Hi,

This is obviously in the DSL Stats page, but which one of the following does it mean?

1. The Near End (my modem) detected a loss of signal. I.e. either the BT end or the line caused a signal drop?

2. The Near End (my modem) caused a loss of signal failure by dropping the line.

Sorry if this is a dumb question, but it will help me understand an issue with constant dis-connections. I.e. whether it's my 2860 dropping the line, or the line is being dropped elsewhere.

Thanks,
Richard

Can't quite answer the question because I'm confused about that myself but I can give some other info which may help (based on VDSL2 observations): -

• If the 2860 modem 'decides' to retrain (too many errors etc.) then LOS & LPR do not increment.


• If the DLM causes the cabinet card to retrain then the LOS & FE LPR will increment (in some multiple of 2)


• I am net sure what happens if there is a physical line break, bu easy enouh to test.


• If you have a good (80/20) line with then some lines will keep resetting if using VT2/VT3/BT firmware. VT1 & the new VT5 (NBN) firmware do not cause this.


• If you have a lower or variable quality line then VT2/VT3/BT firmware may reset daily (overnight) due to DLM, or even more often during the day. What seems to happen is that actual rate is too close to attainable and causes CRCs so DLM resets it. VT1 resets less but still every 2 days on average. VT5 (NBN) is much more stable and I have seen even a very variable quality line up for 10 days (once it settles down).


• DLM retrains always happen overnight / early hours of the morning.


• Even if the 2860 decides to do a retrain, DLM may follow up with it's own one later due to collecting stats over a 24h period but you can tell the difference via the FE LPR counter.

VT5 (NBN) firmware is available as beta in uk, or from the US ftp site and has the same main firmware but all new modem code which seems to use the dynamic error correcting features much more.

Thanks for the detailed answer - yes the LOS increases by 2 each time there's an issue.

The connection I'm referring to is actually an ADSL2+ Annex M version. (Although FTTC is available, it gives an appalling upload speed of 500k, not the 1750k I'm getting on Annex M.)

Anyway, I did try VT1 (yes, I know vectoring is a VDSL thing, but thought I might try it anyway) and it gave some weird results - halving the bits per bin for most frequencies. So that got discarded.

VT2 sync'd the same as the BT version, but the modem became very unstable - pages became unresponsive, until the dreaded 'firmware is corrupted' warning came up, which then forced me away from playing with the modem code to try and recover things.

So I'll leave the VT1/2/3/5 code alone, sticking the the BT version. But I do have another 2860 that I've put on the line just in case there's a hardware issue, so I'll see if my problem goes away.