Minimum Guaranteed Speed MGS changed during contract.

[#1]

It's clearly a disconnection, but as I said before, this looks like a maintenance disconnection - these usually occur between 1am and 5am. What cabinet are you on? 

Another matter is that Plusnet are inept at solving any complex problems to do with Openreach. We've been battling more regular disconnections (during the day) for the past year now ... and Openreach are not fixing our line, despite knowing that there's a high resistance fault on it. 

Yet another matter is that this VDSL stuff is not fit for purpose. It's new technology that uses old copper wires. It's like baking an expensive cake in an old and flaking tin... 

[#2]

Thanks for getting back to me @dejjones

You're connected via L2TP, which means your line speed is subject to two separate speed profiles, Openreach's (DLM), and our internal Workplace profile. On Openreach's side, the KBD that I've popped below shows that the line isn't banded at all, and that sync speeds are still within your estimates, slightly above in fact. I can see another drop during the early hours of the morning, but as the 30 day radius shows, the line remains relatively stable.

We don't micro-manage connections @dejjones - meaning we won't raise a fault based on one or two drops that occur every so often, an engineer is likely to go out and find a working line.

I've just reset our internal workplace profile back to 40Mbps, as it's come down a little, trying to stay as close as possible to the current sync speed.

KBD

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	40.0 Mbps
Upstream Speed	10.0 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	659.0
Upstream Rate Assessment	Very Good
Downstream Rate Assessment	Very Good
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, Retransmission Low - 0.128M-10M Upstream, Error Protection Off
Time Stamp	2021-12-10T15:45:00

Parameters	MIN	MAX	AVG
Down Stream Line Rate	39.9 Mbps	39.9 Mbps	39.9 Mbps
Up Stream Line Rate	9.9 Mbps	9.9 Mbps	9.9 Mbps
Up Time	861.0 Sec	900.0 Sec	899.9 Sec
Retrains	0.0	1.0	0.0

Radius

[#3]

@adam945

Sorry to be a pain but your post raises more questions than it answers, to a non telecom layman like me.

1.

You say the "line is subject to two separate speed profiles".

One you said is the "internal workplace profile" (now set at 40 Mbps); what is the other one.

2.

How do these profiles relate to the IP Profile and the Current Line Speed (CLS)? (currently 38.67 Mbps & 37.0 Mbps)

3.

How does the GEA Test Detail relate to the profiles, it doesn't seem to mention any of them.

4.

Why did the disconnection on Dec 21st reduce the IP Profile and the CLS, but the disconnection on Dec 23rd raised them.

I don't recall  the IP Profile or the CLS being raised before, without PN requesting it.

@Edinburgh_wg 

You ask "what cabinet am I on" I don't understand; my package is FTTC is that what you are asking?

I have no idea what's causing the disconnections but what sort of maintenance do you suggest is going on at 3am,  and the disconnections last less than a minute?

[#4]

Sorry to intrude but perhaps I can help answer this.

Our internal workplace profile is known as the Current Line Speed on your side and should sit around the IP profile, which is between 90 to 96% of your sync speed. These profiles respond to changes in the sync speed  

A GEA test doesn’t show this, but it does show the sync speed and you know the IP profile from other means. 

It’s hard to investigate single drops especially overnight as they’re likely down to maintenance. Each time you have a drop in your broadband connection, there’s a chance your modem will ‘renegotiate’ a new sync speed with the cabinet (the green box in the road).

As a general rule, unless there’s an issue showing on our testing, our suppliers consider an intermittent connection worthy of investigating to be 3 drops within the last 24 hours or 6 drops within the last 72 hours. 

It is odd though that the drops you’re having seem to be artificially restricting your speed as evidenced by the line resets we’d requested to remove the restriction, so if this continues to be a regular thing, as I’ve noted previously, I wonder maybe if it would be best to arrange a broadband engineer to take a closer look. 

Also this may help provide further insight: https://community.plus.net/t5/Library/FTTC-DLM-What-it-is-How-it-works/ba-p/1322799

[#5]

@Anoush

Thanks for your input, it's welcome, I can't imagine why you think you are intruding.

My motivation for raising these issues, hasn't really been because I think there's a fault, it's because I'm trying to understand how things work and what causes the early morning disconnections, and the info. in your link was really useful.

As I said earlier my speeds and stability have been as good as ever over the last 3 weeks.

From my router event log there have been about 30 disconnections since March 2021 (I'm defining disconnections as "DSL link down" events), 18 of them have been the single events occurring between  1.09 am and 3.44 am. Most of the other disconnections are down to OR engineer visits and my own testing etc.

So the 18 look for all the world like maintenance disconnections; except they don't fit the time frame, according to your link (3.00 am to 5.00 am)

Also the info says the DLM is making it's overnight changes based on the previous days record. I have had virtually no daytime unexplained drops/disconnections for months, so what problem is the DLM seeing that results in the maintenance events?

[#6]

Ah no problem, makes sense. 

It’s definitely a tricky one, and it’s hard to say what’s causing the drops overnight if not maintenance or DLM related as your line remains stable during the day. 

If we rule out maintenance as the cause though it may be the case, then it’s possible that there’s some amount of errors on the line, which isn’t resulting in a drop. 

From the GEA test above, you can see there’s ‘Retransmission Low’ which is a setting that DLM has applied to your connection. This is basically a form of error correction, so having this on suggests that there’s some amount of errors that DLM is combatting.