I have an ADSL line in the UK with 576kbps download and 288kbps upload speeds.
On my lan I have a mixture of FC1, FC2 and WinXP boxes connected throught a netgear DG834 modem/router.
All machines are fine on download speed but the linux boxes are all only getting about 28-30kbps upload speeds (about 10% of what they should). The Windows box is fine on both download and upload speeds.
This is on 3 seperate linux boxes using both FC1 and FC2.
I've only just noticed this problem having just set up the vsftpd FTP server on one of the FC2 boxes and obviously people trying to download from this server are getting horribly slow speeds or are just getting time out errors
IPv6 is off and I've tried various different kernel versions with the same results.