eepro100 in 10Mbit mode

Hi,

I am trying to create a network where in the edges are 100Mbit and the 
core is a throttled 10Mbit as follows:
                      |              |
   100Mbit            |     core     |              100Mbit
  |*******| <-------->|   |*******|  |  <-------> |*******|
   switch             |    switch    |             switch
                      |   /   |   \  |
                      |  /    |    \ |
                      | R1    R2   R3|
                      |              |
  |-- edge ------|--------- core -------------|--- edge ------|

R1, R2 and R3 are 3 routers containing eepro100 cards connected to a
Netgear FS105 100Mbit core switch. I would like to throttle these
interfaces to 10Mbits so that the effective throughput of the network
becomes 10Mbit and _queuing_ occurs.

But on using mii-tool to force these interfaces to 10baseT-FD, there are
_many_ collisions on the core switch which kills even a 5Mbit flow to
3Mbit. I have tried 10baseT-HD too, but the collisions still seem to
occur. Is there something fundamentally flawed in this design?

TIA.

ciao,
Amit

-- 
I'm an angel!!! Honest!
The horns are just there to hold the halo up straight.
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                  Amit Kucheria
          EECS Grad. Research Assistant
         University of Kansas @ Lawrence
   (R): +1-785-830-8521 ||| (C): +1-785-760-2871
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