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[skwark]

Hi,

I've been struggling to achieve the min target 30mbps downstream rate on my line not long after it was installed. The max is 38Mbps and the min is 30Mbps and the OR engineer confirmed a line test of 35+ when installed. Sure enough in the first few days I was seeing >33Mbps down. But after a raft of disconnects I saw it quickly plummet.

My downstream SNR now seems to remain at 16+ and IP profile is currently 23Mbps, despite BTHH5 and a TP Link VR9000 reporting max data rates of 40+

BT support said the "guaranteed" minimum should be 27Mbps but that my line is operating within "normal parameters" (and had a tried turning the hub off and on again?). Just truly awful response but there you go.

Any ideas why the SNR is so high? Upstream is spot on at 6.7db and 8Mbps

Thanks

[Dray]

Sounds like DLM has capped your downstream sync to raise the noise margin due to many disconnections being detected on your line.

[skwark]

So just a case of sitting tight for a week or two to see if it regains some confidence in the line?

I think the TP Link was a bit flaky and may be to blame, hence plugging the BTHH back in and seeing how it fares.

[burakkucat]

If your DS SNRM is of the order of 16 dB then something is not correct with your circuit.

Which device are you currently using as CPE? The BT-HH5 or the TP-LINK VR900?

I am very wary of the BT-HH5, as it has had problems from the first day of its release. Its biggest problem was spontaneous rebooting, often many times in a day and so much so that the DLM assumes the line is faulty . . . . 

There is one technique that I have suggested to others, previously, and that is at the end of the day to power down the modem & disconnect the lead linking the device to the filter (centralised or micro, as the case may be). Leave the device in that state overnight and only power it up & reconnect it when you next need Internet access. Sometimes by leaving the DSLAM's line-card port in a quiescent state, allowing it to "relax" overnight, can clear an abnormal state of the circuit.

Please note that the above technique should only be performed once . . . Do not use it each and every night! 

[skwark]

I have had the BT-HH5 connected for the past two days (with no dropouts or reboots) after seeing no improvement and gradually increasing downstream SNR and lowered profile with the VR900. Unfortunately it doesn't report connection time so wasn't sure just how often (if at all recently) it was losing sync. It was pretty dreadful in the first week for reliability/speed but seemed to settle down. I hated the Home Hub, but I think I may have had my cards marked by relying on the VR900 in those first few weeks when the line went live.

I'll try your suggestion 

[skwark]

Well I'm not sure how long I need to wait to see if things improve, but 20hrs back online and DS SNRM has actually slipped up to 18db.

I managed to keep the line clear for about 15hrs but I'm guessing whatever the issue is this didn't resolve it.

[Weaver]

In that case, at 18dB you definitely have a fault or interference problem and will need a man with a spanner, I'm afraid.

[Dray]

I managed to keep the line clear for about 15hrs but I'm guessing whatever the issue is this didn't resolve it.

Do you mean you had the HH5 unplugged for 15 hours?

It may give you more insight if you can monitor the router stats using for example Routerstats-Hub which works with a HH5 type A (but not the type B).

[skwark]

Do you mean you had the HH5 unplugged for 15 hours?

It may give you more insight if you can monitor the router stats using for example Routerstats-Hub which works with a HH5 type A (but not the type B).

Correct. Type B here.

[skwark]

You were right about the Home Hub. On further inspection is was dropping its connection every morning around 9am. I've since replaced it with a Billion so I can at least get an insight to the connection details (and had success with a Billion for years on my previous ADSL2 link).

That maintained a connection for around 4 days before a disconnection this morning. Prior to that SNRM has gradually increased to 19db but does fluctuate (the lowest being 15db). It's currently at 19.4db as I type this.

The only other change I've noticed is the interleaving depth reduced from 4 to 2 on the downstream after the disconnection this morning (could that be the cause if DLM altered it?) and the upstream sync rate has actually increased by 1Mbps.

[burakkucat]

That does read as if the DLM is cautiously making small improvements to your service. 

If you "sit tight" and resist the urge to make "adjustments" you should find that the DLM will slowly make further incremental improvements.

[skwark]

That's what I'm hoping too...