P
ORT
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SSIGNMENTS
24
Straight-Through Cable
If the twisted-pair cable is to join two ports and only one of the ports has
an internal crossover (MDI-X), the cable used must be straight-through.
Crossover Cable
If the twisted-pair cable is to join two ports and either both ports are
labeled with an “X” (MDI-X) or neither port is labeled with an “X”
(MDI), a crossover must be implemented in the wiring.
Straight-Through RJ-45 Pin Assignments
End 1
End 2
1 (RD+)
1 (TD+)
2 (RD-)
2 (TD-)
3 (TD+)
3 (RD+)
6 (TD-)
6 (RD-)
Crossover RJ-45 Pin Assignments
End 1
End 2
1 (TD+)
3 (RD+)
2 (TD-)
6 (RD-)
3 (RD+)
1 (TD+)
6 (RD-)
2 (TD-)