[Gllug] iptables and flaky ssh, ftp, vnc

Liam Smit liam.smit at gmail.com
Tue Jun 21 16:58:38 UTC 2005

Hi Tom

802.11 (a/b/g) tends to drop quite a few packets and simply resends
them. SSH and certain other connection based protocols may be upset by
this. I know that the latency for wireless as compared to wired
networks is higher due to the packet dropping and that this can mess
things up. Also statistically the dropped packets will sometimes be
your keep alive packets...

Wireless if fine as long as it is all connected via cables.<g>
Seriously though connect your access points via cat5  and all your
problems should go away. It'll only be one cable to run.


> > >The problem is that when using ssh, ftp or vnc, the connection is often
> > >lost.
> > >
> > By any chance do you live in the flight path of one of the airports?
> > Somewhere around 1/3 of the traffic coming into Heathrow seems to knock
> > my wireless for a loop, and TCP connections therefore drop.
> I'm not near a flightpath, fortunately by the sound of things!
> The connection here is tenuous, but I don't have any problems using ssh
> from my compaq.
> [Thinkpad] <-> [Compaq, iptables] <-> [Belkin router next door]
> That's why I think there must be something wrong with my iptables rules.
> Have you tried using different aerials?
> Tom Weissmann
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