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summat
(member) Thu 24-Jul-14 01:47:11

Weird increase in attainable rate

[link to this post]

This is a little weird.

I had a powercut about 12 days ago, and ever since my attainable rate has seriously jumped up.

Previously:

Retrain Reason: 0
Max: Upstream rate = 32212 Kbps, Downstream rate = 97084 Kbps
Path: 0, Upstream rate = 20000 Kbps, Downstream rate = 79987 Kbps

Text

Mode:                   VDSL2 Annex B
VDSL2 Profile:          Profile 17a 
Discovery Phase (Initial) Band PlanUS: (0,95) (880,1195) (1984,2771)
DS: (32,859) (1216,1959) (2792,4083) 
Medley Phase (Final) Band PlanUS: (0,95) (880,1195) (1984,2771)
DS: (32,859) (1216,1959) (2792,4083) 
VDSL Band Status         U0      U1      U2      U3      D1      D2      D3Line Attenuation(dB):    0.1     6.5     9.7     N/A     4.5     9.5     16.0
Signal Attenuation(dB):  0.1     6.4     9.6     N/A     4.5     9.5     16.0SNR Margin(dB):          7.9     8.9     17.9    N/A     10.7    10.7    10.4
TX Power(dBm):          -10.4   -128.0   -9.0    N/A     8.8     7.4     7.4

* These stats were with older firmware, I have since (over a month ago though) flashed to a more recent one on my HG612, but my attainables didn't really change between firmwares.

Now:

Retrain Reason: 0
Max: Upstream rate = 37357 Kbps, Downstream rate = 147172 Kbps
Bearer: 0, Upstream rate = 20000 Kbps, Downstream rate = 79987 Kbps

Text

Mode:                   VDSL2 Annex B
VDSL2 Profile:          Profile 17a 
Discovery Phase (Initial) Band PlanUS: (6,31) (882,1193) (1984,2770)
DS: (33,857) (1218,1959) (2795,4083) 
Medley Phase (Final) Band PlanUS: (6,31) (882,1193) (1984,2770)
DS: (41,857) (1218,1959) (2795,4083) 
VDSL Band Status         U0      U1      U2       U3      U4     D1      D2      D3Line Attenuation(dB):    0.1     6.7     10.4     N/A     N/A    4.6     10.1    16.8
Signal Attenuation(dB):  0.1     6.7     10.3     N/A     N/A    5.3     9.9     16.7SNR Margin(dB):          8.5     10.0    20.1     N/A     N/A    11.3    11.2    11.3
TX Power(dBm):          -11.0   -57.8   -10.5     N/A     N/A    9.0     7.4     7.4

What the heck? This survived a reboot of the modem earlier today with numbers staying pretty much identical, so it can't be 'nice conditions' when the modem rebooted after the powercut. The 'max' figures are changing too so they're not 'stuck'.

Edited by summat (Thu 24-Jul-14 02:20:56)

R0NSKI
(fountain of knowledge) Thu 24-Jul-14 02:17:51

Re: Weird increase in attainable rate

[re: summat] [link to this post]

Interleaving being applied to the line can cause downstream max to increase, but that doesn't explian the increase in the max upstream.

I have seen my attainable do weird things, I had my max upload increase substantially, whilst my downstream decreased a lot, the sync also followed in this case, stayed like that for a while (weeks) then reverted to what it was before.

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summat
(member) Thu 24-Jul-14 02:22:35

Re: Weird increase in attainable rate

[re: R0NSKI] [link to this post]

I'll keep an eye on it I guess.

Weird that there such a massive jump, though.

I have no interleave (and don't think I ever have had it) and line is usually up for months on end with no resyncs.

kevinrduke
(regular) Thu 24-Jul-14 07:10:35

Re: Weird increase in attainable rate

[re: summat] [link to this post]

I use to get about 62 Mb this has dropped to about 52 Mb with cross talk.

I to had a power cut (whole estate) about 12 days ago and it returned to 62 Mb for about 12 days and has now gone back to about 52 Mb.

I assume that when the power came back on there was no cross talk on the line which is why I synced back at 62 Mb for a while.

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