Unreliable ADSL2+ Connection

[#1]

The Plusnet Helpdesk called while Openreach were performing their initial tests, said they would call back - but haven't.

Not sure what these entries on the open question mean:

Summary

Engineer at the site when called this si the current service level.

Will await engineer notes and then check later to update customer

May need time to monitor the service

Kind regards,
[Name]

[Name] - CSC Analyst

12:49pm, Friday 18 Dec 2020

The Question 206678774 has been released from hold and sent back to BOT - DSL Logged Faults - Post SFI

[Name] - CSC Analyst

12:50pm, Friday 18 Dec 2020

Dear Mr C,
This Question is now on hold until Friday 25th December at 1:00pm.
Kind regards,
[Name]

I will be just about to sit down our Christmas lunch at that time...

Regards,

Alistair

[#2]

The connection has been ok overnight and so far today. We have even had incoming phone calls without losing the connection.

Plusnet Staff:

I am still waiting on a line reset.

@jab1  and @Townman :

From what I have seen, the first line Openreach technicians only have test kit that gives a binary pass/fail result; the Senior / Multi-Discipline guys have more advanced kit that display alphanumeric results, and so are able to apply intelligence and judgement to any marginal passes. At less than 500m line-length to the exchange it was not acceptable, but it might be all that was possible at my parent's house some five miles by road from their exchange.

Regards,

Alistair

[#3]

Looking back...

---

@archerry wrote:

It was stated that a 'lift-and-shift' would not be granted if requested as the frame was giving 22Mb/s download.

---

... but at the frame it should be 24mbps ... those stats suggest that 8% of the signal is being lost within the exchange.

IIRC I have had a L&S done where it was 21mbps on the frame.

"I will be just about to sit down our Christmas lunch at that time..."

Someone in Plusnet will still be busy supporting customers at that time!

[#4]

Plusnet staff:

Please reset this line.

If the physical connection to the exchange is fixed then it should be capable of running stably on the Fastpath setting.

Extract from modem/router 'Helpdesk' page:

1. Product name: Plusnet Hub
4. Board version: Plusnet Hub One
5. DSL uptime: 2 days, 17:33:46
6. Data rate: 888 / 17337
7. Maximum data rate: 888 / 17492
8. Noise margin: 11.6 / 15.1
9. Line attenuation: 5.8 / 12.1
10. Signal attenuation: 5.8 / 10.8
11. Data sent/received: 6.8 GB / 125.6 GB
25. Latency type: Interleaved

Regards,

Alistair

[#5]

The Plusnet Helpdesk phoned earlier today to say that they had read the Openreach report, and were about to reset the connection - which they did.
Instead of rebooting the Plusnet Hub One after the prescribed four hours, I re-inserted my favoured modem/router.
The connection was stable for the last week with interleaving after the 'pair change' so we will see how it goes this week on Fastpath, and I will report back in a few days time.
In the meantime, thanks for your help and advice.

DSL Status
Line State: UP [0x0]
Line Mode: G.992.5 (ADSL2+)
Line Uptime: 3m 56s
Annex: A
Profile: -
Data Rate: 23.253 Mb/s / 1.087 Mb/s
Max. Attainable Data Rate (ATTNDR): 23.312 Mb/s / 1.076 Mb/s
Latency: 0.25 ms / 0.25 ms
Line Attenuation (LATN): 12.7 dB / 5.7 dB
Signal Attenuation (SATN): 11.6 dB / 5.7 dB
Noise Margin (SNR): 6.3 dB / 6.3 dB
Aggregate Transmit Power (ACTATP): 20.0 dB / 9.9 dB
Forward Error Correction Seconds (FECS): 0 / 0
Errored seconds (ES): 0 / 0
Severely Errored Seconds (SES): 0 / 0
Loss of Signal Seconds (LOSS): 0 / 1
Unavailable Seconds (UAS): 67 / 67
Header Error Code Errors (HEC): 0 / 7
Non Pre-emptive CRC errors (CRC_P): 0 / 0
Pre-emptive CRC errors (CRCP_P): 0 / 0
ATU-C System Vendor ID: Infineon 113.200
Power Management Mode: L0 - Synchronized

Regards,
Alistair

[#6]

Looking good, Alistair.👍 Shout up as soon as you spot anything strange.

[#7]

Indeed those stats look very good.

[#8]

After about 12 days since the connection was reset, it has been reasonably stable with just one (exchange caused) disconnect/reboot. Below is the current modem/router DSL Status:

Line State: UP [0x0]
Line Mode: G.992.5 (ADSL2+)
Line Uptime: 6d 10h 0m 14s
Annex: A
Profile: -
Data Rate: 23.108 Mb/s / 1.107 Mb/s
Max. Attainable Data Rate (ATTNDR): 23.288 Mb/s / 1.104 Mb/s
Latency: 0.25 ms / 0.25 ms
Line Attenuation (LATN): 12.7 dB / 5.8 dB
Signal Attenuation (SATN): 11.6 dB / 5.8 dB
Noise Margin (SNR): 5.7 dB / 6.4 dB
Aggregate Transmit Power (ACTATP): 20.1 dB / 9.9 dB
Forward Error Correction Seconds (FECS): 0 / 0
Errored seconds (ES): 212 / 12
Severely Errored Seconds (SES): 71 / 0
Loss of Signal Seconds (LOSS): 0 / 1
Unavailable Seconds (UAS): 68 / 68
Header Error Code Errors (HEC): 904 / 15
Non Pre-emptive CRC errors (CRC_P): 0 / 0
Pre-emptive CRC errors (CRCP_P): 0 / 0
ATU-C System Vendor ID: Infineon 113.200
Power Management Mode: L0 - Synchronized

Is the large difference between the downstream and upstream line/signal attenuations significant? Should I be concerned about the HEC Errors?

I am looking forward to not having to monitor my connection.

Regards,
Alistair

[#9]

Morning, Alistair.  Ignore the difference in attenuation - my differences are similar and have never caused a problem. Can't reliably answer the HEC question - think that's one for @Townman .

[#10]

Good morning Alistair,

What a difference a good engineer and a line fix makes!!  By the look of things, this line is now performing better than it has ever done?

Up / down attenuation differences are fully to be expected.  The attenuation figure is not an absolute, but a function of the signal frequency.  Though one might expect that the impedance of the circuit is the same in both directs, the frequency of the up and down signals is markedly different, hence so are the signal attenuation figures.

23+mbps is a shade better then the previously reported 22mbps at the frame.  The error counts are fairly low, so I would not be bothered by them.

I recommend leaving everything well alone now and see how long the connection remains up without a break.  I've seen xDSL up for over 100 days on multiple occasions, PPP being a somewhat different matter consequential to exchange broadband maintenance activity.

If you are so inclined, you might now look at data speed tests to monitor throughput, but remember that these are not reliable measurement systems, being very dependent on the performance of the systems at both ends of the link.

[#11]

@jab1 

@Townman 

Thank you for your help.

We have got there in the end.

I look forward to long up times - as it was prior to the upgrade to ADSL2+.

Is there a way to mark this thread resolved?

Regards,

Alistair

[#12]

A topic is never marked as "fixed" but rather a post which brought about resolution of the problem might be marked "this fixed my issue".  s the originator of the topic, you can choose which post you feel either fixed your issue or brought about action which lead to it being fixed.  Just click the big green button on the relevant post.

Looking back over your history here, I doubt that this issue was brought about by the upgrade to ADSL2+ (for 17mbps you were already on ADSL2+), but more likely by a deterioration of the exchange line.  If I have understood your feedback on the BTOR visit clearly then there appears to be a fault in one of the two circuit bundles back to the exchange.

[#13]

@Townman 

As you say, the upgrade to ADSL2+ in late 2011/early 2012 did not cause the issue, it merely revealed it. I had a great deal of 'fun' at the time trying to get it fixed. A combination of expensive modem/router and interleaved connection mostly held it together for several years.

With the first line Openreach technicians only having test kit that gives a 'pass/fail' result, they would not recognise the underlying issue with the twisted pairs connecting to the exchange.

Again, thanks to all who helped.

Regards,

Alistair

[#14]

... it is not really the done thing to mark one's own post as "this fixed it for me" (and gain the associated kudos points for it) but in the absence of visible staff contributions here identifying their specific action which brought about the resolution, it is rather difficult to give a more appropriate party recognition for their contribution to the resolution.

@PaulScott @Gandalf