DLM reset request (ADSL2+)

[#1]

@Mardler 

"We're about 0.7 of a mile from the exchange."

Just a thought, but how are you measuring that distance?

Is it the shortest distance by road from your house to the exchange, or do you have knowledge of the Openreach network topology? (ie from working for or speaking to Openreach, or being a rural area, are all the cabes clearly visible above ground on poles?

As an example, at a previous house, we were also much less than a mile from the exchange, by road. However, I discovered that to get to us, the cable from the exchange went past our house to the cabinet over 400 metres further up the road. The cable from the cabinet to the pole across the road from us added another 400 metres or so.

The net effect being that "our" telephone pair back to the exchange, (we also had ADSL then), was over twice the "direct path" length.

When that was taken in to account, the speeds we were getting made a lot more sense!

.

[#2]

Feel free to ignore, but 'mains interference at midnight' suggests two somewhat obscure things to me.

1 - Someone has a 'whole house storage heater' on the same phase circuit as you, and it turns on at midnight and could (as experience) bring the mains down out of limits.

If **AND ONLY IF** you are confident with handling mains SAFELY, try measuring the voltage during 'problems'.

My parents observed input at 205V - out of spec.  Reported to SSE and a bigger transformer was installed - although it is not happy with 100A hanging on just one phase even now.  You can hear it 'singing' in the night.

2 - Recent auroral activity ?  A long overhead line might be getting bothered.

Bill

[#3]

@Mardler 

In order tto get to the base performance of your line you need to stop your manual adjustment of the SNR and rebooting of the hub of your choice. Without this base information it is impossible for Plusnet/Openreach to remotely determine accurately how your line is performing.

Unfortunately this may require you to accept poor performance for a week or so. It might also be instructive to run a DSL monitoring programme, see https://kitz.co.uk/routers/monitor_linestats.htm

[#4]

About 90 minutes ago I reset the router.

Target SNRM was 4 as it has been for the last 2 or 3 years with excellent sync and a stable connection up for months apart from occasions like this.

The data is as follows with Wednesday first (as indicative of what we have had for years with the Billion router) and today's figures in brackets:-

Actual SNRM: 6.4 (7.1)

Attenuation: 16 (17.5)

Attainable rate: 21220 (14640)

Sync: 20379 (13123)

The degradation is obvious.

Of particular note is the increase in attenuation. This is external and indicates an exchange or line fault as before.

NB. Before I reconnected the connection had been up for 17hrs (with a poor sync of 11179 admittedly) without a disconnect.

Thanks for your input, guys. Here are my responses:-

Mr_P: the distance to the exchange is measurable by following the telegraph poles in the car; the figure was also given to me by Openreach years ago.

Wow: interesting thought however I am fairly sure no-one here uses such devices. The effect of the solar radiation, or lack of it, should be observable tonight.

Years ago we suffered from out of spec low voltage which damaged equipment. Eventually a new transformer was installed a few feet from the house which gives c.235V.

Yup, recent solar radiation might be a culprit, it was a strong one (also a CME last Thursday).

Baldrick: I have done this. Sync dropped to c.9.5mbps. Please note that the tweaked SNR (from 6db to 4) has been used for years with excellent results including a near bomb proof connection apart from these occasional bouts. At one point I dropped it to 2 still with a 100% stable connection. I draw your attention to the attenuation.

Having had several bouts of similar behaviour over the years I am familiar with BT/Openreach requirements.

Thanks for the link. I think it runs on a computer not a tablet so whether a clunky old Windows laptop will run it who knows.

Finally, we can live with download speeds of 13123 (wi-fi 11.2mbps) though the near 20 we had become used to was noticeably better in practice. The frequent disconnects are another matter entirely.

[#5]

Attainable rate now falling.

Tried setting SNRM back to standard (6db) and sync was 11539.

SNRM 4 (6-2) was 12779 (13123 earlier as above).

SNRM 3 (6-3) was 13651.

Attainable rate is nowhere near Wednesday's 21220 (SNRM set to 4 giving an actual 6.4).

Something is definitely wrong.

[#6]

TM: either you have not read what I have said or, as in the past, you are deliberately being unhelpful.

So, let me state thevfacts clearly: on Wednesday afternoon the sync was 20379 very similar to the last few years when the connection was stable apart from a few events like now. I have clearly stated that I have also set the router to its standard setting which is the widely accepted 6db SNRM except that the reported actual SNRM is anything from 9 to 12 (the PN router is identical).

Of course the line should be better than this and it has been, that is the point I am trying to get across to you.

Your "trying to bend light" insult is noted.

[#7]

If you want help please STOP adjusting the SNRM in the router. Let the DLM manage the service. If the speed is low then that’s because there is a fault … so raise a fault report.

Telling us what it was last week, month, year is just that - history. Lines deteriorate, acquire faults and perform differently. If your line really is 0.7km you should get 24mbps without breaking sweat.

The fact that you are getting less means the line is (electrically) longer than you think it is … or it has a fault. To help you, we need two baselines please - stop gaming the SNRM and share the line attenuation figure reported by the router.

Edit: posts crossed. If you think this is unhelpful … by all means ignore the advice and sort it yourself.

[#8]

Sync is falling with every disconnect. 

I will try to keep the d/l speed sufficient for streaming YT this evening then reset target SNRM to standard and try to raise a ticket with PN tomorrow.

ITM, I cannot repeat enough that the Billion router is excellent (it does not "attempt to bend light"!), it maintains a high sync for months and is only interrupted by faults like this. Oh and the Technicolor 582 was also syncing at c.11 on Wednesday morning.

[#9]

The Billion router is excellent and can do a great job of getting the best out of a marginal line. However you do not want a router gaming things. If your line really is 0.7km (attenuation circa 10dB) then you should easily see 24mbps without breaking sweat from the most basic of routers. The fact that you do not points to a fault / environmental issue.

Knowing your line attenuation informs what you should get - that’s the first baseline to assess if you do have a fault requiring investigation. Until that baseline is established you are in a circular … it was this then … it’s something else now.

Sync falling every connection points to DLM managing for stability - which creates the dilemma of is the perceived instability arising from a line fault … or you repeatedly bouncing the router.

[#10]

I don't know whether to laugh or cry - there is obviously a fault somewhere - most likely in OpenReach world, so why not just get a fault raised?

I don't know if it makes any difference, but the OP keeps saying a 'line length of 0.7miles, which seems to get translated to 0.7km - that makes a great difference.

The hub/router stats (in unfudged state) would have been very useful at the START of this topic.

[#11]

John,

Doh!!! Line length is usually reported in kms!! 0.7m is circa 1.1km so the attenuation should be circa 17dB delivering 22mbps at a 6dB SNRM.

Gaming the SNRM to 4dB on a perfect line should readily deliver 24mbps.

[#12]

Yep, I know it usually is, but I'm guessing the OP is a bit like me and still works in Imperial - although I'm perfectly happy working metric.

[#13]

Re the distance to the exchange.

Strangely I do work in Imperial but am happy with metric as well.

I looked up the distance. Google maps gave 0.5 miles which is c.800metres. The map gave a slightly longer route than actual so Openreach's 0.7km wasn't far off. 

Whatever, it's well under a mile in old money.

[#14]

OK but what’s the attenuation figure from the router stats?

[#15]

@Townman from a quick check back - somewhere between 16 and 17..5