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[Tacitus]

Can someone tell me how I can tell if G.INP and vectoring are enabled?  I'm on a Huawei cab and at present am using a Broadcom based modem and wondered what to look for in the stats.  I've pasted a sample below - as you can tell I'm on a 40Mbps service.  It all looks OK to me - I'm about 400m from the Cabinet.

Whilst posting, I've never really understood the significance of FECs and CRCs so if someone could give me an idiot's guide I'd be grateful 

============================================================================
    VDSL Training Status:   Showtime
                    Mode:   VDSL2 Annex B
            VDSL Profile:   Profile 17a
            Traffic Type:   PTM Mode
             Link Uptime:   37 days: 21 hours: 38 minutes
============================================================================
       VDSL Port Details       Upstream         Downstream
               Line Rate:     10.057 Mbps       39.999 Mbps
    Actual Net Data Rate:      9.999 Mbps       40.000 Mbps
          Trellis Coding:         ON                ON
              SNR Margin:        8.2 dB           12.3 dB
            Actual Delay:          0 ms              0 ms
          Transmit Power:        7.5 dBm          14.0 dBm
           Receive Power:       -6.4 dBm          -5.2 dBm
              Actual INP:        0.0 symbols      47.0 symbols
       Total Attenuation:       14.0 dB           19.2 dB
Attainable Net Data Rate:     12.308 Mbps       58.524 Mbps
============================================================================
      VDSL Band Status    U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB):  6.9    28.5    42.0     N/A    13.8    33.8    54.0   
Signal Attenuation(dB):  6.9    28.4    42.3     N/A    16.9    33.4    54.0   
        SNR Margin(dB):  8.1     8.2     8.2     N/A    12.3    12.3    12.3   
   Transmit Power(dBm):  0.4   -14.7     6.6     N/A    11.6     8.1     6.0   
============================================================================

            VDSL Counters

           Downstream        Upstream
Since Link time = 38 min 21 sec
FEC:      932149      44173
CRC:      31      2886
ES:      26      2550
SES:      0      9
UAS:      0      0
LOS:      0      0
LOF:      0      0
LOM:      0      0

Latest 15 minutes time = 8 min 50 sec
FEC:      124      0
CRC:      0      0
ES:      0      0
SES:      0      0
UAS:      0      0
LOS:      0      0
LOF:      0      0
LOM:      0      0

[roseway]

Answering the last question first, you can read a description of what the various terms mean here: http://www.kitz.co.uk/adsl/linestats_errors.htm#params_counters. In brief:

CRC errors are actual transmission errors which require the data packet to be retransmitted. Large numbers of CRCs slow down data transmission and can cause the DSL connection to be unstable.

FEC errors are errors which didn't happen because the Forward Error Correction system enabled the errors to be corrected at the receiving end without requiring retransmission. Large numbers of FECs aren't a problem, except as a possible indicator of an underlying interference problem.

For the first question, there's not really enough information to be certain, but it does appear that G.INP is enabled on the downstream. Vectoring is very unlikely. What modem are you using?

[Tacitus]

For the first question, there's not really enough information to be certain, but it does appear that G.INP is enabled on the downstream. Vectoring is very unlikely. What modem are you using?

Thanks for the reply.

How can you deduce that G.INP is enabled - is it the line that says, "Actual INP:  0.0 symbols  47.0 symbols"?

The modem is a Zyxel 3300.  I got it from a friend who decided it wasn't playing all that well with an ECI cabinet.  No idea why.  Way too many technical features for what I need but since it was Broadcom based and cheap

[gt94sss2]

How can you deduce that G.INP is enabled - is it the line that says, "Actual INP:  0.0 symbols  47.0 symbols

Yes, the 47 indicates that g.inp is enabled on the downstream

[burakkucat]

With an appropriate CPE, it is possible to determine the G.Inp "on or off" status of the circuit from the output returned by the "xdslcmd info --show" command.

The following example is from an Huawei HG612, which was connected to a circuit that had G.Inp enabled --

Code: [Select]

# xdslcmd info --show
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 10746 Kbps, Downstream rate = 36672 Kbps
Bearer: 0, Upstream rate = 9999 Kbps, Downstream rate = 38691 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): 5.9 7.2
Attn(dB): 19.6 0.0
Pwr(dBm): 12.1 7.4
VDSL2 framing
Bearer 0
MSGc: -6 58
B: 235 236
M: 1 1
T: 0 23
R: 14 16
S: 0.1941 0.7543
L: 10303 2694
D: 8 1
I: 250 127
N: 250 254
Q: 8 0
V: 1 0
RxQueue: 32 0
TxQueue: 16 0
G.INP Framing: 18 0
G.INP lookback: 16 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 207557
OHFErr: 0 78
RS: 2103116680 2196523
RSCorr: 11676 212
RSUnCorr: 0 0
Bearer 1
OHF: 6379019 0
OHFErr: 0 0
RS: 38273743 0
RSCorr: 2 0
RSUnCorr: 0 0

Retransmit Counters
rtx_tx: 8438410 0
rtx_c: 347 0
rtx_uc: 0 0

G.INP Counters
LEFTRS: 5 0
minEFTR: 38707 0
errFreeBits: 60453048 0

Bearer 0
HEC: 0 0
OCD: 0 0
LCD: 0 0
Total Cells: 3328864915 0
Data Cells: 88436198 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 73
SES: 0 0
UAS: 26 26
AS: 102465

Bearer 0
INP: 48.00 0.00
INPRein: 0.00 0.00
delay: 0 0
PER: 0.00 8.70
OR: 0.01 58.79
AgR: 38752.75 10057.90

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: 71192/71194 1465/1472

Notice the mention of "Bearer 1" in the above? That is the indicator of a circuit with G.Inp configured and active.

[Tacitus]

With an appropriate CPE, it is possible to determine the G.Inp "on or off" status of the circuit from the output returned by the "xdslcmd info --show" command.

[ . . SNIP. . .]

Notice the mention of "Bearer 1" in the above? That is the indicator of a circuit with G.Inp configured and active.

Thanks burakkucat.  For some reason I can't login to the device via Telnet even though I have Telnet enabled for remote acccess from my machine's IP address.  Login via terminal hasn't been a problem in the past so I'll have to sort it out and get back to you.

Thanks again for the help.