I thought I would post my question here as there seem to be a lot of knowledgeable folk around.
Apologies for the poor title. I couldn't think of anything suitable so please feel free to edit it.
I recently had BT infinity installed and I am seeing a few things that concern me. It looks like there is quite a bit of noise on the line according to the HG612 stats, and as a result I am seeing a high level of interleaving applied to the line.
For the first week or so my speed was hovering around 76Mb, and 20Mb upload. The connection itself was functioning completely fine. I did notice on day one that there were quite a few CRC errors appearing. I think it was on day 2 that interleaving was applied to the line, which remains on the line to this day. The level of interleaving seems to have increased a lot since then. The speeds are now a lot less, and the level of interleaving is now at:. Delay: Downstream:9, Upstream:6. D: Downstream: 1723, Upload: 551.
The number of FEC's don't seem to have really reduced though in this time, although interleaving has been increasing progressively.
When the engineer came around recently and plugged in his JDSU, he advised that the max rate that my is was capable of was showing as about 74Mb , and that my actual rate was around 60Mb. This made me wonder, as according to the HG612 stats, the max rate that the line should be capable of is displayed as 93Mb.
1) Is there any reason for the difference between the maximum rate reading on the JDSU compared to the max rate figure on the HG612?
For the first day, the line seemed stable enough with no disconnections (and was fine for daily use anyway); and as I didn't have any additional latency on the line, everything felt a little snappier I think. For the first week or so, the actual speed still remained at about 74/75Mb. It was only the last few days that the speed seems to have also dropped dramatically also.
2) I would much prefer to have a slower downstream speed, and for there to be no interleaving on the line, but this doesn't seem to be possible. It seems that instead, a heavy level of interleaving is being applied by the DLM, coupled with a reduction in line speeds, but with no noticeable difference in the number errors being reported. Is there any chance of DLM noticing that the caps on speeds and interleaving aren't actually reducing the number of errors, and so will relent, and restore original speed with interleaving off?
Also..
3) Does anyone know why there is such a big difference between the max rate figure in the HG612 stats and my actual sync speed. Max rate in HG612 stats: 93564. Actual: 48703. Surely if my line is (theoretically) capable of much higher speeds, shouldn't I be seeing a much higher actual speed than I am?
Hope I have explained myself well enough. The errors don't seem to be coming in ever second, but maybe every so many minutes a whole load of errors will appear. All Openreach line tests come back as OK.
Here are the HG612 stats:
xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 2
Max: Upstream rate = 27164 Kbps, Downstream rate = 93564 Kbps
Path: 0, Upstream rate = 14996 Kbps, Downstream rate = 48703 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): 13.6 10.9
Attn(dB): 0.0 0.0
Pwr(dBm): 13.6 6.8
VDSL2 framing
Path 0
B: 31 21
M: 1 1
T: 64 64
R: 16 10
S: 0.0209 0.0466
L: 18371 5498
D: 1723 551
I: 48 32
N: 48 32
Counters
Path 0
OHF: 34510549 1275770
OHFErr: 5 0
RS: 2453252362 3087014
RSCorr: 128896 26406
RSUnCorr: 137 0
Path 0
HEC: 26 0
OCD: 0 0
LCD: 0 0
Total Cells: 1127578080 0
Data Cells: 15721732 0
Drop Cells: 0
Bit Errors: 0 0
ES: 7 0
SES: 5 0
UAS: 39 39
AS: 57932
Path 0
INP: 6.00 4.00
PER: 1.67 5.95
delay: 9.00 6.00
OR: 95.68 64.42
Bitswap: 168 49
Total time = 22 hours 30 min 19 sec
FEC: 228061 42165
CRC: 3464 0
ES: 7 0
SES: 5 0
UAS: 39 39
LOS: 5 0
LOF: 5 0
Latest 15 minutes time = 19 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: 2987 2
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Latest 1 day time = 22 hours 30 min 19 sec
FEC: 228061 42165
CRC: 3464 0
ES: 7 0
SES: 5 0
UAS: 39 39
LOS: 5 0
LOF: 5 0
Previous 1 day time = 0 sec
FEC: 0 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Since Link time = 16 hours 5 min 31 sec
FEC: 128896 26406
CRC: 5 0
ES: 1 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
#
Edited by deleted (Fri 14-Jun-13 21:10:21)



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