Power cut, and loss of sync??

So I suffered a power cut last night, between 4pm and 6pm, and seem to have lost sync speed. I assume the weather is the reason. Just wondered if any ideas here?

Modem is a Huawei HG612, but is probably about 5 years old, and I wonder if it needs replacing?

Data from 7th Dec - how things have been for months:

Direction			Downstream	Upstream
Line attenuation (dB):  	21.1		0.0
Signal attenuation (dB):	Not monitored		
Connection speed (kbps):	61662		8911
SNR margin (dB):        	3.3		6.0
Power (dBm):            	12.9		6.1
Interleave depth:       	4		1
INP:                    	52.00		0
G.INP:                  	Enabled		Not enabled
Vectoring status:       	5 (VECT_UNCONFIGURED)		

RSCorr/RS (%):          	0.8386		0.1593
RSUnCorr/RS (%):        	0.0000		0.0000
ES/hour:                	0		231

It looks as if I dropped sync and lost speed on the 11th, but my PC isn't on enough to capture the data. I only noticed after the power came on last night.

Right now stats (15th Dec at 15:25):

Direction			Downstream	Upstream
Line attenuation (dB):  	21.1		0.0
Signal attenuation (dB):	Not monitored		
Connection speed (kbps):	46222		7305
SNR margin (dB):        	3.1		6.3
Power (dBm):            	13.1		6.7
Interleave depth:       	4		1
INP:                    	52.00		0
G.INP:                  	Enabled		Not enabled
Vectoring status:       	5 (VECT_UNCONFIGURED)		

RSCorr/RS (%):          	0.0237		0.0026
RSUnCorr/RS (%):        	0.0000		0.0000
ES/hour:                	1.34		27.8

This morning about 10am I did a (daylight) forced reboot, but no change.

Is there anything I can check or just wait until the cold and rain stop and hope it goes back up?

Edited by jchamier (Sat 15-Dec-18 15:32:03)

Blimey, that is a drop in speed (especially the DS but also US). Output power has changed significantly, which would suggest a line fault. Do you have a phone you could try? Do you have a dial tone? Is the line noisy? Line attenuation hasn't changed, which I would expect to have, but it doesn't always when there's a fault. I was thinking it could be a new crosstalker, but the SNRM on the first stats would have dropped if that was the case. The US ES/hour on the first stats is very high, which would also suggest something isn't right (the loss of sync speed on the resync has meant these have dropped to a more normal level but are still high).

The HG612 is fairly outdated, so I would recommend replacing it with a more modern device ASAP, but I doubt the issue is due to that.

Edited by deleted (Sat 15-Dec-18 16:21:27)

Thanks. The phone handset I have seems to have developed a fault in the cable from the handset to base, which makes a QLT harder than it should be (!). I'll get a replacement tomorrow. The line is from HG612 to a Mk2 openreach faceplate - the phone is also connected here.

The first stats was over an uptime of 15 days, 14 hours. The second stats is just 5 hours.

I will go to the Hardware forum to discuss modem choices, as my router is ethernet WAN only.

unless you see excess SNRM then is little point in doing a reboot, because if the unused SNR isnt there, it wont jump up.

Do you have any plots of things like bitloading and QLN?

Edited by Chrysalis (Fri 28-Dec-18 16:49:54)

In reply to a post by Chrysalis:

unless you see excess SNRM then is little point in doing a reboot, because if the unused SNR isnt there, it wont jump up.

Sadly thought as much, but was hoping it was down to rain, maybe xmas lights. More likely decaying openreach wiring in this block of flats.

Do you have any plots of things like bitloading and QLN?

Yes, when I have the PC on ( a lot of the time ), then DSLstats is running.

Here you go - if this works, stats from today (29th) and from 7th Dec with the higher sync.
https://1drv.ms/f/s!AoB3AikEMXqSgecGKWiyb5qwo3JSrg

Let me know if any other graphs are useful.
Many thanks!

Edited by jchamier (Sat 29-Dec-18 00:43:22)

Update, now its January.

I bought a ZyXEL VMG1312-B10A which arrived yesterday. Updated the firmware and did some configuration before plugging into the phone line. New PSU and new DSL cable plugged into the Openreach faceplate filter Mk2 that is on the master socket.

Stats:

DSLAM type / SW version:	BDCM:0xa48c (164.140) / v0xa48c
Modem/router firmware:  	AnnexA version - A2pv6F039v.d26a
DSL mode:               	VDSL2 Profile 17a
Status:                 	Showtime
Uptime:                  	2 hours 1 min 39 sec
			
				Downstream	Upstream
Line attenuation (dB):  	21.0		0.0
Signal attenuation (dB):	Not monitored		
Connection speed (kbps):	54074		6321
SNR margin (dB):        	3.3		6.2
Power (dBm):            	13.0		5.9
Interleave depth:       	4		1
INP:                    	52.00		0
G.INP:                  	Enabled		Not enabled
Vectoring status:       	5 (VECT_UNCONFIGURED)		

RSCorr/RS (%):          	0.0259		0.0107
RSUnCorr/RS (%):        	0.0000		0.0000
ES/hour:                	0.23		5.85

Edited by jchamier (Sun 06-Jan-19 13:24:43)

Hi

If there has been a wide area power cut then for VDSL it's a complete reshuffle of a deck of cards when power is restored. You have dozens of modems all trying to sync back at the same time once the power is back on, some will get there first, see little cross-talk and negotiate higher power levels and get a better sync, this then means more cross-talk for other lines that might not have had so much before, or they get their power restricted in order to be neighbour friendly.

It might be your line cross-talks badly with another subscriber, they may have always sacrificed speed in favour of your line because you were there first, now it's the other way around.

There isn't a lot you can do really, hopefully over time the equilibrium you had before is slowly restored, but then it may just stick as the new norm.

Regards

Phil

Edited by deleted (Mon 07-Jan-19 10:21:14)

Thanks that�s the best idea so far; I was just lucky before !