topic Re: What is happening here? in Full Fibre

What is happening here?

gco — Thu, 04 Nov 2021 11:01:35 GMT

I have unlimited fibre with Plusnet. For the last couple of years I've been getting downstream sync around 35Mbps. When I had a problem some time ago the Openreach engineer said I should be able to get about 50Mbps and that's consistent with what my Vigor router is telling me, so I thought I'd upgrade to unlimited fibre plus. However, it turns out that in the last couple of years things have changed so that if any changes are made to my account the line will now automatically transfer to Plusnet, and as I currently get free line rental with another provider it's simply not worth the extra cost. There seems to be no way round this: I can't even renew my current contract on unlimited fibre to get a discount without triggering the transfer on the line.

So, I'm having to stick with unlimited fibre on standard rolling monthly contract. That leads me to the problem I'm now trying to solve (and which I had hoped would be fixed by changing to unlimited fibre plus). For the past couple of months actual sync has been exactly 30,000Kbps in spite of an achievable of just short of 50Mbps and an SNR margin around 15dB. I asked for a line reset, which I think happened on Monday (the line went up and down a couple of times and the router parameters all changed before settling back down to how they were). Lo and behold, actual sync is still precisely 30,000Kbps with an attainable rate of 49943Kbps (see attached). As the guaranteed speed on the line is lower than 30Mbps I have limited room to complain, but in the past I have always been able to get actual download speeds around 35Mbps which obviously isn't possible with sync stuck at 30,000Kbps! What could be causing this and is there anything that can be done to fix it?

Re: What is happening here?

Baldrick1 — Thu, 04 Nov 2021 11:51:09 GMT

@gco

Have you actually compared the cost of taking a broadband only contract from Plusnet at the out of contract rate and the contracted price including phone? I guess that you are right, but I suspect that the difference in cost is not all that much.

Hopefully a Plusnet staffer will come along and comment on the speed and hopefully provide the results of a GEA test. If you have actually had a DLM reset then I would have expected the SNR to have started at the default 6dB unless there are big noise problems on your line.

Have you tried a quiet line test by ringing 17070 then Option 2? If there is then you need to get this sorted by your freebie phone supplier as this will more than likely be the cause of your speed problem.

Re: What is happening here?

Anonymous — Thu, 04 Nov 2021 13:03:19 GMT

@gco wrote:

When I had a problem some time ago the Openreach engineer said I should be able to get about 50Mbps and that's consistent with what my Vigor router is telling me

What model of Vigor router is this ?,

and does it have the current firmware installed ? (check here - https://www.draytek.co.uk/support/downloads )

Re: What is happening here?

gco — Thu, 04 Nov 2021 13:49:22 GMT

2860Ln with 3.9.1_BT firmware (so yes, latest).

Re: What is happening here?

gco — Thu, 04 Nov 2021 13:56:38 GMT

Thanks for the thoughts.

I've tried a few quiet line tests and got absolutely nothing but I just tried again and thought I might have heard a faint transient squawk - I'm not sure. I can't currently get to the test socket due to other users needing to stay connected, so I'll take it to bits this evening and do the test properly.

I went round the loop on costs but I can't find the details (or I failed to record them). I'll check again. Having said that, nobody seems to be saying that the sync is being limited to this speed because I'm on unlimited fibre rather than unlimited fibre plus, so either way I want to get the connection back to how it was performing until a month or two ago.

Re: What is happening here?

Baldrick1 — Thu, 04 Nov 2021 14:17:01 GMT

@gco

The speed is low because the SNR is so high at 16dB. The question to be answered is why it's so high. Two possible explanations are:

1. The line is banded and you still need a DLM reset.

2. There is high levels of noise on the line which is causing the DLM to trigger.

Or of course, both!

1. Can be only answered by Plusnet doing a GEA test.

2. Might be detected by a quiet line tesst.

Also, have you tried droppimg the DSL connection, leaving it a few minutes then reconnecting? It's possible that things have been corrected and you just need to resync your hub.

Re: What is happening here?

gco — Thu, 04 Nov 2021 14:28:12 GMT

Contract rates (including phone) would be £263.40 and £287.40 for unlimited and unlimited plus.

Current annual cost is £201. Without the contract discount it's £221.88. So either way that's quite a bit more.

However, I'm also being told that out of contract I may have to start paying a higher rate of £261.12 for the current setup (different info coming from different directions). If that's true then the difference is indeed small.

Re: What is happening here?

gco — Thu, 04 Nov 2021 14:36:23 GMT

Yes, I've dropped the connection and powered down the router, with suitable delays, a couple of times. It always comes back exactly the same.

I'll see if I can do a quiet line test this evening, but a GEA test would certainly help.

I asked for a DLM reset at the end of last week. The router sends me a text message every time the connection is dropped, and I had several of them on Monday morning after which the Trellis and Bitswap parameters were different, but half an hour later they had gone back to what they were before. I took this to be the effects of the reset, but without confirmation I can't be absolutely certain.

Re: What is happening here?

adam945 — Thu, 04 Nov 2021 18:12:25 GMT

Hello @gco

Thanks a lot for reaching out and I'm really sorry to hear that you've been having problems with your broadband service. I've just tested the line and can see that it's been banded at 30Mbps. This a symptom of recent disconnections on the line, so simply getting the line unbanded at this stage is unlikely to resolve the underlying issue. It's not clear why the disconnections are occurring though, have you been restarting your router often?

If not, we'd ask that you go through our Troubleshooting Guide to see if you're able to rectify the underlying issue sooner, and to reach out to us if this hasn't helped, and we'll be more than happy to raise it with Openreach and have an engineer appointment arranged.

In regards to the contract, there's little we'd be able to do on our end to be honest, you're right in that we can no longer process re-contracts without taking over the phone line as well. The fact that you're currently getting your line rental for free does make this issue tricker I can understand. Ultimately with that, the choice is yours really.

The graph above shows recent disconnections on the line which have ultimately lead DLM to band your line at 30Mbps. As I said, the drop in speed is a symptom of the underlying issue that's causing the disconnections.

Re: What is happening here?

gco — Thu, 04 Nov 2021 19:12:32 GMT

Thanks for this, and for the call. Sorry I missed you.

In the diagram, the one on Monday was when I think the line reset came through. The ones on Wednesday were my attempts to do some testing. (I tried to get my old Openreach VDSL box into play to see if it would behave differently, but ultimately I didn't succeed - I don't know why. Based on the front panel lights it established a DSL connection but my Draktek router didn't seem to be able to establish an ethernet connection to it. Probably an ethernet configuration problem.) As I said, the 30,000kbps sync has been with me for at least a month, probably more like two months, so whatever the problem is or was must have started or happened that long ago - way before this chart. I have just done a quiet test and it's really hard to tell if there is anything audible on the line. I think I might have heard a few very faint clicks and there is possibly a continuous background noise (my son has also listened and hears the latter) but it is really very faint. I will try a few more tests during daytime (first thing and at lunchtime) and see if I get anything more interesting.

That aside, I've been through everything in the troubleshooting guide with the exception of the factory reset of the router as I'm not sure how easy it would be for me to remember the various configuration changes that have been applied, fixed IP addresses and the like, but I'm sure I haven't done anything in the last few months that would cause this problem.

So we are left with an engineer visit. Is the fact that it's been banded sufficient evidence of a problem to avoid a no fault found callout fee?

Re: What is happening here?

BD — Fri, 05 Nov 2021 11:09:39 GMT

Hi @gco, thanks for getting back to us and confirming the details around the issues you've been seeing further. In which case, I've raised a fault on your account and have looked to progress this further however the fault ticket needs your attention from here:
The fault ticket can be seen and commented on here:
https://www.plus.net/wizard/?p=view_question&id=219374776

Please do give us a nudge on here after commenting on the fault ticket and we can look into progressing this further for you.

Re: What is happening here?

gco — Sat, 06 Nov 2021 21:44:59 GMT

I'm now waiting for confirmation of an engineer appointment to see why the line has been banded and, hopefully, to resolve the problem.

A tip for quiet tests: we found it virtually impossible to tell if there was any faint static/hiss on the line but when we unplugged the phone whilst the test was in progress the difference was very noticeable.

Re: What is happening here?

BD — Mon, 08 Nov 2021 12:33:02 GMT

Hi @gco, thanks for getting back in touch and I can see looking over your fault it looks like our faults team have taken steps to hopefully rid of the drops and issues you've been seeing. We should see by Wednesday if this has worked and if not then we'll happily help progress this further for you with an engineer appointment.
If you've noticed there's less interference on the line without your phone then if possible I'd change the handset to any space you have to see if the drops and problems look to persist. Let us know how it goes.

Re: What is happening here?

gco — Thu, 11 Nov 2021 12:46:13 GMT

After two line resets by the Plusnet team it was still stuck on 30Mbps sync and about 25Mbps download.

An engineer came round, did some tests and reset the line and now it's back up to 40Mbps sync and about 37Mbps download (as it was a couple of months ago), although I see it's interleaved, which it wasn't before. I also noticed that the SN margin drops from around 6dB during the day to as low as 4dB in the evenings. I guess that's crosstalk on the copper stretch when everyone comes home and plays games or watches TV!

Anyway, all sorted in 15 minutes, eventually, thanks to Adam and the team at Plusnet.

The engineer wasn't able to explain why the previous resets hadn't released the banding. We've had similar experiences before. It seems that when the line is reset locally by an engineer it's more effective than a remote reset.

Thanks also to Dabbler for the comment on quiet tests: I had devised just that solution (unplug the phone during the test) just before I read the post, from which it's clear that there is some static/hiss on the line.

Re: What is happening here?

gco — Wed, 17 Nov 2021 11:08:13 GMT

Since things were sorted DLM has intervened several times (I can tell because every time the line is reset my router fails over to wireless and sends me a text message). On Friday morning it switched off interleaving so since then it's been running fast rather than interleaved. However, last night it dropped the sync rate from 40Mbps to 35Mbps so my download speed has dropped from around 37Mbps to around 31Mbps. I am concerned that the next step will be a reduction from 35Mbps to 30Mbps and I'll be back to download speeds in the mid twenties. Is it possible to tell what's triggering DLM intervention and/or, assuming there is interference or noise affecting the line, when it's happening?

Re: What is happening here?

adam945 — Wed, 17 Nov 2021 17:39:11 GMT

Hello @gco

Thanks a lot for reaching out. I'll upload a KBD that I've just run, but the speeds on there are incorrectly showing that the line is syncing at 33.5 Mbps, whereas an RRT is showing the line to be syncing at 39.9Mbps. Can you please upload a photo of your helpdesk page which will show the current data rate? This will give us all a better indication of the current sync speed.

When it comes to FTTC, we can't directly turn interleaving on and off, nor can we directly reset the DLM profile. Openreach adjust this according to the number of disconnections on the line at any given time. If many are found, it'll band the line at certain speeds to preserve stability - so in effect, it's doing it's job.

Nonetheless, please send across a screenshot of your helpdesk page, covering your personal information, and we'll take it

GEA Test Detail
Circuit ID	NA	Service ID


Test Outcome	Pass
Test Outcome Code	GTC_FTTC_SERVICE_0000
Description	GEA service test completed and no fault found .
Main Fault Location	OK
Sync Status	In Sync
Downstream Speed	33.5 Mbps (RRT shows 39.9Mbps)
Upstream Speed	9.7 Mbps
Appointment Required	N
Fault Report Advised	N
NTE Power Status	PowerOn
Voice Line Test Result	Pass
Radio Frequency Ingress	Not Detected
Repetitive Electrical Impulse Noise	Not Detected
Cross Talk	Not Detected
Estimated Line Length In Metres	940.8
Upstream Rate Assessment	Very Good
Downstream Rate Assessment	Reasonable
Interference Pattern	Not Detected
Service Impact	No Impact Observed
Home Wiring Problem	Not Detected
Downstream Policing Discard Rate	0.0
Customer Traffic Level	Upstream and Downstream traffic detected
Technology	VDSL
Current 15Min Bin Retrains	0
Last 15Min Bin Retrains	0
DP Type	External
Profile Name	0.128M-40M Downstream, Interleaving Low - 0.128M-10M Upstream, Error Protection Off
Time Stamp	2021-11-11T00:45:00

Parameters	MIN	MAX	AVG
Down Stream Line Rate	34.9 Mbps	39.9 Mbps	39.6 Mbps
Up Stream Line Rate	9.6 Mbps	9.6 Mbps	9.6 Mbps
Up Time	2.0 Sec	900.0 Sec	892.6 Sec
Retrains	0.0	1.0	0.0

Re: What is happening here?

gco — Wed, 17 Nov 2021 20:36:13 GMT

Here's what I am currently getting from my router.

Some of the stats on your table look as though they come from how it was before DLM intervened last night.

I'm trying to take shots every so often to see if there are any particular times when the error rate increases excessively, but it's very hit and miss. I guess there's no way of getting the data that's used by DLM, which as I understand it provides 15 minute windows.

It's rather irritating that first it removes interleaving and then it bands the line. I'd have thought it would have tried interleaving first.

Gavin.

Re: What is happening here?

gco — Wed, 17 Nov 2021 20:36:57 GMT

and here's what it was before DLM intervened.

Re: What is happening here?

adam945 — Thu, 18 Nov 2021 11:08:34 GMT

Thanks a lot for getting back in touch. Both an RRT and KBD are now showing that speeds have dropped slightly since the last test, though these remain within your expected speeds, so wouldn't reach the fault threshold on our end. DLM will intervene if any drops are seen on the line, in order to preserve it's stability. I'd advise monitoring your connection and seeing how things go over the next week or two.

Feel free to reach out if you have any further issues though.