New ADSL Install - Sim Provide - Line Changes

Hi All,

Yesterday had a simultaneous provide from MPF LLU which could've been a ton better; landline down for 10 hours, broadband could've been active all day when I was trying to work but Plusnet don't activate username on RADIUS until BT Wholesale give the ok.

Since this provide the line characteristics seem to have changed.

Obviously we're under DLM still however there is a clear issue. When the land line phone is in use the SNR margin drops from 12dB to 4dB upstream, and from 6dB to 5dB downstream.

This is a long line however this did not happen before the move.

There is a couple of dB drop in attenuation which seems to be due to the BT Wholesale MSAN using ADSL 2 rather than ADSL2+, downstream sync has dropped from 2,020kb/s to 1,767kbps and upstream from 605kbps to 443kbps.

Land line usage bleeding into the ADSL concerns me. It's not an issue on my side, the same Openreach filtered NTE is in place, which leads me to think a problem was caused at the exchange when the line was rejumpered.

Of course just to complicate things it's also possible that the fault was induced by work in the street cabinet as new lines are being provisioned but I struggle to image a fault that would cause this and am far more inclined to blame a dodgy SMPF splitter port in the exchange.

This seem a reasonable thought process?

Here are line stats. The low up time is from a loss of sync when the land line was used.

My next step is to dig out a router with the best ADSL/2/2+ chipset I have ever seen, the Argon AR432, and hope it likes the Infineon chipset in the BT Wholesale MSAN.

Along of course with getting the line itself fixed.

Uptime: 0 days, 1:23:28
DSL Type: ITU-T G.992.3
Bandwidth (Up/Down) [kbps/kbps]: 443 / 1.767
Data Transferred (Sent/Received) [MB/MB]: 34,45 / 33,98
Output Power (Up/Down) [dBm]: 12,8 / 0,0
Line Attenuation (Up/Down) [dB]: 39,3 / 68,5
SN Margin (Up/Down) [dB]: 12,0 / 6,1
System Vendor ID (Local/Remote): TMMB / ----
Chipset Vendor ID (Local/Remote): BDCM / IFTN
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): -
Error Seconds (Local/Remote): 181 / 0
FEC Errors (Up/Down): 0 / 0
CRC Errors (Up/Down): 15 / 318
HEC Errors (Up/Down): 6 / 393

FEC Errors (Up/Down): 0 / 0 - is it on Fastpath ?

Does sound a bit like a flaky joint on the jumpering, unless a downpour has infiltrated overnight.

In reply to a post by yarwell:

FEC Errors (Up/Down): 0 / 0 - is it on Fastpath ?

Does sound a bit like a flaky joint on the jumpering, unless a downpour has infiltrated overnight.

Yes Phil, I presume DLM hasn't seen fit to switch to an interleaved / INP profile.

This was happening yesterday as well before the rain came to visit, I was just busy with other things.

opting into interleave on such a long line is common advice.

I am sure that DLM will be interleaving the line in time...


Uptime: 0 days, 2:47:34

Line Attenuation (Up/Down) [dB]: 39,3 / 68,5
SN Margin (Up/Down) [dB]: 12,1 / 6,0

Error Seconds (Local/Remote): 301 / 0

CRC Errors (Up/Down): 32 / 506
HEC Errors (Up/Down): 12 / 620

A picture is worth a thousand words.

Uptick in Bitswaps too.

As a sideline Plusnet's order support was horrendous. The last person spoken to was a robot who kept talking over the account holder and interrupting her to recite the same information over and over again.

She stubbornly refused to pass her to a manager which was just bizarre. Are the Plusnet CS team on some kind of incentive / disincentive programme to avoid escalating issues?

Said manager once she finally relented and got him on the line was able to do exactly what we asked for in 5 minutes flat.

Really incredibly unimpressed with the whole deal so far.

Edited by deleted (Tue 23-Jul-13 14:30:09)

I would opt-in to interleaving in the hope of keeping the SNR margin at 6.

DLM is already there:

Channel Mode: Interleaved

Zero FEC still. Correcting nothing.