Thank you prlzx, and everyone for your replies, I believe you are correct re the self-tuning aspect, but it is still fun learning about it...(fun? maybe I should get a life?)...

In reply to a post by prlzx:

If you could get hold of a long ethernet cable it would be better to test OpenSuse's speed on a wired connection

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I might lug my box downstairs and try it wired and wireless from there and compare, or maybe boot the family PC to a liveCD and try that.

In reply to a post by prlzx:

For example before 'n'Wi-Fi came along, some manufactures had different (proprietary) enhancements for 'g' (Super G etc) which might only be present in the XP driver.

In reply to a post by wakou222:

and the other one (Netgear WPN111) REFUSES to work with linux, despite carrying the the same chipset

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I think you have hit the nail squarely on the head, and this is why this particular adapter refuses to work at all with openSuse, or indeed any flavour of Linux according to Google (one guy reported he had got it working with Ubuntu, maybe he was lying )

In reply to a post by prlzx:

Other factors might be the version of Flash or Java in OpenSuse. If you have the Adobe Flash plugin try TBB's Flash-based tester too.

I had problems with this (java) but I think I have them cracked. I have tried both, results with both vary wildly, but both seem to average out at about 10Mb. I sometimes get above this (15-20) but rarely and not consistently, ie occasional spikes.

In reply to a post by prlzx:

If you are happy with the internet connection generally it might be better to test your wi-fi by transferring files back and forth between two machines over the local network. TBB's test files are also suitable to this.

I have a couple of other small problems, I shall post them in the BT forum area.....

In reply to a post by prlzx:

MTU is normally discovered and monitored automatically, both in Windows and Linux

In Vista & Win7 yes, but not in XP, where it just take default value (of 1500 I think). Hence popularity of tweaking programs, like TCP Optimizer, and variable pinging.

wakou222,

Both a friend and myself have been trying out Ubuntu 10.10 for the past few weeks and we both found that connecting to the net can often be a problem. He was trying to connect to a Homehub wirelessly from a Vista laptop both with the onboard card and a usb adaptor and couldn't hold the connection for more than a minute or two. I had a few problems from start-up, wired to a router, and had to uncheck and recheck, sometimes several times, the network settings box to get a connection - however once connected it would hold and speeds would be the same as under Windows XP.

His wireless connection problem was solved by installing Ubuntu as the single OS on a desktop computer and my problem was solved by using a TG585 v7 router upgraded with generic 8.2.6.5 firmware. Incidentally the dslreports.com "Tweaking for speed" test shows the Ubuntu auto internet setup is now fully optimised.

This info may not help you, but at least you know others have managed to resolve similar issues

4M2.

In reply to a post by XRaySpeX:

In reply to a post by prlzx:

MTU is normally discovered and monitored automatically, both in Windows and Linux

In Vista & Win7 yes, but not in XP, where it just take default value (of 1500 I think). Hence popularity of tweaking programs, like TCP Optimizer, and variable pinging.

Link

XP might not auto-adjust RWIN but MTU is set via PMTU Discovery, (on by default) unless you turn it off by tweaking.

XP has an additional setting EnablePMTUBHDetect (off by default) to spot when a network is behind a router that blocks ICMP but also needs a lower MTU to reach it. (Edit) you can turn that on if you have problems with a few websites when the rest are ok.

One reason for the popularity of tweaking programs is that people have previously tweaked their settings for dial-up connections, so subsequently on progressing to DSL the settings were not optimal.

A second reason is that some people just like to tweak things (me too)

A third is that some internet servers and firewalls were misconfigured such that they send full size packets with DF flag set, but then block all ICMP (including ping) so not get the replies back telling them they needed to fragment or send smaller packets. People then try to workaround that by setting their own MTU lower (even if there was nothing much wrong with the client settings).

In general the best place to set the correct MTU is on the router or device acting as DHCP server then you are only changing settings in one place rather than manually setting each device. Similarly people who like to set static IP for everything might not realise DHCP is giving out more info than just IP addresses and can inform the client about other settings.

If BT Infinity uses PPPoE then yes 1492 may well work better, but modern OSes with their default settings are able to use 1500 on the (link-local) LAN and a detect a lower value for internet-bound traffic.

Edited by prlzx (Fri 04-Mar-11 17:47:38)