Re: [Hampshire] [OT] Curious Network Issue

Sean Gibbins wrote:
> First up, this is OT to the point of being a WinXP Prof related issue,
> so read no further if that causes offence!
>
> Now, I have an odd problem with regard to my wife's Inspiron 1300's
> mini-pci wifi card. Essentially it grinds to a halt on certain sites,
> namely egg, Amazon and Tesco. From what I can gather this usually occurs
> after she has authenticated and especially when she is trying to pay for
> an item.

I had a similar problem with vpn tunnels and a windows firewall.
The firewall is responsible for provision of the entire IP stack
and like MS does a completely p*ss poor job.

My problem was that fragmented packets due to unbalanced network
configurations MSS/MUR et.al cause fragments to be "lost" or placed
in random order in the sygate firewall end.

This could be proved by

1) turning off the firewall - everything worked.

2) when on a tcptrace of the http traffic showed blocks of >1K requests
being "rubik cubed". This will not help with https traffic :-(

So, for me a windows firewall could not traverse a (misconfigured) VPN
tunnel but I could traverse it without the firewall.

You may have the same problem when traversing the two networks (one to
your router/linux box) and then via the MRU on your internet
connection). Fixing the fragmentation config may work but note that
fragmentation *DID* work ok when I disabled the windog firewall
which was the cause of the problem.

Jacqui