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[nivek1612]

So I have notice that my FTTC connection is sitting with a SNR of 7.0 - 7.3 on the downstream

Reboots do not seem to change the situation and I'm not banded (or at least don't appear to be) as the resync will move the speed slightly each time (up or down) and its currently at 52325 which does not appear to be a banded profile as I believe they normally are xx999 or xx998 and do not change on reboots. Also my expected range is 44-60 Mbps so at circa 52Mbps I'm in the range.

Any ideas why I'm not sync higher and getting an SNR of around 6 as I would expect

My DSLSTATs can be found under kwillers if anyone is interested   

[nivek1612]

DLM finally woke up

Now SNR 6.1 and sync 56MB

[kitz]

I notice you are on a Huawei cab which has differing Target SNRM profiles

I note that prior to 13th of April you had bouts of extremely high Err Secs sufficient to tigger DLM and for a while your SNRM was 9dB.
You had another high bout of Err/Secs starting around Apr 27th, at which point it looked like your Target SNRm was set at around 7dB. 
As from yesterday you appear to be back at the default 6.3 dB.


You're not the first person Ive seen recently with what appears to be an obvious Target SNRm of ~ 7 dB on a Huawei cabinet after a period of Err Sec instability.  I'm beginning to suspect the Huawei DLM may be making use of various Target SNRm profiles in addition to the 3,4,5,6 that we are already aware of. 

[nivek1612]

I now have dropped to 5 db SNR and seen another 3MB speed increase

[nivek1612]

Now down to 4 dB target and seeing 62MB connection speed

Happy days

Question is how low will it GO ;-)

[WWWombat]

I'm beginning to suspect the Huawei DLM may be making use of various Target SNRm profiles in addition to the 3,4,5,6 that we are already aware of. 

It looks suspiciously like that at the moment - at least sitting nicely in the phased reductions in SNRM going on right now.

Question is how low will it GO ;-)

The first drop, from 7dB to 6dB, went alongside a decrease in FEC (which was slightly unusual, but roughly halved) but an increase in retransmissions (roughly doubled).

The subsequent drops, to 5dB then to 4dB, seem to have resulted in no change to the FEC graphs, or to the retransmission graphs, or to the CRC graphs, or to the ES graphs. That is a little, err, unexpected.