Infinity 2 Sudden Speed Drop

I've been on Infinity 2 (80/20) pretty much since it was released and always enjoyed an IP profile in the high 70's. However over the last few weeks this has seemed to take a tanking and is now in the mid 30's. I've posted some stats below and was wondering if anyone can shed some light.

Is it just a case of waiting and hoping the DLM will release the line eventually?
http://img27.imageshack.us/img27/2486/zlmx.png

I would suggest contacting your ISP, the modem clearly shows an attainable speed of 86mbps, so you should be getting near full speed. But the modem is only synced at 38 Mbps, for whatever reason.

Perhaps run the BT diagnostic speed test first, and see what that says.

Edited by R0NSKI (Mon 19-Aug-13 13:45:11)

What units are the uptime measured in? If that is seconds, then modem has been connected at this speed for a long time, so a restart to see if it improves would be the best bet

366773 seconds >>> ~102 hours or just over 4 days which is not long. However, the counter does cycle round when it reaches 999999 or 9999999 (which would be 120 days) - I have seen it happen but cannot remember which.

In reply to a post by mp90:

I've been on Infinity 2 (80/20) pretty much since it was released and always enjoyed an IP profile in the high 70's. However over the last few weeks this has seemed to take a tanking and is now in the mid 30's. I've posted some stats below and was wondering if anyone can shed some light.

Is it just a case of waiting and hoping the DLM will release the line eventually?
http://img27.imageshack.us/img27/2486/zlmx.png

Do you have a BQM set up? I'm wondering what your latency looks like.

http://www.thinkbroadband.com/ping

Edited by Andrue (Mon 19-Aug-13 15:31:35)

The last reboot was by myself on Friday so the uptime makes sense! Rebooted to see if it made a difference and obviously it didn't so I haven't touched it since.

Should say that the last time I checked my Attainable rate it was showing a figure nearer to 100Meg! My engineer commented during install that my line is very short from the cabinet.

Will set up a BQM and see how I get on!

login to telnet and get the advanced stats.

you are defenitly interleaved on the downstream, not so sure on the upstream, but the fact your upstream isnt a 20000 sync as well shows something is up on that also.

very bizzare situation.

Here's the stats from telnet.

# xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 2
Max: Upstream rate = 45215 Kbps, Downstream rate = 86196 Kbps
Path: 0, Upstream rate = 18988 Kbps, Downstream rate = 38070 Kbps

Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 14.5 15.4
Attn(dB): 0.0 0.0
Pwr(dBm): 12.6 6.8
VDSL2 framing
Path 0
B: 24 24
M: 1 1
T: 64 64
R: 16 16
S: 0.0209 0.0419
L: 15699 7835
D: 1963 490
I: 41 41
N: 41 41
Counters
Path 0
OHF: 10392989 1033942
OHFErr: 174 775
RS: 3990907310 2577676
RSCorr: 200028 1209205
RSUnCorr: 23802 0

Path 0
HEC: 2469 0
OCD: 0 0
LCD: 0 0
Total Cells: 1531908769 0
Data Cells: 25311110 0
Drop Cells: 0
Bit Errors: 0 0

ES: 179 408
SES: 19 189
UAS: 52 52
AS: 20929

Path 0
INP: 8.00 4.00
PER: 2.00 4.01
delay: 10.00 5.00
OR: 71.79 47.77

Bitswap: 0 235

Total time = 1 days 4 hours 49 min 35 sec
FEC: 1217920 4474485
CRC: 10484 3619
ES: 179 408
SES: 19 189
UAS: 52 52
LOS: 17 0
LOF: 16 0
Latest 15 minutes time = 4 min 35 sec
FEC: 0 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 3242 31998
CRC: 6 7
ES: 1 10
SES: 0 9
UAS: 0 0
LOS: 0 0
LOF: 0 0
Latest 1 day time = 4 hours 49 min 35 sec
FEC: 162695 980395
CRC: 138 569
ES: 27 64
SES: 0 25
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 1 day time = 24 hours 0 sec
FEC: 183452 757070
CRC: 2806 730
ES: 30 60
SES: 5 17
UAS: 17 17
LOS: 4 0
LOF: 5 0
Since Link time = 5 hours 48 min 49 sec
FEC: 200028 1209205
CRC: 174 775
ES: 34 88
SES: 0 34
UAS: 0 0
LOS: 0 0
LOF: 0 0

Also the BT Performance Test

Download speedachieved during the test was - 35.93 Mbps
For your connection, the acceptable range of speedsis 16 Mbps-36.85 Mbps .
Additional Information:
IP Profile for your line is - 36.85 Mbps
Upload speed achieved during the test was - 14.91Mbps
Additional Information:
Upstream Rate IP profile on your line is - 20 Mbps

ok you need someone like ronski to look at them but to me looks like interleaving both ways and it seems at an extreme level to the point its wiped huge amounts of sync speed off.

you had large amounts of instability lately?

in fact it looks like you getting interrment bursts of noise.

last 15 mins 0 FEC/CRC but last 5 hours over a million FEC on the upstream.

start graphing it.

Edited by Chrysalis (Mon 19-Aug-13 19:10:52)

You've certainly got high levels of interleaving, both down and up, but I wouldn't have thought it could halve your speed.

Unfortunately I'm not very good at interpreting the stats.

It would be best to download this monitoring program and run it 24 hours a day and see what graphs it produces, then upload them somewhere so others can take a look.

http://forums.thinkbroadband.com/fibre/f/4255736-hg6...

http://www.freewarefiles.com/HG612-Modem-Stats_progr...

If you're not running windows then I think there may other programs for Linux, not sure about Apple though.

Doesn't a drop in speed that large also constitute a fault?

Probably a red herring but have you been doing much torrenting lately? Reason I ask is that I'm on a 40/2 product which is normally stable at 38meg but a couple of times this year after a very heavy P2P session my speed fell with a firm ceiling at 24meg and remained stuck in that band for weeks. I never got to the bottom of it (don't do enough torrenting to test the theory) the two things are probably unconnected, but thought I'd mention it

http://www.thinkbroadband.com/ping/share/f32c7e10872...
Looking at my BQM graph there's definitely something strange going on. I have never had average latency as high as that when I've ever ran a BQM before.

Think it might be time to try and raise a fault with BT, any tips on suffering that

BT wont care about the latency, to them a high interleaving depth is not a fault in itself.

However if the speed drop is recent, judging by your attainable speed its quite possible you have hit openreach's 25% lost speed in 14 days rule which should at least merit a engineer visit.

Just wondering if anyone can take a look at these graphs. Try as I might to understand I don't really know what I'm looking for

https://www.dropbox.com/s/uiyf2a93mmw3vfm/line_stats...

Your Hlog graph exhibits classic symptoms (a 'V' shape) of a bridged tap or star wiring that is probably affecting your sync speed in a big way when compared against Attainable Rate AKA Max :

Your QLN graph suggests that you don't have the quietest of connections, the closer to -140 dBm, the quieter the line.

Your very high Interleaving depths of 1963 / 490 are another symptom.

Your high SNRM margins suggest that your connection SHOULD be capable of a lot closer to 80 / 20 sync speeds.



There's every possibility/probability that the bridged tap/star wiring is somewhere within your property.

Curing that may well cure everything else.

Edited by deleted (Thu 22-Aug-13 17:38:51)