Will Hargrave wrote in a message to Mike Bilow:
 WH>> Does 100BaseTX use all 8 pins then?
 MB> No.  100Base-TX uses two pairs like 10Base-T, but faster.  There is
 MB> 100Base-T4 which does use all four pairs.
 WH> Ahh yes, that's because it works over Cat 4 cable doesn't it? 
100Base-T4 is intended to work over Cat 3.
 
-- Mike
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