Beating my head against the wall

[#1]

Hi @BobR1

No problem at all, if you're happy things are resolved for now you can close the complaint ticket 218665783 you've raised online, otherwise someone from our complaints team will pick this up with you shortly. I've left a link to this forum thread on the ticket so they'll be able to see the advice I've suggested as a starting point. 

Obviously feel free to let me know how your connection goes over the coming days or weeks and if you need further help.

[#2]

Hello again Gandalf, the ticket is closed.

But  not because I am happy - far from it. The DLM is misnamed it seems to me - dynamic it is not, except of course when reducing speeds rather than restoring them.

[#3]

No problem @BobR1 let me know how it goes

[#4]

@BobR1  I suggest you look at dslstats under Telnet Data>Connection Stats>stroll down the page until you seen Bearer 0 and what does INPRein say there? I understand DLM on INPRein with very High Retransmission will reduced your speed. There is nothing we can do about it.

See my G.fast Bearer 0 for example:

Bearer 0
INP: 551.00 607.00
INPRein: 0.00 2.00 (red 0.00 is very good low retransmission) as before use to be 10.00 that reduced my G.fast speed)
delay: 0 0
PER: 0.00 484.46
OR: 473.43 168.00
AgR: 22698.95 18742.78

@Gandalf That screenshot (green and pink are very interesting one! Are this a new one along with GEA Test)?

[#5]

@goldenfibre 

Hi, here's what I'm seeing this morning:

INP: 55.00 0.00

INPRein: 1.00 0.00

delay: 0 0

PER: 0.00 8.86

OR:0.01 28.89

AgR:45392.03 10098.97

[#6]

@BobR1 I am not convinced that DLM will by itself get your speed back. The SNRM is way to high. You could try a single resync which should bring it down and as a result increase the sync speed. If it doesn't increase the line must be banded despite @Gandalf  claiming it is not. The profile shown in the GEA test is as always a couple of weeks out of date so doesn't help at all, however it shows you have had periods of much higher speed that you should be able to get back to.

[#7]

@RealAleMadrid Granted a GEA test can show out of date profile data but looking at RRT you can see the profile and the date of that data to be the 10th October. 

@goldenfibre Yeah we’ve had it a while. Really useful. 

[#8]

@RealAleMadrid 

Hi, I agree the SNRM is way too high BUT Plusnet appear to be unwilling to take up that issue with OpenReach. I have actually tried the re-synch you recommend. I did it, if my memory serves, on the day after the powercut that triggered this unsatisfactory situation. At the root of all this is the fact that the graphs that correlate distance from the cabinet with line speed are conservative. So if someone happens to have a good physical connection to the cabinet it is possible to get better than those conservative expected speeds. This is what is bugging me. I have been a Plusnet customer for quite a few years and I can produce evidence of the higher speeds. I assume that their systems have evidence of that too. I want an engineer to come and look at the situation but that would appear to be verboten. What is needed is a re-train.

As I understand it from a Kitz article the DLM operates on a 15min cycle and for a clean re-synch one should drop the router/modem for at least just over 30 mins. I left it for considerably longer.  But it did not trigger any change in the SNRM.

[#9]

I am confident that DLM will automatically reduce the SNRM given time because the target is at 4dB. I've checked RRT again today and the profile is the same with the date now showing as yesterday. RRT profile data is 24 hours behind but it's a massive step up from the profile data on a GEA test. 

Having said that, let's arrange an Openreach engineer visit to investigate further as they may be able to carry out a full DLM reset so I've re-opened your ticket 218665783, could you reply to that with when you'd be available for a visit? 

[#10]

@Gandalf 

OK Gandalf will do and thanks.

[#11]

No problem, I'll reply to the ticket shortly

[#12]

@BobR1  The engineer sometimes refused DLM resetted if found no fault but some will do if asked polite and speak calm with the engineer, he might say ok and might say no. DLM normally resetted by the engineer after the fault is fixed.

As for SNR it will not reduced if the Retransmission set too high, it wait until low then it will work it out to reduced target SNR 3dB.

Your INPRein: 1.00

[#13]

@goldenfibre  The high SNRM is nothing to do with retransmission high mode. It is a higher level of error correction set if the line has a high error rate. Re-tx high is also very difficult to remove, DLM may take weeks or longer or never remove it.

@BobR1  As I said before a Re-sync would immediately show if the line is banded or not so still worth a try. A single resync should not be a problem as far as DLM is concerned.

[#14]

@BobR1 I experienced a similar issue as your original topic: Twice now we have had a power cut and both times internet has gone (intermittently working on 2 or 3 wifi devices). The first time a DLM reset was carried out because apparently we had been "banded" as a result of the cut. This last time it took nearly 3 weeks to resolve and, again, a DLM reset resolved the issue (their faults team refused to do so before, claiming that we had not been banded this time).

Surely Plusnet need to investigate why this issue occurs. This has only started happening recently (we get occasional split-second power outages in my area and it's never been an issue before).

[#15]

@lorddepravus 

Hi and thanks for that information.

As far as being 'banded' is concerned I am told by Plusnet that is not the case for my VDSL connection at this point in time. It would not be the first time however where Plusnet's understanding of the situation differed from what was actually implemented on the OpenReach side.

What is not understood at this point is the post-powercut very high downstream SNRM. I am hoping the engineer call tomorrow will resolve that.