Normally a solid 76mb down to @55mb with latency issues today

[#1]

Hi,

Ive enjoyed a rock solid connection of 76mb with 15mb upstream, low latency and no packet loss problems until today.

Unfortunately, I now have 50mb-60mb with latency issues.

Any known regional issues?  Any suggestions?

Thanks

teal

[#2]

Also, I notice that hops 2 and 3 of all tracerts time out - is this normal on plusnet infrastructure?

[#3]

Many devices will not respond to pings/tracerts.

Speed tests can also vary, start with the basics, what are your connection speeds - a copy of the Helpdesk Page would be a good place to start - make sure you remove the personal info. 

[#4]

Storms and other weather can add noise on the line. Your signal to noise ratio could be very low. Which router are you using? It may have some stats. Have the same issue you do. My SNR is down to 4.2dbm on downstream. My SNR for upstream is 15dbm, v healthy.

[#5]

Hey,

Thanks for your replies.  Below is the helpdesk page info:

What do you think of the SNR? I dont know the ideal parameters...

1. Product name:	Plusnet Hub
2. Serial number:
3. Firmware version:	Software version 4.7.5.1.83.8.237.2.2 Last updated 13/11/17
4. Board version:	Plusnet Hub One
5. DSL uptime:	0 days, 02:38:19
6. Data rate:	19999 / 78428
7. Maximum data rate:	24914 / 76053
8. Noise margin:	15.4 / 5.4
9. Line attenuation:	21.7 / 16.0
10. Signal attenuation:	21.6 / 16.2
11. Data sent/received:
12. Broadband username:
13. 2.4 GHz Wireless network/SSID:
14. 2.4 GHz Wireless connections:	Disabled
15. 2.4 GHz Wireless security:	WPA2
16. 2.4 GHz Wireless channel:	Automatic (Smart Wireless)
17. 5 GHz Wireless network/SSID:
18. 5 GHz Wireless connections:	Enabled (802.11 a/n/ac (up to 1300 Mb/s))
19. 5 GHz Wireless security:	WPA2
20. 5 GHz Wireless channel:	Automatic (Smart Wireless)
21. Firewall:	Default
22. MAC Address:
23. Modulation:	G.993.2 Annex B
24. Software variant:	AA
25. Boot loader:	1.0.0

Todays Ookla test results:

 PING

22ms

 DOWNLOAD

52.64Mbps

 UPLOAD

15.56Mbps

Normal Ookla results: 

18

75.31

18.88

1 1 ms 1 ms 1 ms dsldevice.lan [192.168.1.254]
2 * * * Request timed out.
3 15 ms 15 ms 16 ms 133.hiper04.sheff.dial.plus.net.uk [195.166.143.133]
4 16 ms 24 ms 16 ms be3-3102.pcn-ir02.plus.net [195.166.143.132]
5 16 ms 16 ms 15 ms 195.99.125.144
6 15 ms 15 ms 16 ms peer7-et-0-1-4.telehouse.ukcore.bt.net [109.159.252.94]
7 16 ms 15 ms 15 ms peer5-te0-9-0-32.telehouse.ukcore.bt.net [195.99.126.81]
8 16 ms 16 ms 15 ms 151.101.64.81

-This time tracert only has hop 3 timed out.

Awaiting comments/advice

[#6]

That looks very similar to mine.

The stats give upload/download. You've got enough signal to be able to sync to the exchange connection (DSLAM) which has given you 20Mbps up and 78.5Mbps down.

However, the sync rate isn't the usage rate which you're seeing as 15.56Mbps up and 52.64Mbps down.

[I've updated this for clarity]

Signal to Noise ratio is the key here. Make a note of the following paragraph.

"< 6dB: An SNR of less than 6 dB usually will result in line issues.

7dB - 10dB: This is a decent SNR but doesn't leave much room for variances in line conditions.

11dB - 20dB: Most people who live within a short amount of distance from the street cabinet (less than 1500 feet) will have an SNR within that range.  This will result in little to no sync problems.

20dB - 28dB: Outstanding SNR, you must have the street cabinet as your next door neighbour."

The gap between the signal and the noise on the line is the key. When the line syncs, the network equipment listens the line noise to set the speed. At the time of the sync the SNR is OK so the SNR margin is set low.

The margin shown represents the margin to keep the line under sync. Whilst a higher SNR is good, a lower SNRM is better IF the line is stable and didn't get bursty noise.

I'll explain more in another post after I get a cup of tea.

[#7]

to continue. 

Here are my VDSL line stats. Similar to yours but you have more signal lost attenuation over the line, you could be further away from the street cabinet than I am.



My Asus router also gives additional info.

There are two modes listed, Interleaved and Fastpath. If you have low noise line then it will give you connection without so much checking for noise, Fastpath. My upstream is good hence Fastpath.

My downstream is on a line that is susceptible to noise, so the signal is put into smaller sections or Interleaved. It means that if there is sudden noise on the line then a smaller amount of signal is lost and has to be resent. The problem with this is that you take a speed hit.

Look at Power. In order to get my downstream signal nice and loud against the noise, more power is needed as compared to the quieter upsteam where much less power is needed.

I used to get a nice 72Mbps until we had a storm here and it now bumps between 56 and 66Mbps. The storm didn't come inside the house so I don't believe it's my equipment. I think an external cable has gotten loose somewhere and need replacing.

That's why I've asked for an engineer.

[#8]

@BrainSuperGlue  I don't think your info about signal to noise ratio is correct, actually it is complete nonsense. Firstly modem stats show SNRM values - signal to noise ratio margin which is designed to allow for line variations without losing sync. The normal default value is 6dB and the vast majority of lines work perfectly well with this value. In fact the BT Openreach DLM system (Dynamic Line Management) which controls FTTC line parameters can reduce SNRM to as low as 3dB if a line is stable and showing low error count. This decrease in SNRM can significantly improve the sync speed  and therefore the throughput speed for these lines. Of course on shorter lines the modem is syncing at the maximum 80/20Mbps so the SNRM margin will be higher than the default value.

The fact that the OP's throughput speeds are lower than expected is nothing to do with the SNRM value as you claim. There will be other reasons for the drop in speed.

I think you will be very lucky to get an engineer to look at your problem, you are probably well within the expected speed range for your line.

[#9]

Hi RealAleMadrid,

You're missing my point.

Yes, I agree that the move by Openreach is to bring down the line SNRM to 3dB as they have been testing and migrating over the last year or so. What I'm saying is that for me and apparently for the OP, it appears we have bursty noise on our lines. That when the line gets synced it is reasonably quiet and the line gets given a low SNRM. If the line stayed quiet then countermeasures wouldn't be needed but instead of raising the SNRM and lowering the speed it is upping the sending power, interleaving and lowering the speed. Our lines lines aren't losing sync at the SNRM we have as designed but our lines could be less prone to spiky noise as mine was prior to the storm. 

BSG

[#10]

Hi teal. Sorry to hear you're having connection problems. Our tests aren't finding the cause of that.

Are your devices connecting over WiFi or straight to the router using an ethernet cable?

[#11]

Hi Gandalf,

Thanks for the reply. 

To answer your question, I use a LAN cable for my PC.

The initial problem was on the 1stMarch but in the next day or two, it resolved and returned to normal performance.  I was waiting for the 'help and support page question (169536444) to be updated before closing the query and updating this thread.

But today the problem has returned as is reflected on the speedtests (see attached jpg).  

Is it possible that the engineers testing was done on one of the good days? 2ndMarch - 5th march?

The truth is Im not bothered so much about the reduced bandwidth so much as the problem with gaming.  In games, my characters are running slow, then fast, repeatedly and consistently - Ive never experienced this before, but it seems to corelate with the reduced bandwidth on a speed test.

-teal

[#12]

And since yesterday, it has returned to normal excellent performance.  No gaming lag, no reduced bandwidth.  As the problem happens for  full single days at a time, is it possible its the management or throttling system doing this somehow?

[#13]

Hi teal.

Is it possible that the engineers testing was done on one of the good days? 2ndMarch - 5th march?

Doesn't look like your fault ticket has been picked up yet.

Our tests aren't finding any issues at all...

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	79.3 Mbps
Upstream Speed	20.0 Mbps
Appointment Required	N
Fault Report Advised	N
NTE Power Status	PowerOn
Voice Line Test Result	Pass
Bridge Tap	Not Detected
Radio Frequency Ingress	Not Detected
Repetitive Electrical Impulse Noise	Not Detected
Cross Talk	Not Detected
Estimated Line Length In Metres	496.7
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
Profile Name	0.128M-80M Downstream, Retransmission Low - 0.128M-20M Upstream, Error Protection Off
Time Stamp	2018-02-22T15:15:00

Parameters	MIN	MAX	AVG
Down Stream Line Rate	78.5 Mbps	79.9 Mbps	79.7 Mbps
Up Stream Line Rate	19.9 Mbps	20.0 Mbps	19.9 Mbps
Up Time	805.0 Sec	900.0 Sec	899.7 Sec
Retrains	0.0	1.0	0.0

Current and Last 15 Minute Bin Performance
Parameters	Last Traffic Count(Upto 15 mins)	Current Traffic Count(Upto 15 mins)
Start Time Stamp	2018-03-07T14:32:30Z	2018-03-07T14:47:30Z
Ingress Code Violation	0	0
Egress Code Violation	0	0
Errored Seconds	0	0
Severely Errored Seconds	0	0
Unavailable Seconds	0	0

As the problem happens for  full single days at a time, is it possible its the management or throttling system doing this somehow?

It's unlikely as the dynamic line management shouldn't work in that way.

From the Profile Name above, there's no banding applied either.

Are you able to replicate the problems using a different computer?

[#14]

Are you able to replicate the problems using a different computer?

No, though I can use a speed test on my mobile easily enough next time it happens to verify the reduced performance on the pc bandwidth.  

The only two days the problem happened were: 1st march and 6th march  - so the above tests may not have caught the issues?

I appreciate your help though Gandalf.  Ill be sure to post again as soon as and if it reoccurs.  And Ill use my mobile to wifi speed check alongside the pc; and Ill post some video of the weird effects it has on gaming.

Thanks in the meantime

[#15]

No problems at all. Keep us posted!