I am really not that bothered with the results of throughput speed tests and very rarely perform one. If I check anything, it will be the xDSL synchronisation speed.
Here follows the output generated by an "
xdslctl info --show" command for my circuit --
> xdslctl info --show
xdslctl: ADSL driver and PHY status
Status: Showtime
Last Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 16174 Kbps, Downstream rate = 43845 Kbps
Bearer: 0, Upstream rate = 9997 Kbps, Downstream rate = 40000 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode(0x0)
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 7.3 9.1
Attn(dB): 16.0 0.0
Pwr(dBm): 13.3 6.9
VDSL2 framing
Bearer 0
MSGc: -6 43
B: 178 31
M: 1 1
T: 0 64
R: 12 2
S: 0.0000 0.1017
L: 10727 2675
D: 16 1
I: 191 34
N: 191 34
Q: 16 0
V: 2 0
RxQueue: 21 0
TxQueue: 7 0
G.INP Framing: 18 0
G.INP lookback: 7 0
RRC bits: 0 24
Bearer 1
MSGc: 90 -6
B: 0 0
M: 2 0
T: 2 0
R: 16 0
S: 10.6667 0.0000
L: 24 0
D: 1 0
I: 32 0
N: 32 0
Q: 0 0
V: 0 0
RxQueue: 0 0
TxQueue: 0 0
G.INP Framing: 0 0
G.INP lookback: 0 0
RRC bits: 0 0
Counters
Bearer 0
OHF: 0 789893
OHFErr: 0 79
RS: 720723632 187496
RSCorr: 311 277
RSUnCorr: 0 0
Bearer 1
OHF: 1604171 0
OHFErr: 0 0
RS: 9624654 0
RSCorr: 0 0
RSUnCorr: 0 0
Retransmit Counters
rtx_tx: 6189 0
rtx_c: 3 0
rtx_uc: 0 0
G.INP Counters
LEFTRS: 0 0
minEFTR: 39991 0
errFreeBits: 15717867 0
Bearer 0
HEC: 0 0
OCD: 0 0
LCD: 0 0
Total Cells: 1982066721 0
Data Cells: 10916976 0
Drop Cells: 0
Bit Errors: 0 0
Bearer 1
HEC: 0 0
OCD: 0 0
LCD: 0 0
Total Cells: 0 0
Data Cells: 0 0
Drop Cells: 0
Bit Errors: 0 0
ES: 0 77
SES: 0 0
UAS: 23 23
AS: 25772
Bearer 0
INP: 45.00 0.00
INPRein: 0.00 0.00
delay: 0 0
PER: 0.00 11.43
OR: 0.01 34.28
AgR: 40055.74 10031.40
Bearer 1
INP: 2.50 0.00
INPRein: 2.50 0.00
delay: 0 0
PER: 16.06 0.01
OR: 47.81 0.01
AgR: 47.81 0.01
Bitswap: 471/471 77/77
>
As can be seen, it is a VDSL2 service provisioned using the Openreach 40/10 Mbps product. The circuit is synchronised at 40.0/9.9 Mbps (i.e. its maximum) and there is SNRM to spare.
Our friend at "The Weaving Shed" introduced me to A&A's
LibreSpeed tester and, being curious, I tried it out. The result can be seen in the image, attached below.
How is it possible that I achieve a downstream throughput speed equal to the circuit's synchronisation speed?
Am I, therefore, supposed to believe that the writer of that tool does not understand even the basic principals of xDSL technology?