BT DLM

Would I be right in thinking that a new ADSL connection will be subject to the BT DLM system for up to 14 days? It's a long time since I was on max ADSL I've forgotten.

On connection day a BT Speedtest gave me around 6mbps which was fine. Now, 10 ten days later it seems to have settled at 3.4mbps.

Sync 8128, IP profile 7150, can't get line stats until I return to the business on Tuesday. However the line attenuation was less than 32 dB.

The DLM system runs forever,

The first 10 days are a training period, where the system tries to learn your speed, to update its databases, the speed is in no way fixed. If the line gets better or worse then the actual experience will vary.

If IP profile is 7150 then the BT DLM has down nothing at all to the line, you appear to have a maximum speed ADSL based connection.

you appear to have a maximum speed ADSL based connection.

Surely all connections have a maximum speed. Not sure what you mean there. We're on a "Up to 20Mb download speeds."

Estimated line speed:
7Mb (This may vary between 6Mb and 8Mb) - Checked on 2011-05-19 22:09:14

Doesn't look like you are. If the upload connection speed is 440kbps you almost certainly are not.

If you can find the full router stats, and also see if it tells you ADSL, ADSL2 or ADSL2+ that will confirm what you are on, but it smells of ADSL.

In reply to a post by wingco1:

you appear to have a maximum speed ADSL based connection.

Surely all connections have a maximum speed. Not sure what you mean there. We're on a "Up to 20Mb download speeds."

Estimated line speed:
7Mb (This may vary between 6Mb and 8Mb) - Checked on 2011-05-19 22:09:14

Plusnet advertise the product as 'up to 20Mb', but that is subject to the exchange status (20CN, 21CN etc). 8128 sync / 7150 profile is the highest synce and profile for ADSLmax (not ADSL2, ADSL2+).

See what's going on in the exchange, has it been upgraded to 21CN?

Not use of word appear - not you defintely do.

8128 is the maximum sync for ADSL mode with BT Wholesale.

If your exchange has WBC then you might see more if

a) Line is capable
b) The DLM has not been capped at 8Meg.

The up to 20Meg, is basically what is possible at a large number of exchanges, but you should have received a line based estimate during the sign up process, which is what you should be comparing to.

Doesn't look like you are.

Sorry I appear to have mislead. What I'm saying is, we are on a max adsl connection, and synching at 8128mbps with a 7150 profile.

We did receive 6mbps download on the day of activation, but it appears to have stabilised at 3.4mbps. This would appear to be lower than expected. However I will attend the premises this evening and obtain the router stats.

Stats.

Uptime: 11 days, 4:26:22
DSL Type: G.992.1 annex A
Channel mode: Interleave
Maximum Bandwidth (Up/Down) [kbps/kbps]: 1,168 / 10,720
Bandwidth (Up/Down) [kbps/kbps]: 448 / 8,128
Data Transferred (Sent/Received) [kB/MB]: 0.00 / 425.33
Output Power (Up/Down) [dBm]: 12.0 / 20.0
Line Attenuation (Up/Down) [dB]: 9.0 / 20.5
SN Margin (Up/Down) [dB]: 27.0 / 16.0
Vendor ID (Local/Remote): TMMB / TSTC
Loss of Framing (Local/Remote): 0 / 0
Loss of Signal (Local/Remote): 0 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 0 / 0
FEC Errors (Up/Down): 42 / 9,507
CRC Errors (Up/Down): 15 / 525
HEC Errors (Up/Down): 10 / 755

BT Speed test confirmed the 8128 and 7150 figures and gave a dl speed of 3878mbps.

I understand it could be exchange contention, however I would like some reassurance that the PN profile isn't stuck at a lower figure. Is there a way of checking via the Members Centre?

It's in your Member Centre, called Current Line Speed.

Why are you on an ADSL connection not ADSL2+? That line would connect between 18Mbps and 20Mbps. Exchange not WBC-enabled?

Edited by RobertoS (Mon 06-Jun-11 20:58:59)

Consistently at 3.4Mbps now? Very strange, might be something like a profile mismatch on one of the backend wholesale systems. Happy to take a look tomorrow if you like?

Exchange not WBC-enabled?

Correct.

It's in your Member Centre, called Current Line Speed.

Thanks but I can't see it.

Happy to take a look tomorrow if you like?

That would be appreciated thanks. The business, and therefore the bb connection, is only open from 7 to 9pm on weekdays. It therefore makes it difficult to run any tests at other times. Obtained a dl speed of 3878mbps earlier this evening.

It seems to be associated with "Estimated line speed". I just did a search for a post where I suggested it and the person couldn't find it either. Then someone posted the click-sequence to find it. I couldn't find the post !

Edited by RobertoS (Mon 06-Jun-11 22:08:10)

https://portal.plus.net/my.html?action=data_transfer...

Thanks for that. I posted the details earlier in the thread If Chris can't find anything tomorrow it must be due to Exchange congestion.

The details you quoted earlier didn't include the Current Line Speed.
If it isn't on the link then there is a fair chance that Plusnet haven't received a delta report although when this happens it usually defaults to 2000kbps I think.
This is what you should be seeing

Estimated line speed:
<as you posted>
Current line speed:
<should be a value here> Mb

The telling bits (my bold):

In reply to a post by wingco1:

Bandwidth (Up/Down) [kbps/kbps]: 448 / 8,128
Line Attenuation (Up/Down) [dB]: 9.0 / 20.5
SN Margin (Up/Down) [dB]: 27.0 / 16.0

A few things that I can tell you based on my own connection:

My downsteam attenuation is 30.5dB (8128 / 7150 sync and profile) and I get 6.7 Meg, so you should probably get speeds between 6.7 and 7.1 Meg.

Your CRC errors are low considering the uptime, so I would look to getting that connection onto fastpath rather than interleaved (makes for better pings and a slightly faster connection). My own stats:

Downstream :
FEC : 1
CRC : 5836
HEC : 6271
Upstream :
FEC : 1295
CRC : 65345
HEC : 32785

Up : 13 days 22 hours

If I had those attenuation figures on my setup I would expect almost full profile speeds.

My noise margin (SN Margin) is 8.5dB however, so perhaps the value on your connection of 16.0 could be lower. Wait 3-5 days without reboots to see if it drops, and/or contact Plusnet for a SNR margin target reset.

Looks like it just arrived Current line speed: 7.15 Mb

Drop me a PM with the username or ticket number from the account and I'll take a look.

Done.

Thanks, I've been through a few different tests and can't find any profile inconsistency on any system. I've put the results on a closed ticket on the account for you to view.

The next step I'd suggest is a single reboot of the router and then if the problem persists, raise it at faults.plus.net and we'll get it looked at.

Thanks for that.