Will Hargrave wrote in a message to Mike Bilow:
 MB> In fact, as you discovered, 10Base-T uses only four of the eight pins.
 WH> Does 100BaseTX use all 8 pins then?
No.  100Base-TX uses two pairs like 10Base-T, but faster.  There is 
100Base-T4 which does use all four pairs.
 
-- Mike
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