Speed

[Saturday]

Originally Posted by ichilton

I was on about the output from the Netgear router I posted which didn't mention CRC, FEC etc.

Then you need to look again. Pretty much all there other than FEC which, as I've explained a couple of times recently, are corrected errors and so, unimportant.

Originally Posted by ichilton

I find the O2User speed test to always report lower than all the other speed tests to me i'm afraid

Possibly because (some) other speedtest servers misreport the speed. Or maybe the O2 servers were overloaded at the time you used it. Speedtest servers by and large are very poor other than giving an approximation. It's ridiculous how often you see people post speedtest results that are >90% of their sync speed which isn't technically possible.

Originally Posted by ichilton

What DNS servers do you recommend btw?

I don't recommend any but am using OpenDNS at the moment as it happens.

[ichilton]

Hi Saturday,

I was getting a lot of CRC errors with fastpath so i got them to turn interleaving back on (but left the 3db profile), so I have 33ms ping times to bbc.co.uk but i'm getting good speed test speeds:

o2user: 5728kbps, 796kbps
Speedtest: 6.09Mbps, 1.04Mbps
Namesco: 6087kbps, 1043kbps

I dont seem to get any connection drop outs - the sessions are staying up until I reboot the router (like last night when we tripped the power out doh!).

Uptime:	0 days, 16:12:56
DSL Type:	G.992.5 annex A
Bandwidth (Up/Down) [kbps/kbps]:	1,243 / 7,056
Data Transferred (Sent/Received) [kB/kB]:	0.00 / 0.00
Output Power (Up/Down) [dBm]:	12.0 / 19.0
Line Attenuation (Up/Down) [dB]:	31.0 / 53.0
SN Margin (Up/Down) [dB]:	2.5 / 1.0
Vendor ID (Local/Remote):	TMMB / BDCM
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):	12 / 0
FEC Errors (Up/Down):	3,027 / 6,108,783
CRC Errors (Up/Down):	3,027 / 1,730
HEC Errors (Up/Down):	2,063 / 1,404

That's after it's just been (and still is) raining.

Do you think I should get it set back to a 6db profile or would you say those CRC errors look 'normal' for the connection uptime?

Is that "Loss of Signal" anything to worry about?

Thanks,

Ian

[Saturday]

The CRC errors are a bit high but the LOS is nothing to worry about.

A 3db profile and interleaving on doesn't really make sense. I don't understand why you're obsessing over a connection that was genuinely excellent before you started fiddling with it.

Personally, I'd go to a standard 6db profile and fastpath. Then if I had to, I'd increase the noise margin myself by a db or two. It generally is just better to leave things alone unless you have very unusual line characteristics - otherwise you're just chasing shadows. ADSL is a very clever technology and will generally set up the optimum connection unaided if left alone.

[ichilton]

Hi,

6db and fastpath? - so interleaving off? - did you mean to say that or did you mean the default of 6db+interleaving?

With interleaving off I got lower ping's but I seemed to get lots of CRC errors - unless that was the 3db profile and 6db+fastpath would be ok?

Thanks,

Ian

[Saturday]

Errors don't matter unless you can see the impact of them when using your connection. Personally I'd rather have low pings and sacrifice a bit of sync speed by raising the noise margin - either because I was having issues or more likely because it bothered me to know I had high error levels. YMMV

This thread is getting very long and I feel it's beginning to go round in circles

[ichilton]

Hi,

I think I might just take your original suggestion and set it back to default - i.e get the SNR set back to 6db and leave interleaving on for now - get used to the stable connection and what I can get out of it and then maybe think about going to fastpath at a later date...

Thanks for your help!

Ian

[ichilton]

Hi,

How odd!

What were you saying about not messing with things? - I dont quite understand why but i'm getting more errors now i've set it back to a standard 6db profile with interleaving on than I was before on 3db!:

Uptime:	0 days, 9:51:43
DSL Type:	G.992.5 annex A
Bandwidth (Up/Down) [kbps/kbps]:	1,157 / 6,225
Data Transferred (Sent/Received) [kB/kB]:	0.00 / 0.00
Output Power (Up/Down) [dBm]:	12.0 / 18.5
Line Attenuation (Up/Down) [dB]:	31.0 / 53.0
SN Margin (Up/Down) [dB]:	5.5 / 3.5
Vendor ID (Local/Remote):	TMMB / BDCM
Loss of Framing (Local/Remote):	11 / 0
Loss of Signal (Local/Remote):	2 / 0
Loss of Power (Local/Remote):	0 / 0
Loss of Link (Remote):	0
Error Seconds (Local/Remote):	35 / 0
FEC Errors (Up/Down):	493 / 1,450,234
CRC Errors (Up/Down):	493 / 7,420
HEC Errors (Up/Down):	214 / 5,769

Now i'm confused lol!

Ian

[Saturday]

A "dog with a bone" comes to mind

Your downstream noise margin is showing as 3.5db so either your noise margin has not been set back to 6db (check by rebooting the router) or your noise margin has dropped. If the latter then that's entirely normal as the noise margin will swing by a couple of db between daytime and evening. If the last reboot was in the morning then in the evening the noise margin will show as lower. If in the evening then in the morning it will show as higher.Surely you've read the tutorials I pointed you to?

Your router is reporting an uptime of over 9 hours. If you want to see the errors since any changes reboot the router (even power cycle it) to clear the data (FEC will probably stay high as I've previously mentioned). If those stats are covering the full 9 hours then yes, they're a little high but snapshots can't tell you what is really going on. You need trends and consistency in measurement. If you're continually making changes then the data is fairly meaningless.

Lastly, is any of this actually affecting your connection? If not then stop looking at your stats all the time and just enjoy your excellent, cheap and reliable O2 broadband connection

[ichilton]

Hi,

That was on the night after a reboot about lunchtime when the profile was set back to 6db and no changes were made since then.

I just thought it was odd that I was getting more errors with the slower, normal connection than the faster tweaked one - might as well have it faster!

Connection was terrible this morning - did a speed test and got 0.2Mbps downstream which explained it - hoping that is a one off glitch at O2's side...tried again a bit later and was getting a speed test over 3Mbps which was obviously better but still slow for a 6000kbps sync...

Ian

[Saturday]

Assuming you used a reliable server to measure and that's with a wired connection then there's something seriously wrong.