re. question ID 91859249

[#1]

Hi
Could someone have a look at my (still open) question 91859249 regarding fttc slowdown following a replacement ECI modem
My download speeds seem to have slowed by approx. 10mps
Further info in question text
thanks in advance
j

[#2]

Hi jonnyfriendly,
I've taken a look through the details of the ticket along with the connection logs and supplier information and it seems that the drop in speed isn't related to the change of the modem but more the flurry of disconnections shown on the 26/09/14 which has meant that the DLM has kicked in on the line and reduced the speeds in order to maintain connection.
I note that the engineer visit was completed on the 24th so these disconnection appear to have taken place after the appointment. Was this something you were doing by way of restarting the equipment or was this drop in connection unprovoked?
The issue we have at this stage is that DLM cannot be reset unless it's done as part of a fault resolution by an engineer at the end of an appointment. Given that this took place after the appointment it would mean that we would now need to await the DLM to uplift the speed as it sees the line is more stable than before. At present there is no tool available to any ISP to request a DLM reset remotely so this isn't something we can request.
I'll leave the support ticket with the faults team for now so that they can pick this up and review the engineer notes and complete the fault process as per it's outcome.

[#3]

Thanks for picking this up.
Yes there would have been some disconnections on the 26/9 as i changed my router.
I'm not really clear as to why the DLM cannot be reset.
If you can't rest it remotely when and how will it be reset (i'm confused) as this will likely cure the problem?
j

[#4]

Sadly BT rules and job divisions possibly union inspired?
You've had a plain old telephone service problem (aka POTS issue) which has crunched the fibre service and brought about aggressive DLM behaviour.  Though the POTS issue has been resolved and the DLM should ideally have been reset on closure of that fault, POTS engineers don't / can't touch broadband services and indeed broadband engineers will avoid POTS issues.
If you'd had a broadband fault, the reset would have been done by the bb engineer on rectification.  To get a reset done requires a bb fault which you never had and have not got.
No it don't make sense, but it is a logical consequence of the illogical way in which BT runs its services. It does not perceive an end user taking a number of services from different suppliers on a single line as a joined up entity where a fault on one service can impare other services on the line.
Resolution of the stupidity requires action from ofcom if they can get permission from Europe to dictate the behaviour of the UK telecoms providers.

[#5]

This sounds ridiculous. Townman, are you suggesting that this issue cannot be resolved ? will it resolve itself ? If so,do you have any idea how long will it take? 
Will Plusnet refund the period of slow speeds - I thought  i entered a contract with them, not BT
Not sure why a Bt engineer cannot be called out, if thats what it takes. You are right its illogical.

[#6]

Hi jonnyfriendly,
I fear that you may have the wrong end of the stick regarding the DLM. This is a safety measure which manages the connection speed in order to maintain a connection. Without it, many people who have faults wouldn't see a drop in speed, instead they would see a total loss of connection instead which I'm sure you'll agree is worse than a drop in the speed.
As you had a phone fault, this has impacted the broadband service which is delivered over the line and caused the DLM to reduce the speed. This means that, as this wasn't a broadband fault, no broadband engineer attended the exchange and a DLM reset wasn't carried out as part of the fault resolution which is why you're still seeing the speed reductions.
Thankfully, DLM works in both directions so as long as the phone line problem has been fixed, you should see the DLM return the speeds over time. I'm afraid there isn't a set time frame for this to happen as this will all be dependant on the DLM seeing proof that the line is back to a fault free state. I would suggest only rebooting your router if there is a real need for it as this can delay the process. If you do find that you need to power off the router for any reason, you should log into the router set up pages and hit the disconnect button and leave this for 5 minutes before powering down the router.
With regards to sending an engineer for a reset to be carried out, this isn't something that BT offer so it isn't something (or any other ISP that operates on the BT network) can request so this will now mean that a wait is in order for the speed to return. As for the discount in subscription while the speed is low, I'm afraid that this wouldn't be possible as the broadband service is designed to operate in this manor.
BT do plan on offering a remote service to reset the DLM without the need for an engineer however this is something they're still working on at present. Hopefully we'll see this tool emerge in the future so that the wait for DLM to reset the speeds in situations such as this will then be a thing of the past.

[#7]

JonnyFriendly,
See here - http://community.plus.net/library/browsing/fttc-dlm-what-it-is-how-it-works/ - for details of how the DLM works.
As Adam hinted, the hands of all ISPs are tied until the new DLM management solutions are released by BT.  It is well accepted that the DLMs ought to behave better, it is my understanding that the control systems are being completely redesigned.
Kevin

[#8]

Thanks Kevin , the link was useful.
Ive been told to wait between 5 - 10 days for speeds to improve.
If you pick this up do you know how i can power off the modem  (i need to put a circuit breaker on the plug) without it affect the DLM ?
Also when it returns to normal, will it do so gradually or suddenly?
thanks for your responses

[#9]

FTTC is not my strong suit, however if one follows ADSL practices and drops the PPP session (router interface) first and wait a few minutes before dropping synch (modem) and then disconnect the modem from the phone line until after the work is completed, then there ought to be minimal impact.
However, fibre DLM is quite aggressive, but hopefully if over all it is stable then the recovery out to happen within nine days... otherwise the longer periods cut in.
Kevin