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[ChrisD]

My downstream has been sat at this for about 4 weeks.

Output from Vigor 130:

DS Actual Rate          : 67000000 bps
DS Attainable Rate      : 72731832 bps

While I know 2-4 Mbit isn't the biggest issue in the world, it still annoys me.

Is there anything I can do? I tried PlusNet support and they said they'd done a DLM reset... not sure I believed they did as I had no downtime.

[Ixel]

The ISP can't, yet, perform a DLM reset without an Openreach engineer. Either they were fobbing you off or they have access to resetting the DLM caution counter now as per the latest Openreach announcement yesterday (though I have doubts).

Some people I believe have had success in removing banding by applying a manual banding of their own for a while (a week or two perhaps). This can be done with modems with a Broadcom chipset typically via xdslcmd, see the sticky about speed capping at the top of this forum category.

[underzone]

You can apply similar with the Vigor via telnet:

vdsl snr -20      #(2dB less, so 4dB margin - more speed/less stability)

vdsl snr 20       #(2dB more, so 8dB margin - less speed/more stability)

[kitz]

Output from Vigor 130:

DS Actual Rate          : 67000000 bps
DS Attainable Rate      : 72731832 bps

Can you get any more stats than that.   With it being sat dead on 67Mbps then the line could be banded.
Theres also if a line has INP/Interleave applied, then the Max attainable rate goes skewy and is not a true representation of max line rate :/

[ChrisD]

You can apply similar with the Vigor via telnet:

vdsl snr -20      #(2dB less, so 4dB margin - more speed/less stability)

vdsl snr 20       #(2dB more, so 8dB margin - less speed/more stability)

Already at -50 for 6 weeks plus now without issue. Line was previously sat at around 48 for the past 18 months so the increase was most welcome.

Can you get any more stats than that.   With it being sat dead on 67Mbps then the line could be banded.
Theres also if a line has INP/Interleave applied, then the Max attainable rate goes skewy and is not a true representation of max line rate :/

Code: [Select]

> v s
  ---------------------- ATU-R Info (hw: annex A, f/w: annex A/B/C) -----------
   Running Mode            :      17A       State                : SHOWTIME
   DS Actual Rate          : 67000000 bps   US Actual Rate       : 18637000 bps
   DS Attainable Rate      : 72532632 bps   US Attainable Rate   : 18835114 bps
   DS Path Mode            :        Fast    US Path Mode         :        Fast
   DS Interleave Depth     :        1       US Interleave Depth  :        1
   NE Current Attenuation  :       16 dB    Cur SNR Margin       :        2  dB
   DS actual PSD           :     6. 7 dB    US actual PSD        :     6. 9  dB
   NE CRC Count            :     2647       FE CRC Count         :    28652
   NE ES Count             :     1840       FE  ES Count         :    25929
   Xdsl Reset Times        :        0       Xdsl Link  Times     :        1
   ITU Version[0]          : b5004946       ITU Version[1]       : 544e0000
   VDSL Firmware Version   : 05-07-06-0D-01-07   [with Vectoring support]
   Power Management Mode   : DSL_G997_PMS_L0
   Test Mode               : DISABLE
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       17 dB    Far SNR Margin       :        6  dB
   CO ITU Version[0]       : b5004946       CO ITU Version[1]    : 544eb206
   DSLAM CHIPSET VENDOR    : < IFTN >


Code: [Select]

> v s more
  ---------------------- ATU-R Info (hw: annex A, f/w: annex A/B/C) -----------
                  Near End        Far End    Note
 Trellis      :      1               1
 Bitswap      :      1               1
 ReTxEnable   :      0               0
 VirtualNoise :      0               0
 20BitSupport :      0               0
 LatencyPath  :      0               0
 LOS          :      0               0
 LOF          :      0               0
 LPR          :      0               0
 LOM          :      0               0
 SosSuccess   :      0               0
 NCD          :      0               0
 LCD          :      0               0
 FECS         :   39448183            268116 (seconds)
 ES           :   1840            25929 (seconds)
 SES          :      0               0 (seconds)
 LOSS         :      0             115 (seconds)
 UAS          :     33            22440 (seconds)
 HECError     :      0               0
 CRC          :   2647            28652
 RsCorrection :      0               0
 INP          :      0               0 (symbols)
 InterleaveDelay :      0               0 (1/100 ms)
 NFEC         :    255             255
 RFEC         :     16              16
 LSYMB        :   4997            17979
 INTLVBLOCK   :    255             255
 AELEM        :      0            ----


[ChrisD]

It still hasn't moved, am I right in saying my line may have been banded?

[kitz]

Unfortunately it looks like it :/

[Ixel]

Just want to add that a negative margin (-50?) probably won't help DLM budge your banding, a positive margin temporarily probably might eventually get DLM to budge it. Some people have had success.

[underzone]

(-50?)

-50 means -5dB target SNR on the Drayteks

[Ixel]

-50 means -5dB target SNR on the Drayteks

Yeah, I mentioned it because I was wondering if he was still using that setting. If he wants to try what some others have tried in the past, applying a temporary 'harsher' banding of their own to try and encourage DLM to make positive changes, then he needs to do 50 and not -50.

[j0hn]

Indeed. Applying what is essentially a 1dB snrm target margin is possibly the reason the line ended up getting banded.
Certainly my lines ES numbers start to get very high with such a low margin (pre retx).

Lowering the margin will likely take the line below the banding level, so swings and roundabouts.

[ChrisD]

If I put the snr at 0 I get around 48Mbit. If I put it to +50 it will be around 35Mbit. I'd rather stick with what I have. Like I said in my OP, it's not exactly the end of the world, just more annoying than anything.