losing network connection when uploading
 

i've got a wierd problem with my dsl/ethernet connection. my network setup is this:
3 computers (dhcp) downstairs go to a 100Mbit switch which is uplinked to a wireless bridge.
that is talkign to a wireless (802.11b) router connected our dsl and a windows machine(dhcp).

i've been noticing problems when uploading with gftp. i'll get about 0.5 or 1 meg done and my network connection dies. the computer right next to me going into the same switch works fine but everything times out on my machine (pings, web page requests, etc.). I tried restarting the network service and that didnt help. i rebooted last time and my connection was fine after that. this time however a reboot didnt fix it. i had to unplug and replug my network cable in the switch and everything was fine.

does anyone know why this would happen?