Most engineers ever involved? DSL speed issues progressed to line disconnection - Still not solv

[#1]

Just before I log off for the night and leave the office, I've checked the fault report and from what I can make of the engineer notes (Aren't always the easiest to read), line tests pass but the case management team want this further investigated at an exposed section of the line on a road beginning with S and ending in G.

Unfortunately this does mean we need to arrange another engineer visit.

I'll update your ticket shortly with more info including the engineer notes if you're interested in reading them.

[#2]

Two engineers this time, apparently. And... No change. No real significant improvement to "insertion loss" - and still line drops.

[#3]

Okay, so I've been fiddling with scripting, since my router runs OpenWRT and I have a bit of access to stats. I started logging g997sang - which is the first graph. I think this is an inverted SNR margin per tone. As you can see, no real access to higher tones here, since it's a long line. Then tried g997bang which gives bit allocations per tone. Both of these seem to update every 2 seconds or so.

Trying to find out the parameters of this fault and because waterfall visualisation is The New Thing.

[#4]

Did some more scripting.

This is showing the bitloading over time. Bins only go up to 140 here because it's a long line. Rebooted the router at around 10am - the frequencies used increased, but not the overall bits. Really odd unless the line is profiled.

[#5]

And another graph - time period is different, but this shows the SNR per tone over time.

[#6]

Those graphs don't really help much, is your router capable of running DSL stats or any similar program?

[#7]

No. What specifically would help do you think? SNR margin? Connection speed? Estimated line length (which, oddly, varies)...

[#8]

The usual graphs would be a line graph of the SNRM varying over time, and perhaps also graphs of errors (CRC and/or FEC) per sample or per minute, varying over time.

Also, have you tried another modem?

[#9]

Yes, I have tried another modem. 3, in fact. One hub0, one tg582n and another HH5a. Of them all the HH5a seems to get the best connection, but it's marginal differences. 

Thanks, I'll see what I can get logging.

I think I know where FECS is stored, not sure where CRCs are. Will have a dig around dsl_cpe_pipe again.

Interestingly, to me at least, some higher bins have opened up and the bits loaded in some of the lower bins have increased. Just as the sun goes down. Hmmm.

If you've not seen a waterfall before, the colours represent the number of bits which are present in a bin - so how much data the modem believes can fit in a frequency range. "hotter" colours are more data, white is nothing happening at all. Definitely seems to have been a jump and we're now getting a bit better stats...

ATU-C Vendor ID:                          Broadcom 163.167
ATU-C System Vendor ID:                   00,00,30,30,30,30,00,00
Chipset:                                  Lantiq-VRX200 Unknown
Firmware Version:                         5.8.0.11.1.1
API Version:                              4.17.18.6
XTSE Capabilities:                        0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0
Annex:                                    A
Line Mode:                                G.992.5 (ADSL2+)
Profile:
Line State:                               UP [0x801: showtime_tc_sync]
Forward Error Correction Seconds (FECS):  Near: 1320434 / Far: 0
Errored seconds (ES):                     Near: 2510 / Far: 57
Severely Errored Seconds (SES):           Near: 542 / Far: 22
Loss of Signal Seconds (LOSS):            Near: 17 / Far: 11
Unavailable Seconds (UAS):                Near: 430 / Far: 430
Header Error Code Errors (HEC):           Near: 66010 / Far: 1440
Non Pre-emtive CRC errors (CRC_P):        Near: 0 / Far: 0
Pre-emtive CRC errors (CRCP_P):           Near: 0 / Far: 0
Power Management Mode:                    L0 - Synchronized
Latency / Interleave Delay:               Down: Interleave (8.0 ms) / Up: Interleave (6.75 ms)
Data Rate:                                Down: 1.814 Mb/s / Up: 446 Kb/s
Line Attenuation (LATN):                  Down: 66.3dB / Up: 39.3dB
Signal Attenuation (SATN):                Down: 60.7dB / Up: 39.0dB
Noise Margin (SNR):                       Down: 9.3dB / Up: 12.2dB
Aggregate Transmit Power (ACTATP):        Down: 16.7dB / Up: 12.3dB
Max. Attainable Data Rate (ATTNDR):       Down: 2.200 Mb/s / Up: 650 Kb/s
Line Uptime Seconds:                      2093
Line Uptime:                              34m 53s

[#10]

And of course, chutzpah strikes. No sooner do I post this, the modem goes a bit loopy, disconnects and reconnects 5 times in a row or so. Argh.

[#11]

So what are your line expectations on the DSL Checker - try and post the table, but hiding your phone number.

Clearly you are not near the exchange and so you are not going to get a great service, have you explored any other options?

[#12]

Hi Mustrum,

FTTP oD would be great However, this line has previously negotiated up to 2.2-2.5 and stayed stable at that for a couple of weeks (when we moved in) so set high expectations.

Looks like the line drops might be the exchange renegotiating upwards on line improvement rather than anything bad - we gained a couple of bins and strengthened the bottom ones. It hasn't rained here in a few days which may be related.

on Exchange COALBURN is served by Cabinet 2

Featured Products	Downstream Line Rate(Mbps)		Upstream Line Rate(Mbps)		Downstream Range(Mbps)	WBC FTTP Availability Date
FTTP on Demand	330		30		--	Available	--	--
ADSL Products	Downstream Line Rate(Mbps)		Upstream Line Rate(Mbps)		Downstream Range(Mbps)	Availability Date		Left in Jumper
WBC ADSL 2+	Up to 1		--		1 to 3.5	Available	--	--
ADSL Max	Up to 1		--		0.75 to 2.5	Available	--	--
Fixed Rate	0.5		--		--	Available	--	--
Other Offerings						Availability Date
ADSL Multicast	--		--		--	Available	--	--
Premise environment	Status
Bridge Tap	U
VRI	N
NTEFaceplate	N
Last Test Date	11-05-2018

Best Effort Test: -provides background information.

	Download  Speed
	1.01 Mbps

0 Mbps

2 Mbps Max Achievable Speed

 Download speedachieved during the test was - 1.01 Mbps
 For your connection, the acceptable range of speeds is 0.8 Mbps-2 Mbps.
 IP Profile for your line is - 1.56 Mbps

2. Upstream Test: -provides background information.

	Upload Speed
	0.12 Mbps

0 Mbps

0.45 Mbps Max Achievable Speed

Upload speed achieved during the test was - 0.12Mbps
 Additional Information: Upstream Rate IP profile on your line is - 0.45 Mbps

ATU-C Vendor ID:                          Broadcom 163.167
ATU-C System Vendor ID:                   00,00,30,30,30,30,00,00
Chipset:                                  Lantiq-VRX200 Unknown
Firmware Version:                         5.8.0.11.1.1
API Version:                              4.17.18.6
XTSE Capabilities:                        0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0
Annex:                                    A
Line Mode:                                G.992.5 (ADSL2+)
Profile:
Line State:                               UP [0x801: showtime_tc_sync]
Forward Error Correction Seconds (FECS):  Near: 6166057 / Far: 8
Errored seconds (ES):                     Near: 27179 / Far: 114
Severely Errored Seconds (SES):           Near: 3536 / Far: 44
Loss of Signal Seconds (LOSS):            Near: 78 / Far: 22
Unavailable Seconds (UAS):                Near: 1913 / Far: 1910
Header Error Code Errors (HEC):           Near: 524808 / Far: 2902
Non Pre-emtive CRC errors (CRC_P):        Near: 0 / Far: 0
Pre-emtive CRC errors (CRCP_P):           Near: 0 / Far: 0
Power Management Mode:                    L0 - Synchronized
Latency / Interleave Delay:               Down: Interleave (8.0 ms) / Up: Interleave (6.75 ms)
Data Rate:                                Down: 1.817 Mb/s / Up: 446 Kb/s
Line Attenuation (LATN):                  Down: 66.2dB / Up: 39.0dB
Signal Attenuation (SATN):                Down: 59.9dB / Up: 39.0dB
Noise Margin (SNR):                       Down: 9.2dB / Up: 13.1dB
Aggregate Transmit Power (ACTATP):        Down: 16.8dB / Up: 12.3dB
Max. Attainable Data Rate (ATTNDR):       Down: 2.248 Mb/s / Up: 620 Kb/s
Line Uptime Seconds:                      7252
Line Uptime:                              2h 0m 52s

Thanks,

Allan.

[#13]

Hi Allan.

I've escalated this to team manager level.

I'll let you know when I hear back though I suspect we'll need to book another engineer visit.

[#14]

@Gandalf,

Should not 

monitored by the Openreach Multiple Repeats Case Management Team

have negated the need for PN to escalate?  Or have these guys dropped the case now?

[#15]

@Dibblah

This doesn't help your problem at all but CodeLook report FTTC as available for your cabinet. Randomly selecting a couple of post codes and using the OpenReach "When can I get Fibre" website reports the same. Looks like your line is too long even to be mentioned for FTTC on the DSL Checker.

Have you tried your post code in the OR site just in cast there are plans for your area. Probably unlikely given most of the cabinet appears to be FTTC.

https://www.openreach.co.uk/orpg/home/index.do

Brian