Installation guide

1000BASE-T Pin Assignments
B-3
Straight-Through Wiring
If the twisted-pair cable is to join two ports and only one of the ports has an internal
crossover (MDI-X), the two pairs of wires must be straight-through. (When
auto-negotiation is enabled for any RJ-45 port on this switch, you can use either
straight-through or crossover cable to connect to any device type.)
Crossover Wiring
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. (When auto-negotiation is enabled for any RJ-45 port on
this switch, you can use either straight-through or crossover cable to connect to any
device type.)
1000BASE-T Pin Assignments
The table below shows the 1000BASE-T MDI and MDI-X port pinouts. These ports
require that all four pairs of wires be connected. Note that for 1000BASE-T
operation, all four pairs of wires are used for both transmit and receive.
Use 100-ohm Category 5, 5e, or 6 unshielded twisted-pair (UTP) or shielded
twisted-pair (STP) cable for 1000BASE-T connections. Also be sure that the length
of any twisted-pair connection does not exceed 100 meters (328 feet).
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-)
Pin MDI Signal Name MDI-X Signal Name
1 Transmit Data plus (TD1+) Transmit Data plus (TD2 +)
2 Receive Data minus (RD1-) Receive Data minus (RD2-)
3 Transmit Data plus (TD2+) Transmit Data plus (TD1+)
4 Transmit Data plus (TD3+) Transmit Data plus (TD4+)