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Standard User Oddball
(fountain of knowledge) Sun 25-Aug-13 22:39:32
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DLM is driving me crazy!!!


[link to this post]
 
Please see this thread for why. It makes no damned sense whatsoever to me.

http://forums.thinkbroadband.com/plusnet/f/4262685-d...

---
What's my speed? Who knows thanks to DLM! Plusnet FTTC. Openreach are pants!
Standard User zyborg47
(eat-sleep-adslguide) Mon 26-Aug-13 09:19:50
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Re: DLM is driving me crazy!!!


[re: Oddball] [link to this post]
 
DLM is evil, another reason why I have no desire to go onto fibre or any DLM ADSL service.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User ukhardy07
(fountain of knowledge) Mon 26-Aug-13 11:30:50
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Re: DLM is driving me crazy!!!


[re: Oddball] [link to this post]
 
There must have been some additional noise / errors to trigger it at some point. DLM runs on your line & it monitors your line individually, so it's not 'broken' it's just doing its job - sadly most of us don't like it.

Crosstalk can cause a line on fibre to lose 10+ Mbps suddenly. Of course you cannot remove the crosstalk, only correct for it via interleaving usually or reduce everybody's output power but that's not going to happen.


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Standard User timl
(member) Mon 26-Aug-13 13:16:54
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Re: DLM is driving me crazy!!!


[re: ukhardy07] [link to this post]
 
Roll on FTTP on demand.

Plusnet unlimited FTTC
Standard User RobertoS
(sensei) Mon 26-Aug-13 19:35:12
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Re: DLM is driving me crazy!!!


[re: timl] [link to this post]
 
You got over £1000 to spend to get it installed? Grrrr! tongue

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 51.8/16.8Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
Standard User adslmax
(knowledge is power) Tue 27-Aug-13 04:10:31
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Re: DLM is driving me crazy!!!


[re: timl] [link to this post]
 
In reply to a post by timl:
Roll on FTTP on demand.


DLM will be on FTTP on demand say BT

plusnetADSL2+15.7 Meg
Standard User timl
(member) Tue 27-Aug-13 06:52:24
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
DLM on a piece of glass!? That's crazy!

Plusnet unlimited FTTC
Administrator MrSaffron
(staff) Tue 27-Aug-13 08:24:21
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Fod is just GEA FTTP so where does Openreach say it will have things like interleaving and other DLM things?

Andrew Ferguson, [email protected]
www.thinkbroadband.com - formerly known as ADSLguide.org.uk
The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User Andrue
(knowledge is power) Tue 27-Aug-13 08:37:03
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Re: DLM is driving me crazy!!!


[re: timl] [link to this post]
 
In reply to a post by timl:
DLM on a piece of glass!? That's crazy!
Yeah. Clearly they've never heard of Rain-X laugh

---
Andrue Cope
Brackley, UK
Standard User adslmax
(knowledge is power) Tue 27-Aug-13 10:18:53
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Re: DLM is driving me crazy!!!


[re: Andrue] [link to this post]
 
Sorry I mean FTTC on demand (not FTTP) apology

plusnetADSL2+15.7 Meg
Standard User Ignitionnet
(knowledge is power) Tue 27-Aug-13 10:54:53
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
What's FTTC on demand?
Standard User adslmax
(knowledge is power) Tue 27-Aug-13 10:56:51
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Re: DLM is driving me crazy!!!


[re: Ignitionnet] [link to this post]
 
I am wrong again. It not FTTC on demand. It actually FTTP on demand. Apology again.

http://www.openreach.co.uk/orpg/home/products/super-...

plusnetADSL2+15.7 Meg
Standard User Ignitionnet
(knowledge is power) Tue 27-Aug-13 10:58:53
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Yes you are - it has no DLM. FTTP doesn't rate adapt, if it can't connect reliably at full rate, 2.4Gb down, 1.2Gb up, it doesn't connect at all or errors like crazy.
Standard User adslmax
(knowledge is power) Tue 27-Aug-13 11:05:23
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Re: DLM is driving me crazy!!!


[re: Ignitionnet] [link to this post]
 
ok then but u could faced a bill of £1000 installation charge! For me FTTPoD isn't worth it for any residental. It will be fine for someone who doing business at home (eg: self employed)

FTTPoD is limit to few exchanges at the moment as it available to these exchanges:

High Wycombe
Bristol South
Edinburgh Waverley
St Agnes
Manchester Central
Basingstoke
Watford
Cardiff Stadium

plusnetADSL2+15.7 Meg

Edited by adslmax (Tue 27-Aug-13 11:06:59)

Administrator MrSaffron
(staff) Tue 27-Aug-13 12:05:54
Print Post

Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Bill could be more but it is your choice to pay it

Andrew Ferguson, [email protected]
www.thinkbroadband.com - formerly known as ADSLguide.org.uk
The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User Ignitionnet
(knowledge is power) Tue 27-Aug-13 12:23:43
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Fortunately it isn't compulsory and FTTC is available with a far lower install charge.
Standard User adslmax
(knowledge is power) Tue 27-Aug-13 12:31:59
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Re: DLM is driving me crazy!!!


[re: Ignitionnet] [link to this post]
 
Virgin Media upcoming 200/20 will be lots cheaper than BT FTTPoD for any installation charge and monthly payment.

plusnetADSL2+15.7 Meg
Standard User Ignitionnet
(knowledge is power) Tue 27-Aug-13 13:23:58
Print Post

Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Also 33% slower, not available to those not in Virgin areas, and not yet officially announced.

Anyway, nothing to do with the non-existent DLM on FTTP.
Standard User zyborg47
(eat-sleep-adslguide) Tue 27-Aug-13 17:53:31
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Re: DLM is driving me crazy!!!


[re: Ignitionnet] [link to this post]
 
In reply to a post by Ignitionnet:
Fortunately it isn't compulsory and FTTC is available with a far lower install charge.

With the dreaded DLM and Bt version of it, no matter what ISp you go with.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User billford
(elder) Tue 27-Aug-13 17:56:35
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Re: DLM is driving me crazy!!!


[re: zyborg47] [link to this post]
 
In reply to a post by zyborg47:
With the dreaded DLM and Bt version of it, no matter what ISp you go with.
The DLM is OpenReach's, and it's a lot friendlier than the BTW version... though I'd agree it would be even better if it wasn't there.

Bill
A level playing field is level in both directions._________________Planes and Boats and ... ______________BQMs: IPv4 IPv6
Standard User RobertoS
(sensei) Tue 27-Aug-13 21:27:20
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Come on Max - you are having a very bad day.

There is no exchange called Manchester Central, and the nearest to that description I know of was fibre-less until recently I believe.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 51.8/16.8Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
Standard User XRaySpeX
(eat-sleep-adslguide) Tue 27-Aug-13 22:13:00
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Re: DLM is driving me crazy!!!


[re: RobertoS] [link to this post]
 
An exchange called Central located in Manchester

1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 20 Meg WBC
Standard User RobertoS
(sensei) Tue 27-Aug-13 23:04:08
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Re: DLM is driving me crazy!!!


[re: XRaySpeX] [link to this post]
 
Thanks smile. I've been caught out by that one before but was able to work out that was it then.


Only some of its areas have FTTC though. It was very late getting anything, as I said.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 51.8/16.8Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.

Edited by RobertoS (Tue 27-Aug-13 23:56:11)

Standard User XRaySpeX
(eat-sleep-adslguide) Tue 27-Aug-13 23:19:31
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Re: DLM is driving me crazy!!!


[re: RobertoS] [link to this post]
 
Blame the GPO! They named these exchanges before it was possible for Central 1234 in Liverpool to dial long-distance to Central 1234 in Manchester without asking the operator to get the # and call you back grin.

1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 20 Meg WBC
Standard User zyborg47
(eat-sleep-adslguide) Wed 28-Aug-13 21:53:44
Print Post

Re: DLM is driving me crazy!!!


[re: billford] [link to this post]
 
In reply to a post by billford:
In reply to a post by zyborg47:
With the dreaded DLM and Bt version of it, no matter what ISp you go with.
The DLM is OpenReach's, and it's a lot friendlier than the BTW version... though I'd agree it would be even better if it wasn't there.


I am pretty sure the system would work ok without it. i know on ADSl, my cable and wireless connection work a lot better without DLM than my BT connection with it.

Maybe Bt should disable it and sere what happens, you never know their equipment may work better.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User adslmax
(knowledge is power) Wed 28-Aug-13 21:59:53
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Re: DLM is driving me crazy!!!


[re: zyborg47] [link to this post]
 
I been ask plusnet to disabled DLM a couple of months ago but the fault team had spoken to BT Wholesale via echat as BT Wholesale rejected it and say the DLM cannot disabled for some reason.

plusnetADSL2+15.7 Meg

Edited by adslmax (Wed 28-Aug-13 22:00:19)

Standard User RobertoS
(sensei) Wed 28-Aug-13 22:32:44
Print Post

Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Maybe because that's the product they offer and if you don't like it you buy someone else's? Same with cars, houses, and baked beans.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 51.8/16.8Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
Standard User jchamier
(eat-sleep-adslguide) Thu 29-Aug-13 08:18:11
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Re: DLM is driving me crazy!!!


[re: zyborg47] [link to this post]
 
In reply to a post by zyborg47:
I am pretty sure the system would work ok without it. i know on ADSl, my cable and wireless connection work a lot better without DLM than my BT connection with it.
Maybe Bt should disable it and sere what happens, you never know their equipment may work better.


(FWIW, C&W is now Vodafone Networks).

The DLM might be bad for a few people, but I suspect the majority of users (whom have never heard of this forum) are better off with it. Most people prioritise stability over ultimate speed, as streaming and downloading and internet banking don't work too well with disconnections.

James BT Infinity 2 19/09/2012 - Sold 42/6 - Getting 46/8 - Sync 50 / 9 Mbps @ 470m approx
14 years of broadband (ntl: cable to BT FTTC) - Router: Asus RT-N66U - Modem: Huawei HG612 speedtest
Standard User timl
(member) Thu 29-Aug-13 08:44:29
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Re: DLM is driving me crazy!!!


[re: jchamier] [link to this post]
 
In my opinion DLM is used by BT mostly to avoid having to fix minor faults with their old copper lines which ultimately saves them money.

For ADSL this worked quite well... though there were a lot of people who love being without it... Talktalk and Sky, O2 and Be.

DLM on FTTC punishes good lines that are ok apart from a bit of occasional noise or crosstalk. We need an option to have it turned off.

Plusnet unlimited FTTC
Standard User billford
(elder) Thu 29-Aug-13 08:50:04
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Re: DLM is driving me crazy!!!


[re: timl] [link to this post]
 
In reply to a post by timl:
DLM on FTTC punishes good lines that are ok apart from a bit of occasional noise or crosstalk.
If it's occasional then in my experience the DLM ignores it.
We need an option to have it turned off.
Not really. An option to reset it after a one-off exceptionally noisy episode might be useful though.

Bill
A level playing field is level in both directions._________________Planes and Boats and ... ______________BQMs: IPv4 IPv6
Standard User RobertoS
(sensei) Thu 29-Aug-13 08:54:23
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Re: DLM is driving me crazy!!!


[re: billford] [link to this post]
 
In reply to a post by billford:
In reply to a post by timl:
DLM on FTTC punishes good lines that are ok apart from a bit of occasional noise or crosstalk.
We need an option to have it turned off.
Not really. An option to reset it after a one-off exceptionally noisy episode might be useful though.
On ADSLx the ISPs have the ability to reset DLM to initial connection defaults, in other words re-run the 10-day "training" period. First-line and even second-line seem generally unaware of this.

But this particular case is FTTC and a different DLM where they cannot.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 51.8/16.8Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.

Edited by RobertoS (Thu 29-Aug-13 08:56:25)

Standard User billford
(elder) Thu 29-Aug-13 08:56:09
Print Post

Re: DLM is driving me crazy!!!


[re: RobertoS] [link to this post]
 
In reply to a post by RobertoS:
But this particular case is FTTC and a different DLM where they cannot.
But that's the fault of BTO, not the DLM...

Bill
A level playing field is level in both directions._________________Planes and Boats and ... ______________BQMs: IPv4 IPv6

Edited by billford (Thu 29-Aug-13 09:01:53)

Standard User RobertoS
(sensei) Thu 29-Aug-13 08:57:47
Print Post

Re: DLM is driving me crazy!!!


[re: billford] [link to this post]
 
I've just done an edit Bill. This isn't applicable to FTTC. I forgot the forum.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 51.8/16.8Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
Standard User billford
(elder) Thu 29-Aug-13 09:02:39
Print Post

Re: DLM is driving me crazy!!!


[re: RobertoS] [link to this post]
 
In reply to a post by RobertoS:
I've just done an edit Bill.
Thanks, so have I wink

Bill
A level playing field is level in both directions._________________Planes and Boats and ... ______________BQMs: IPv4 IPv6
Standard User timl
(member) Thu 29-Aug-13 09:45:19
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Re: DLM is driving me crazy!!!


[re: billford] [link to this post]
 
I can, of course, only speak about my experience. Crosstalk is surely and slowly killing my FTTC connection. DLM doesn't seem to handle this well at all.

So if I can't have DLM off can I have vectoring smile

Plusnet unlimited FTTC
Standard User billford
(elder) Thu 29-Aug-13 10:24:58
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Re: DLM is driving me crazy!!!


[re: timl] [link to this post]
 
In reply to a post by timl:
So if I can't have DLM off can I have vectoring smile
Probably yes... but don't hold your breath tongue

Bill
A level playing field is level in both directions._________________Planes and Boats and ... ______________BQMs: IPv4 IPv6
Standard User Andrue
(knowledge is power) Thu 29-Aug-13 11:15:09
Print Post

Re: DLM is driving me crazy!!!


[re: timl] [link to this post]
 
In reply to a post by timl:
In my opinion DLM is used by BT mostly to avoid having to fix minor faults with their old copper lines which ultimately saves them money.
Which ultimately saves us money and/or ensures they have enough funds to continue investing in the network wink

---
Andrue Cope
Brackley, UK
Standard User Chrysalis
(legend) Thu 29-Aug-13 19:50:26
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Re: DLM is driving me crazy!!!


[re: jchamier] [link to this post]
 
like it fixed (not) robertos current fault? and reacted too late to stop my short term intterment fault (which occured only for 2 hours or so) and even then my fault sitll affected my connection.

DLM in my view is been used to cover up issues with lines, can see also with ignition's recent posts plusnet's reply is to suggest a bump in snrm.

I have seen some posts on the internet where people have lost extreme amounts of sync speed to stability settings, around 50% or more due to very high FEC configured by DLM, I assume in such a situation BT still see it as acceptable as long as the user doesnt complain or the loss of speed occured in a short time period.

I can understand why DLM is there, ultimately it saves BT a ton of cash on fixing local loop issues and reduced calls to tech support. As it does successfully hide various faults albeit after delay (doesnt react right away). But thats all it does it hides.

Where it seems more better is hiding crosstalk errors. A more potent source of errors is too much for DLM to deal with.

For me I would like to see 2 things.

DLM polls the line every hour not every 24 hours, so if something happens, the user doesnt wait until 5am the next morning for DLM to "do something about it" but instead it reacts faster.

When DLM makes a change thats stability related an alert is sent out to engineers when a engineer is auto booked to fix the fault causing DLM, in other words DLM is used as a temporary workaround whilst the fault is been fixed and never used as a long term fix.

BT Infinity 2 Since Dec 2012 - BQM

Edited by Chrysalis (Thu 29-Aug-13 19:55:38)

Standard User Chrysalis
(legend) Thu 29-Aug-13 19:52:27
Print Post

Re: DLM is driving me crazy!!!


[re: billford] [link to this post]
 
In reply to a post by billford:
In reply to a post by timl:
DLM on FTTC punishes good lines that are ok apart from a bit of occasional noise or crosstalk.
If it's occasional then in my experience the DLM ignores it.
We need an option to have it turned off.
Not really. An option to reset it after a one-off exceptionally noisy episode might be useful though.


what happens if you get a burst of noise for 2 hours say once every weeks?

The user of their own free will can choose to disable DLM, have fast path and good line for most of the week and then just put up with the issue for those 2 hours.

Or instead DLM keeps the line perm interleaved as the issue is regular enough to prevent recovery.

BT Infinity 2 Since Dec 2012 - BQM
Standard User billford
(elder) Thu 29-Aug-13 20:07:46
Print Post

Re: DLM is driving me crazy!!!


[re: Chrysalis] [link to this post]
 
In reply to a post by Chrysalis:
then just put up with the issue for those 2 hours.
A speed hungry fibre user tolerating, without complaint, a noisy line for two hours every week?

You jest.

Bill
A level playing field is level in both directions._________________Planes and Boats and ... ______________BQMs: IPv4 IPv6
Standard User RobertoS
(sensei) Thu 29-Aug-13 21:58:29
Print Post

Re: DLM is driving me crazy!!!


[re: Chrysalis] [link to this post]
 
In reply to a post by Chrysalis:
like it fixed (not) robertos current fault?
Phone went dead on Tue 27th. FTTC still worked erratically. Fixed today 16:10 but FTTC not up to speed.

Felt like one wire of the pair disconnected, so if it was making a bad contact for a while that could explain my problem. Too early to tell if my sporadic packet loss is cured, as it seemed to be at TV times.

DLM seems not to have been interested except for my base latency stepping up and down by 3ms or so at times. I'm quite happy with OR DLM.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 51.8/16.8Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
Standard User zyborg47
(eat-sleep-adslguide) Thu 29-Aug-13 22:36:22
Print Post

Re: DLM is driving me crazy!!!


[re: jchamier] [link to this post]
 
In reply to a post by jchamier:
[
[quote](FWIW, C&W is now Vodafone Networks).


Yeah I know, sadly they have also gone for this DLM, but at least users do have a choice to disable it.

The DLM might be bad for a few people, but I suspect the majority of users (whom have never heard of this forum) are better off with it. Most people prioritise stability over ultimate speed, as streaming and downloading and internet banking don't work too well with disconnections.


Most people who don't use these have no idea what DLM is or what it does. Sky DLM is not bad to be honest, it seems to work ok. It is BT version that is a load of rubbish.
No doubt it works better on FTTC, but that is only because copper runs are pretty short from the cabinet. Have a long copper run and it will be as bad as ADSL.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User zyborg47
(eat-sleep-adslguide) Thu 29-Aug-13 22:39:26
Print Post

Re: DLM is driving me crazy!!!


[re: timl] [link to this post]
 
In reply to a post by timl:
In my opinion DLM is used by BT mostly to avoid having to fix minor faults with their old copper lines which ultimately saves them money.

For ADSL this worked quite well... though there were a lot of people who love being without it... Talktalk and Sky, O2 and Be.

DLM on FTTC punishes good lines that are ok apart from a bit of occasional noise or crosstalk. We need an option to have it turned off.


Is it that bad on FTTC? Iin the few FTTC installs I have seen, I have yet to see one work at anywhere near the speed it is suppose to work at.

When I went onto the system I am now, I done so because I thought FTTc would not be here for a couple of years. when it did come here a month or so after, I thought maybe I made the wrong move, but I am sure now that I made the right move and not go to FTTc.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User billford
(elder) Thu 29-Aug-13 22:39:53
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Re: DLM is driving me crazy!!!


[re: zyborg47] [link to this post]
 
In reply to a post by zyborg47:
It is BT version that is a load of rubbish.
No doubt it works better on FTTC, but that is only because copper runs are pretty short from the cabinet. Have a long copper run and it will be as bad as ADSL.
It's clear that you utterly fail to understand that the two DLMs are completely different.

The ADSL one is owned and operated by BT Wholesale, FTTC is Openreach's and they have very little in common.

But don't let me confuse you with facts if your mind is made up.

Bill
A level playing field is level in both directions._________________Planes and Boats and ... ______________BQMs: IPv4 IPv6

Edited by billford (Thu 29-Aug-13 22:40:59)

Standard User RobertoS
(sensei) Fri 30-Aug-13 00:27:33
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Re: DLM is driving me crazy!!!


[re: billford] [link to this post]
 
For example, one major adjustment used by the BTW ADSLx DLM is raising the sync-time noise margin.

That function is completely absent from the Openreach FTTC one.

My broadband basic info/help site - www.robertos.me.uk | Domains,website and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 51.8/16.8Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
Standard User zyborg47
(eat-sleep-adslguide) Fri 30-Aug-13 22:55:01
Print Post

Re: DLM is driving me crazy!!!


[re: billford] [link to this post]
 
In reply to a post by billford:
It's clear that you utterly fail to understand that the two DLMs are completely different.

The ADSL one is owned and operated by BT Wholesale, FTTC is Openreach's and they have very little in common.

But don't let me confuse you with facts if your mind is made up.


I did not realise they was different, so wind your neck in a bit. even so it is still BT,, still the same company and don't give the rubbish they are separate.


i can understand why people went against you when you was a mod.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User billford
(elder) Fri 30-Aug-13 22:58:00
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Re: DLM is driving me crazy!!!


[re: zyborg47] [link to this post]
 
In reply to a post by zyborg47:
even so it is still BT,, still the same company and don't give the rubbish they are separate.
Like I said...

Bill
A level playing field is level in both directions._________________Planes and Boats and ... ______________BQMs: IPv4 IPv6
Standard User zyborg47
(eat-sleep-adslguide) Sat 31-Aug-13 10:32:59
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Re: DLM is driving me crazy!!!


[re: RobertoS] [link to this post]
 
In reply to a post by RobertoS:
For example, one major adjustment used by the BTW ADSLx DLM is raising the sync-time noise margin.

That function is completely absent from the Openreach FTTC one.


Which means? Sorry a bit slow today.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User WWWombat
(fountain of knowledge) Sat 31-Aug-13 11:50:34
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Re: DLM is driving me crazy!!!


[re: zyborg47] [link to this post]
 
In reply to a post by zyborg47:
In reply to a post by RobertoS:
For example, one major adjustment used by the BTW ADSLx DLM is raising the sync-time noise margin.

That function is completely absent from the Openreach FTTC one.


Which means? Sorry a bit slow today.

What it really means is that DLM is a bit of a catch-all name.

There are *many* different schemes that can be used under a broad title of "DLM" whose job is to react to differing line conditions, and attempt to bring stability to the digital comms going on over the line.

Some schemes are more dynamic than other, and can react faster to quick changes to conditions. Some are slower, or even static. Some schemes work well with other lines, while some schemes have a detrimental effect on other lines (I've seen one described as "zap your neighbour first"). Others have a green agenda, and attempt to reduce power usage.

Our understanding of various DLM schemes is advancing all the time, and comparisons made by the likes of Ofcom. An Ofcom subgroup (NICC) has a report on DLM techniques in the UK, but it only reports on a subset of the possible schemes. The Broadband forum has a newer report on DSL Quality Management techniques that gives a broader overview.

The major scheme used by BT Wholesale for ADSL Max and ADSL2+ is one that adjusts the target noise margin after errors (from the 6dB norm to 9, 12 or 15 dB). This scheme (which is the one mentioned by RobertoS) is known as AMA, or Automatic Margin Adjustment.

NICC prefers the newer scheme, known as TRA or Tiered Rate Adjustment, which aims for stability by reducing the sync speed targets into tiers. This is the DLM scheme used by BT Openreach in FTTC.

While BT Wholesale's ADSL Max products only use AMA, their ADSL2+ products start by using AMA but for intractable problem lines, they also have a form of TRA - but this is very much used as the last resort. Openreach FTTC *only* employs TRA.

Both TRA and AMA schemes utilise forward error correction as part of their strategies. The FEC and interleaving changes bring more stability, but the overheads reduce speed and add latency.

For FTTC, however, the specification requirements for the VDSL2 modems bring an alternative mechanism into play - the use of "PHYR", or retransmission at the physical layer. This will do away with the "static" overheads of FEC and interleaving, and replace them with a retransmission overhead that only happens when errors actually occur.

It seems likely (to me) that PHYR will be introduced either alongside vectoring, or afterwards.

Alike? Not even close.
Standard User lexden16
(member) Sat 31-Aug-13 13:11:34
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Re: DLM is driving me crazy!!!


[re: zyborg47] [link to this post]
 
Is it that bad on FTTC? Iin the few FTTC installs I have seen, I have yet to see one work at anywhere near the speed it is suppose to work at.


By way of balance, apart from a blip in Feb, I get 75.3 Down, 16.9 Up with a Latency of 21 at all times of the day so I am very happy with FTTC. That said, DLM does have a marked effect when line conditions go awry. My ISP Line Data shows that it took 16 days from interleaving to drop off after a fault before I got back the full 80/20 profile. It was many days later before interleaving fell away fully and I got back my current max attainable rates of 93.5 Down and 28 Up. I am fortunate as I live c.300M from FTTC cabinet. That said, when people live much further way from their cabinet and the max attainable line speed is less than 80, I can well see why the effects of DLM can be so frustrating.
Standard User zyborg47
(eat-sleep-adslguide) Sat 31-Aug-13 14:52:45
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Re: DLM is driving me crazy!!!


[re: WWWombat] [link to this post]
 
cheers for that, I knew there was different types and some was better than others. Sky seems to have got their's right as i know a few people on Sky ADSl and got longer lines than I have and got a far better sync speed than I did with BT.

I still think that we are better off most of the time without DLM, my connection with Cable and wireless was great, the only time it disconnected was when I pushed the SNR right down. Far better sync speed than I ever had with BT.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User zyborg47
(eat-sleep-adslguide) Sat 31-Aug-13 14:57:43
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Re: DLM is driving me crazy!!!


[re: lexden16] [link to this post]
 
In reply to a post by lexden16:
By way of balance, apart from a blip in Feb, I get 75.3 Down, 16.9 Up with a Latency of 21 at all times of the day so I am very happy with FTTC. That said, DLM does have a marked effect when line conditions go awry. My ISP Line Data shows that it took 16 days from interleaving to drop off after a fault before I got back the full 80/20 profile. It was many days later before interleaving fell away fully and I got back my current max attainable rates of 93.5 Down and 28 Up. I am fortunate as I live c.300M from FTTC cabinet. That said, when people live much further way from their cabinet and the max attainable line speed is less than 80, I can well see why the effects of DLM can be so frustrating.


This is the problem and it seems like the ISPs don't care as long as you got a ok speed. Mate complained to Plusnet and yes they did send a Bt open reach engineer over, who said there was nothing wrong and he should be getting around 70Mb/s as that is the speed the modem is reporting or his equipment,
So i take it that plusnet is traffic managing way too much, they offer these faster speeds and can't cope with the amount of data.

System I am on don't have any DLM, it is 10Mb/s and that is it, ok it does go slightly higher most of the time, but it never drops unless they have a problem and that have not happened for months now.

May only be ten, but I know it is ten.

Adrian

Desktop machine now powered by windows 8 pro 64bit, no dreaded metro , laptop by Mint

ALLPAY Wireless broadband
Standard User kasg
(fountain of knowledge) Sat 31-Aug-13 15:51:57
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Re: DLM is driving me crazy!!!


[re: zyborg47] [link to this post]
 
In reply to a post by zyborg47:
So i take it that plusnet is traffic managing way too much, they offer these faster speeds and can't cope with the amount of data.


I don't understand that comment at all.

Talking of DLM, my modem resynced at 4am today, as you can see from my BQM, and added some interleaving, increasing my latency and decreasing my sync speed by a bit. I'm not complaining, I'm still well above my estimate. This was after the longest period I have ever had without interleaving, 4½ months at the same sync speed. The PPP session didn't drop so I still have the same IP profile, now 99.08% of my sync speed smile

Kevin

plusnet Unlimited Fibre - BQM
Using OpenDNS
Domains and web hosting with TSOHOST
Standard User Chrysalis
(legend) Sat 31-Aug-13 22:18:20
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Re: DLM is driving me crazy!!!


[re: WWWombat] [link to this post]
 
does this PHYR dynamically apply the latency overhead or just the speed overhead?

to me the latency penalty is bigger than the sync speed penalty as many people dont understand the impact of latency on speed.

eg. load a site hosted in asia and one might think asia has some tiny backbone or something and that why its slow, when the real reason is the high latency means the tcp ramps up so slow that the effective speed is slower.

another way I can put it.

a 10mbit connection with 10ms latency to say london will load most websites faster than a 100mbit with 30ms latency. The 10mbit connection will be faster than the 100mbit connection for pretty much all activity that deals with small packets and will hit its max speed quicker on downloads. The 100mbit would win on large file downloads. By small I dont mean tiny as in 1kB, even eg. images that are 250kB will load faster on the first connection as the speed will ramp up quicker.

this is especially apparent when uploading as many applications still use a hard set static low upload buffer size, meaning latency is king on throughput in those situations.

The reasons I consider BTw DLM better than openreach is simple, increasing the snrm still allows the user to overide, (better for user, worse for operator) whilst line banding is a hard cap on sync speed that cannot be overidden (better for operator, worse for user). BTw DLM prefers to raise snrm first ahead of applying interleaving, this to me is a better first choice than applying interleaving. Openreach prefers to apply interleaving ahead of banding. Finally BTw DLM can be reset by the isp, Openreach DLM cannot. BTw DLM also (as I remembered it on adsl max, not sure about 21CN adsl) doesnt forcefully drop line sync to apply new settings, they only applied when the line drops for some other reason, whilst Openreach DLM is disruptive it will drop a line to apply new settings. Ironic since DLM is supposed to help stability yet it causes instability to apply settings.

To me these are all logical reasons why the BTw DLM is better, yet many on here consider openreach's better, I would like to know why.

BT Infinity 2 Since Dec 2012 - BQM

Edited by Chrysalis (Sat 31-Aug-13 22:24:48)

Standard User adslmax
(knowledge is power) Sat 27-Sep-14 19:17:44
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Re: DLM is driving me crazy!!!


[re: billford] [link to this post]
 
In reply to a post by billford:
The ADSL one is owned and operated by BT Wholesale, FTTC is Openreach's and they have very little in common.

But don't let me confuse you with facts if your mind is made up.


What about ADSL2+ DLM run by BTw or BTo?
Standard User RobertoS
(elder) Sat 27-Sep-14 19:39:45
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
BTW. But the IP Profile part of it is also applied on FTTC, at 96.79% instead of the ADSL2+ 88.2%

My broadband basic info/help site - www.robertos.me.uk | Domains,site and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 56.6/14.1Mbps @ 600m. - BQM

"Angels can fly because they can take themselves lightly." - G K Chesterton.

Edited by RobertoS (Sat 27-Sep-14 19:40:12)

Standard User adslmax
(knowledge is power) Sat 27-Sep-14 19:54:11
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Re: DLM is driving me crazy!!!


[re: RobertoS] [link to this post]
 
ADSL2+ 88.2% is pretty low. Should be 96.79%. Would be nice if both are at 98%.

Edited by adslmax (Sat 27-Sep-14 19:55:20)

Standard User RobertoS
(elder) Sat 27-Sep-14 20:31:44
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
ADSL2+ has inherent overheads from using ATM. The IP ADSL2+ IP Profile largely absorbs that and also the TCP/IP overhead.

On O2/Be that didn't have an IP Profile, the highest possible data throughput was about 85%. As the best ISP can put data through BT Wholesale at nearly the IP Profile it isn't an issue.

FTTC doesn't have ATM. Only TCP/IP.

My broadband basic info/help site - www.robertos.me.uk | Domains,site and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 56.6/14.1Mbps @ 600m. - BQM

"Angels can fly because they can take themselves lightly." - G K Chesterton.
Standard User pcoventry76
(knowledge is power) Sat 27-Sep-14 20:32:17
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
In reply to a post by adslmax:
ADSL2+ 88.2% is pretty low. Should be 96.79%. Would be nice if both are at 98%.


When your out of contract I'll happily give you service and access so you can monitor and sort your own line.

As you know tongue
Standard User tdw42
(newbie) Sat 27-Sep-14 21:06:45
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
There is a good A&A article http://aa.net.uk/kb-broadband-how-atm.html which describes why there is such a seemingly large difference between line sync rate and IP throughput for ADSL services.

VDSL2 (aka FTTC) uses PTM which has a significantly lower overhead than ATM so the maximum attainable IP throughput is much closer to the line sync rate.
Standard User adslmax
(knowledge is power) Sat 27-Sep-14 22:35:23
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Re: DLM is driving me crazy!!!


[re: pcoventry76] [link to this post]
 
In reply to a post by pcoventry76:
When your out of contract I'll happily give you service and access so you can monitor and sort your own line.

As you know tongue


Will bear that in my mind. Thanks Pete.
Standard User pcoventry76
(knowledge is power) Sat 27-Sep-14 22:48:44
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
no thank you - it was you who alerted me to the system in the first place!

I owe you one anyway smile
Standard User adslmax
(knowledge is power) Sat 27-Sep-14 22:50:30
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
@ RobertoS - you are correct as my FTTC sync rate 79999k x 96.79% -> BT IP 77.43

see below:

http://postimg.org/image/pxvr1si03/full/
Standard User adslmax
(knowledge is power) Sat 27-Sep-14 22:51:26
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Re: DLM is driving me crazy!!!


[re: pcoventry76] [link to this post]
 
In reply to a post by pcoventry76:
no thank you - it was you who alerted me to the system in the first place!

I owe you one anyway smile


Yes, true enough! wink I want 1Gbps down and up lol without DLM.
Standard User pcoventry76
(knowledge is power) Sat 27-Sep-14 22:56:47
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
If I can ever get that then you got it smile

Right now I'm blowing my mind just looking at all the stats that I have on the test line.
Administrator MrSaffron
(staff) Sun 28-Sep-14 14:24:45
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Re: DLM is driving me crazy!!!


[re: pcoventry76] [link to this post]
 
Offering to resell a service again are we?

The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User pcoventry76
(knowledge is power) Sun 28-Sep-14 15:07:28
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Re: DLM is driving me crazy!!!


[re: MrSaffron] [link to this post]
 
No, I was offering to GIVE free service, is this against a weird and wonderful rule again?

Just so we are clear how much do I need to pay you for you to ignore it like you do when isp reps go into someone else's board to promote themselves?

Seriously, how much? this is clearly why you don't like it and obviously this site would never survive on ads alone so let me know!

Edited by pcoventry76 (Sun 28-Sep-14 15:22:29)

Standard User pcoventry76
(knowledge is power) Sun 28-Sep-14 15:30:23
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Well, at least I have now found a way to provide me with FTTP or FTTPoD if I want. I didn't know this was all part of the package until I just saw it on the wholesale system. Nice one matey smile
Standard User pcoventry76
(knowledge is power) Sun 28-Sep-14 16:06:57
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Re: DLM is driving me crazy!!!


[re: MrSaffron] [link to this post]
 
As per you are really quick to jump on me about this but not so fast to offer a reply.
Administrator MrSaffron
(staff) Sun 28-Sep-14 16:28:13
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Re: DLM is driving me crazy!!!


[re: pcoventry76] [link to this post]
 
Free services are still bound by various rules and regulations, perhaps if you were to describe clearly what you were doing and have a website so people could assess your service it might help us be less sceptical.

As for the accusations, it is hardly the sign of someone you would trust your Internet service with if the person running it is throwing libellous comments around is it?

The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User pcoventry76
(knowledge is power) Sun 28-Sep-14 17:01:29
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Re: DLM is driving me crazy!!!


[re: MrSaffron] [link to this post]
 
I wont provide service to anyone on here anyway - it's a community project with 1 exception

haha! ISPA board/biased - sound familiar?

I don't have a website and I sign people up manually. My word is good in my community and they trust me considering I busted my balls in winter 2000 to get 940 signups for ADSL in 3 feet of snow. I did the same for FTTC having speaking to the local council for several months over it.

Still, if you wish to take action then you do so. I can counter for online bullying x3 (with files full of documented evidence) and that's criminal rather than civil. I am happy to waste your time and money with this.

Edited by pcoventry76 (Sun 28-Sep-14 17:16:11)

Administrator MrSaffron
(staff) Sun 28-Sep-14 17:28:57
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Re: DLM is driving me crazy!!!


[re: pcoventry76] [link to this post]
 
So which providers bribed me?

For the record it was none, but kinda interested to hear who you think it was.

The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User pcoventry76
(knowledge is power) Sun 28-Sep-14 17:47:28
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Re: DLM is driving me crazy!!!


[re: MrSaffron] [link to this post]
 
I never said they bride you I said that every time an ISP rep goes into someone else's area and offers someone service I never see you telling them they are breaking the rules.

So it's clear to see that your attacks are personal on me and me alone. Something else for the law suit which I am now really waiting for you to serve on me, as you think I am libeling you.

Gonna be a blast and more money for my business! smile
Standard User BatBoy
(legend) Sun 28-Sep-14 17:51:34
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Re: DLM is driving me crazy!!!


[re: pcoventry76] [link to this post]
 
In reply to a post by pcoventry76:
I never said they bride
Freudian slip?


______________________________________________________________________________________False_Authority_Syndrome__________________
Standard User pcoventry76
(knowledge is power) Sun 28-Sep-14 19:11:13
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Re: DLM is driving me crazy!!!


[re: BatBoy] [link to this post]
 
In reply to a post by BatBoy:
Freudian slip?


indeed, thanks for pointing that out.

Edited by pcoventry76 (Sun 28-Sep-14 19:16:29)

Standard User adslmax
(knowledge is power) Sun 28-Sep-14 21:23:53
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Re: DLM is driving me crazy!!!


[re: pcoventry76] [link to this post]
 
Keep it quiet yourself pete. Don't let MrSaffron work it out! Glad I found out and surprise we all been ripped off by many isp's to charged too much. That's my goodwill.
Standard User pcoventry76
(knowledge is power) Sun 28-Sep-14 21:25:49
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Re: DLM is driving me crazy!!!


[re: adslmax] [link to this post]
 
Wouldn't matter in any case. And I can see what you mean
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