18
16- AND 24-PORT STACK HUBS
Figure 6-2. Wiring diagram for straight-through cables.
6.2 Crossover Cables
When cascading or connecting the Hub to another switch, bridge, or hub through
the UTP port, a modified crossover cable is necessary. With a crossover cable, two
pairs of wires are switched at one connector end. Carry out the following steps to
create a customized, crossover twisted-pair cable:
1. Leave one end of the cable as is, with the RJ-45 connector intact. The wiring
at just one end of the cable needs to be modified.
2. At the other end of the cable, connect wires 1 and 2 to contacts 3 and 6
respectively. Likewise, connect wires 3 and 6 to contacts 1 and 2. Refer to
Figure 6-3.
Figure 6-3. Wiring diagram for crossover cables.
Hub (MDI-X)
1 RD+
2 RD-
3 TD+
6 TD-
Hub (MDI-X)
RD+ 1
RD-
2
TD+
3
TD-
6
Workstation (MDI)
Hub (MDI-X)
RD+ 1
RD-
2
TD+
3
TD-
6
1 TD+
2 TD-
3 RD+
6 RD-
