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[MrsDaddyCoull]

Hi
my partner has been reasonably happy with his BT broadband connection for the past year, he usually gets a steady 3.5mb connection with little variation. He has noticed however over the last few weeks its gone really low, sometimes under 1mb. We checked last night and it was back up to 3.5mb with a sync speed of 4512. However after slow connection this morning he reset the home hub router and now although his sync speed is still 4480 it appears that his ip profile has been set to 2000.
When we try to do a BT performance test it comes back with an error but reports the ip profile.

Is there likely to be a fault on the line to cause his ip profile to be reset so low?

any thoughts would be appreciated
Lis

here are his router stats



   Help


   
DSL Connection   

Link Information
         
Uptime:   0 days, 4:04:22
Modulation:   G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]:   448 / 4,480
Data Transferred (Sent/Received) [MB/MB]:   26.95 / 36.43
Output Power (Up/Down) [dBm]:   11.5 / 19.5
Line Attenuation (Up/Down) [dB]:   28.0 / 49.0
SN Margin (Up/Down) [dB]:   22.0 / 7.0
Vendor ID (Local/Remote):   TMMB / ALCB
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):   0 / 145,265
CRC Errors (Up/Down):   0 / 91
HEC Errors (Up/Down):   0 / 76
Line Profile:   Interleaved

[kitz]

>> Is there likely to be a fault on the line to cause his ip profile to be reset so low?

Your router stats now show sync speeds within the correct range for your attenuation.  The previous low sync could have been a result of many things not just a line fault.

Im on a "near perfect" line with just 7dB, but on occasions even Ive had a couple of low syncs over the past few years.   Once was a blown fuse, the other was during a period of time when I had workmen in the house using power tools.
The "fault" may also not have been triggered in your own property, but may also be in a neighbouring house.  Theres a list of common culprits that can cause this on the REIN faults page.

Hopefully though perhaps yours was just more of a one off that could be caused by something like a storm or power surge.  If this is the case then your IP profile should soon rise back in line with your sync speed.

[MrsDaddyCoull]

Thanks Kit

I was just surprised the ip profile went from 3500 to 2000 over night. I guess he's stuck with that now for a few days until his sync speed stays constant at around 4500.

Adam has been complaining that his speeds have been bad for the last few weeks, thinking now about your reply, there have been workmen on the railway line for a few weeks, i wonder if that could have made a difference.

Is there any other test to check what your actual ip profile is currently set to, as the bt peformance tester just won't complete a test?

I will get him to keep an eye on his sync speed and ip profile over next week or so

Lis

[roseway]

Unfortunately your IP profile gets dropped very quickly if you have a low-speed resync, but it can take up to 5 days to recover after the connection speed increases again.

I don't know whether BT Internet make the information available to customers, but some ISPs do provide this information on their customer portal.

[MrsDaddyCoull]

Good morning folks
well ive just got to Adams to check his router stats and found that overnight his sync speed had dropped dramatically to 2208, this is obviously happening regularly and causing his ip profile to drop to 2000, the tricky bit is finding out why after a year of having a stable connection.

Is it unusual for the sync rate to drop by half? it seems quite a dramatic drop, whenever mine drops it is usually only a few hundred and may cause my ip profile to drop to the next 500 down (ie 5000 to 4500)

Adam reset his router here are the stats before and after reset

24.2.08 11.10am

DSL Connection   

Link Information
         
Uptime:   0 days, 12:43:29
Modulation:   G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]:   448 / 2,208
Data Transferred (Sent/Received) [MB/MB]:   31.62 / 61.07
Output Power (Up/Down) [dBm]:   11.5 / 17.0
Line Attenuation (Up/Down) [dB]:   28.0 / 48.0
SN Margin (Up/Down) [dB]:   22.0 / 12.5
Vendor ID (Local/Remote):   TMMB / ALCB
Loss of Framing (Local/Remote):   0 / 0
Loss of Signal (Local/Remote):   1 / 0
Loss of Power (Local/Remote):   0 / 0
Loss of Link (Remote):   0
Error Seconds (Local/Remote):   162 / 0
FEC Errors (Up/Down):   0 / 6,400
CRC Errors (Up/Down):   0 / 3
HEC Errors (Up/Down):   0 / 1
Line Profile:   Interleaved
A BT brand


24.2.08 11.11am reset router
   
DSL Connection   

Link Information
         
Uptime:   0 days, 0:00:07
Modulation:   G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]:   448 / 4,544
Data Transferred (Sent/Received) [KB/KB]:   0.00 / 0.00
Output Power (Up/Down) [dBm]:   11.5 / 19.5
Line Attenuation (Up/Down) [dB]:   28.0 / 48.0
SN Margin (Up/Down) [dB]:   22.0 / 6.5
Vendor ID (Local/Remote):   TMMB / ALCB
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):   0 / 0
CRC Errors (Up/Down):   0 / 0
HEC Errors (Up/Down):   0 / 0
Line Profile:   Interleaved

[roseway]

It does rather look like impulse noise (REIN) and the link Kitz gave you above has some tips for diagnosing this sort of problem. Unfortunately there are so many possible causes of this type of interference that tracking it down can be quite difficult.

I'm not sure what router you have, but routerstats is a very helpful utility if you have a suitable router.

[kitz]

Erics explained the gist of it... 
but just to add so that you know whats going on and what to look for on that line

Bandwidth (Up/Down) [kbps/kbps]:   448 / 2,208
SN Margin (Up/Down) [dB]:   22.0 / 12.5
Loss of Signal (Local/Remote):   1 / 0

Bandwidth (Up/Down) [kbps/kbps]:   448 / 4,544
SN Margin (Up/Down) [dB]:   22.0 / 6.5

In your case those are the important figures....
See how on the 1st one you have a lot of "spare" SNR Margin?

That indicates to us that your line has dropped due to Noise, but has now recovered.

The default Target SNR set on your line is 6dB...  therefore any time you have more than say 9dB SNR margin a resync will increase the speed at which you can connect at.
The more SNRM... the higher the increase in sync.  This set of figures show 12.5dB which is about double the spare Margin that your particular line needs.


However on the 2nd set of figures you now have 6dB and the higher sync...
but if a noise event occurs and that figure starts dropping down towards 0dB then the line will drop.
and come back up at the highest it can, whilst having a 6dB SNRM. Once the noise event stops, then your SNRM will go back up...  but you wont get the speed increase until you do a resync.