[plug] Network Issues (Full/Half Duplex?)

[Timothy White]

** This is mainly for people have network issues (or might be able to 
fix mine)
As I now have some time on my hands I have been investigating a network 
problem that I have had for years. Basically the problems was that 
network communications between My Linux box and the Windows boxes on the 
network was not working. I could connect but when trying anything that 
required more traffic than ssh the connection would slow down with 
packets getting further and further apart (time between each packet.)
Changing the MTU doesn't work and it only happens between Windows and 
Linux (on a specific box) and not between the Linux boxes or the windows 
boxes.
Now that I have a few more Linux boxes (and converted a few windows 
boxes) I have discovered the real problem and why it worked at one stage.
[1]Basically ALL my Linux boxes where running at half duplex with some 
at 10Mb[2] and some at 100Mb. The problem computer was at 100Mb. I could 
easily send a file to the 10Mb computers as the hub forced the sending 
computers to go slower. For the 100Mb computers it would fail as they 
could recieve at high speeds but where of course half duplex which lead 
to lots of packet collisions and the slow down.
Now that I have more Linux boxes I have worked out what does and doesn't 
work.[3]
It appears to me that I ether need to get my Linux box to work at Full 
Duplex. Does anyone else know another way to fix it?
It is a  3Com Corporation 3c905C-TX/TX-M [Tornado] (rev 6c) and from 
what I have read the driver is broken and that is why it won't go into 
Full Duplex. Does anyone have a fix (with out putting all the computers 
on a 10Mb HD hub)?
Thanks
Tim
[1] The problem as I see it with my limited network knowledge
[2] I am talking Mega-bits here
[3]
 Works:
Windows -> 100Mbs FD Switch -> Linux 10Mbs HD
Windows -> 100Mbs FD Switch -> Linux 100Mbs FD
Linux 10Mbs HD -> 100Mbs FD Switch -> Linux 100Mbs HD
Windows -> 100Mbs FD Switch -> 10Mbs HD Hub -> Linux
Linux -> 10Mbs HD Hub -> 100Mbs FD Switch -> Linux 100 Mbs HD

Doesn't Work:
Windows -> 100Mbs FD Switch -> Linux 100Mbs HD
Linux 100Mbs FD -> 100Mbs FD Switch -> Linux 100Mbs HD

So basically.
100Mbs FD -> 100Mbs HD doesn't work without a 10Mbs HD hub in the line

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Tim White
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