Fast Sync/Speedtest - slow actualy D/L speeds

Hi, long time reader - first time poster )

I'm with O2 - ADSL+ .6mile from exchange

Last year I was getting around 5-8MB download speeds - after a few problems it has now (past 2 months) settled to 1-1.5MB download with loads of dropouts/disconnects (PS3 games disconnecting when no one else is and router dropping IP address)

I feel I'm traffic shaped as when I hit 1.2MB speeds downloading the browser stops on all PC's/Mac/Ps3/iPhone feeling like I've maxed out the connection (as I used to on 0.5MB connection on other houses.

I've been raising it with O2 who just say I should be getting 17MB as thats what the router syncs at and they have not traffic managed me.

The router stats after a reboot are,
DSL Type: G.992.5 annex A
Bandwidth (Up/Down) [kbps/kbps]: 1,403 / 16,903
Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.0 / 18.5
Line Attenuation (Up/Down) [dB]: 16.0 / 29.5
SN Margin (Up/Down) [dB]: 4.5 / 3.5
Vendor ID (Local/Remote): TMMB / BDCM
Loss of Framing (Local/Remote): 33 / 0
Loss of Signal (Local/Remote): 4 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 4 / 0
FEC Errors (Up/Down): 6 / 11,369
CRC Errors (Up/Down): 6 / 15
HEC Errors (Up/Down): 2 / 9

Now to me they are excellent.

When I use TB Speedtest it confirms a nice fat 12MB+ Download and 1MB up, when I use TB test files it maxes out at 1.2MB Download - regardless of how many I have going at a time and testing other servers at the same time it still only totals about 1.2 - 1.5MB - freezing surfing at the same time.

I'm stumped here - and apparently after 2 hours and 3 people at O2 - so are they. I'm trying to get them to get BT to change my pairs at the local box but they claim to have no ability to do so.

I've tried different routers, have the master socket stripped to just the 2 wires, no extensions and changed all leads/splitter.

Its been this way for about 2 months, Ive been running TBBMeter which confirms my max 1.x MB throughput.

Anyone had similar experience?

Any ideas what to try next or how to get O2 to get BT to do something.

Any idea why I only get 10% actual speed of all the different speedtests I've tried?

Many thanks, Antony.

I'd get them to increase your target SNR margin from 3dB to 6dB. You seem to have a lot of errors in (I guess) a shortish time. That might cause some of the problems you are seeing.

Your line itself appears to be fine.

Hi john, thanks for the fast reply, o2 have made a lot of changes over the last 2 days one of which was to lower the Snr from 6 to 3 to see if that helped, he did that today actually and it did add 2MB tithe sync and .3mb tithe download, I did notice a lot, as in 150k errors over the few days I was watching it before I started trying to get it fixed.

Lowering the SNR margin will increase the sync at the expense of stability. I think you would benefit from a lower sync but more stable line, i.e. a 6 or 9dB target SNR margin. If you are getting lots of errors that may account for your poor throughput.

Are you confusing 'bits/sec' and 'bytes/sec'? 12Mbits/sec is about 1.2MBytes/sec. I really think there is no problem with your broadband, O2 LLU does not do any traffic shaping.

I wonder if this could be RWIN or a malware problem.

I would suggest booting the PC in Safe mode with Networking and trying a download. If that improves things then it could be something that is on the PC or a recent update to the AV software.

To check RWIN etc have a look at broadband computer tweaks

In reply to a post by dsergeant:

Are you confusing 'bits/sec' and 'bytes/sec'? 12Mbits/sec is about 1.2MBytes/sec. I really think there is no problem with your broadband, O2 LLU does not do any traffic shaping.

Oh Dear....

I think your right, actually having played with Conversion of Data Transfer Rate Units I know your right, I'm being a total numpty and confusing kB/s with Mbps and kbps, with my different download managers all using different measuring methods!

i do still have a problem with the line dropouts and will get them to put the SNR back to 6, or 7 and see if that helps then if it stablises I'll get it changed to FAST rather than interleaved to fix the ping which may help the PS3 games from dropping and lag on it.

Thanks for your help, I'll make sure I check the conversion page next time!

In reply to a post by Hatari:

I wonder if this could be RWIN or a malware problem.

I would suggest booting the PC in Safe mode with Networking and trying a download. If that improves things then it could be something that is on the PC or a recent update to the AV software.

To check RWIN etc have a look at broadband computer tweaks

Updated out of date link it is now RWIN for XP users