Installation guide

A-82 Cisco 4000 Series Installation Guide
Ethernet Cable Pinouts
Figure A-18 Straight-Through Cable Pinout (Connecting 100E RJ-45 Interface to a
Hub or Repeater)
Figure A-19 Crossover Cable Pinout (RJ-45 Connections Between Hubs and
Repeaters)
The module transceiver must be equipped with the appropriate connector, depending on the
media type used for the MII connection. Connectors can be ST-type for optical fiber, RJ-45
for 100BaseT4, and so on. Figure A-20 shows the pin orientation of the female MII
connector on the 100E module.
The MII receptacle uses 2-56 screw-type locks, called jackscrews (shown in Figure A-20),
to secure the cable or transceiver to the MII port and provide strain relief. MII cables and
transceivers have knurled thumbscrews (tightened with the fingers) that fasten to the
jackscrews on the module’s MII connector (shown in Figure A-20). In contrast, the RJ-45
modular plug has strain relief functionality incorporated into the design of its standard
plastic connector.
Hub or repeater100E
3 TxD+
6 TxD–
1 RxD+
2 RxD–
3 RxD+
6 RxD–
1 TxD+
2 TxD– H7050
Hub or repeater
3 TxD+
6 TxD–
1 RxD+
2 RxD–
3 TxD+
6 TxD–
1 RxD+
2 RxD– H3138
Hub or repeater