ASSIA court case forces Openreach to turn off DLM

[#1]

Quote from: AndyH

Quote from: chrcoluk where is this info disclosed publicly? (about the meeting and the commitment). If its not public how do you know. It is disclosed to the industry in monthly meetings - either the NGA working group or copper working group. The changes are summed up by Chris Pettitt many months ago.

Not really sure how things are progressing with this since moving to a different role, but I did have a discussion, along with other ISP's regarding DLM around 8 months ago. Given the recent headline, I've no news on any, if any, impact this may have on the new solution that's being looked at.
Wish I knew more!

[#2]

Quote from: goldenfibre

@ petecov44 - did your speed pick up better after DLM was turned off?

No sir. I am still getting 24mbps down. Tomorrow my account will drop from 80/20 to 40/20 but I suspect this has already happened even though my line rate is still 50.6 as I'm getting a really low throughput
Never mind,

[#3]

You can check your 'Current Line Rate' here: https://portal.plus.net/my.html?action=data_transfer_speed. If that's set at around your speed then it's changed. If it's still higher, then it hasn't.

[#4]

golden fibre, DLM been turned off doesnt mean line profiles will be reset, thats very unlikely as it will cause lines that cannot handle fast path to cause support lines to explode, they will either leave lines on existing profiles or possibly even move everyone to interleaving to play it safe.

[#5]

Quote from: itsme

and other countries don't use DLM? Probably the reason that LLU companies don't use it is they are not prepared to pay royalties or the development costs.

Not true. LLU companies do use a DLM, it's just not the same as BT's. You'll see some Sky customers complaining about theirs
Edit: to be clear, that applies to ADSL2+, On FTTC everyone is stuck with BT's DLM.

Quote from: goldenfibre

Let hope that  ASSIA next step will telling Openreach to get rid of BRAS IP Profile next!

I wish you would learn how DSL works, the IP profile is because of the packet overheads - the headers etc. You can't get rid of it.
@petecove44
Unluckily you just have a [Censored] line and DLM has given you the [Censored] profile to go with it, simples, unfortunately.

[#6]

In my opinion, BT should implement a more intelligent and more responsive DLM based on both current line conditions and hourly historical trends, so that it is less prone to reacting to occasional random bursts of noise, and recovers more quickly when the line quality improves.
In addition, any new DLM algorithm should also take account of peak-time reduced bandwidth caused by exchange congestion, and make the "IP profile" (but not the sync speed) track the average reduced available line bandwidth on an hourly basis, so that the customer's ISP traffic management (QoS) works properly - and therefore would have less packet loss and latency issues, while maintaining the highest achievable speed for the conditions at the time.
For those who don't like the idea of BT "IP profiles" at all, then you are going to hate my suggestion here -
         Can the Plusnet "Current Line Speed" be set permanently to a fixed rate ?
I appreciate that this (forum) topic ONLY applies to BT FIBRE line management,  but the principles of DLM are similar for all BT provisioned adaptive rate broadband products.

[#7]

There is no escaping an IP Profile, I wish people wouldn't give the impression that it could be done away with. It's not a case of "like the idea of BT IP Profiles" it's a fact of life (whilst conceding that 20CN is a different kettle of fish, but this is a Fibre thread).

[#8]

Quote from: purleigh

In my opinion, BT should implement a more intelligent and more responsive DLM based on both current line conditions and hourly historical trends, so that it is less prone to reacting to occasional random bursts of noise, and recovers more quickly when the line quality improves.

I think this is what the ISPs were proposing to Openreach. For FTTC, DLM does react on the side of caution to ensure stability over speed. I do know that one of the proposed changes will be to reduce the caution counters, so a line that has been subject to DLM intervening can recover quicker than at present.
What people seem to forget though is that DLM intervenes for a reason. If there is no intervention, then end users could see a degraded service which would particularly affect those using the service for gaming/IPTV/video conferencing.

Quote from: Chris

Not really sure how things are progressing with this since moving to a different role, but I did have a discussion, along with other ISP's regarding DLM around 8 months ago. Given the recent headline, I've no news on any, if any, impact this may have on the new solution that's being looked at. Wish I knew more!

It's an inevitability there will be custom DLM profiles as well as the option for ISPs to perform resets etc. However, it will take time to develop and test the profiles. There is also the issue of who pays for them.
Hopefully Openreach will give some more info at today's T&D meeting, which PN can share (if they are allowed and someone is going!).

Quote from: Anotherone

There is no escaping an IP Profile, I wish people wouldn't give the impression that it could be done away with. It's not a case of "like the idea of BT IP Profiles" it's a fact of life (whilst conceding that 20CN is a different kettle of fish, but this is a Fibre thread).

I think that the IP Profile is also part of network efficiency, so the BRAS does not send data down faster than your line can handle and cause a bottleneck in the exchange.

[#9]

Your last comment re Network efficiency is perhaps more relevant to Current Line Speed I think.

[#10]

That's more for the CP > BRAS I think.

[#11]

At the end of the day, you can't send data faster than the line can handle, and packet size including headers is relevant to that, that's why an IP Profile exists and it, as well as Current Line Speed, both contribute to overall Network efficiency.

[#12]

Agreed ! 

[#13]

The BT systems will randomly discard packets when an attempt is made to send data down the line faster than the IP Profile. It takes no account of the type of traffic.
The Plusnet Current line speed being set at or a fraction below the IP Profile allows Plusnet to determine which packets are dropped and they do take account of the type of traffic to ensure the lowest priority is dropped first.
Anyone who thinks IP Profile or Current line speed should be dropped is an idiot!

[#14]

Here here.

[#15]

Not really few other isp's doesn't have any form of IP Profile. They think it no point to have both sides. They just leave one by the BT side! This is why is working out well. If BT profile say 77.44Mb and Plusnet profile still on 69.7Mb (will not updated itself for so long and force to ask the staff to match BT profile side)