (which should be nationalised), has no incentive to quickly improve.

Fido

In reply to a post by tommy45:

In reply to a post by AndyHCZ:

Make a change which will reset DLM.

Change of product /speed is one,( 40/10>80/20>40/10 or GEA to Wholesale and the reverse ) not sure if changing the DLM stability profile would also trigger a full DLM reset or not,

Changing the package or changing ISP should result in a DLM reset but in the longer term I suspect that I would be back to square one because I would still be with the virtually uncontrollable and virtually unaccountable Openreach, therefore, in a few months time I would probably be back to where I am now.

Furthermore, (as is usual with Openreach), the target speed for my line has now been lowered so a change in ISP would result in lower targets;

(1). With BT Infinity it is between 30mbps and 40mbps with a minimum of 27mbps.
(2). With Zen it is also between 30mbps and 40mbps but their minimum is 18mbps

I quite like Sky as an ISP and my only real issue with them is that they do not deal with Openreach.

The new system that AndyHCZ was good enough to advise us of where ISP's will be able to force a DLM reset may provide a solution.

Fido

The new algo (assuming you're migrated over to it) will force a DLM reset.

Just to make you aware, that we're talking a tiny tiny percentage of people with 'stuck profiles' (estimates in the region of 1-2% I believe).

Resetting DLM isn't something an ISP should do as a first course of action. In fact, it can be very negative for a line if DLM is not actually restricting it in the first place.

Lines are rate adaptive and a lot of people seem to think that DLM restricts them when in fact it's the target snr margin.

In reply to a post by AndyHCZ:

Lines are rate adaptive and a lot of people seem to think that DLM restricts them when in fact it's the target snr margin.

At previously posted: my Sky Q router stats indicate that the present down Noise Margin is for my line is 9.6

I had presumed that a DLM reset would start afresh, (ie. that it would remove all interleaving and would reset the noise target noise margin to 6).

I know that I can theorectically use my own router, (by fooling the Sky MER system to authenticate my own router after obtaining the Sky MER data from the Sky Q router via Wireshark).

Using my own router would allow me to reset the noise margins, (at least it would have been possible with my Asus DSL-AC68U router that I sold after joining Sky); are there other ways to reset the noise margin ?

Is Sky able to reset the target noise margin or is that down to Openreach ?

Fido

In your case, it's clear the downstream is limited by DLM.

I have no idea whether Sky will do this or not, but if you can get them to run a line check it will show your line performance and send you the results. There is a wealth of information there and it will give you a good idea of what's wrong.

The main issue with DLM is that you used to be able to jump profiles, but that looks like it was removed after the court case.