Cisco Catalyst 2970 - Connecting to 10 BASE-T- and 100 BASE-TX-Compatible Devices; Connecting to 1000 BASE-T Devices

Appendix B Connector and Cable Specifications
Connector Specifications
B-2
Catalyst 2970 Switch Hardware Installation Guide
OL-6422-01
Note You can use the mdix auto interface configuration command in the CLI to enable
the automatic medium-dependent interface crossover (Auto-MDIX) feature.
When the Auto-MDIX feature is enabled, the switch detects the required cable
type for copper Ethernet connections and configures the interfaces accordingly.
Therefore, you can use either a crossover or a straight-through cable for
connections to a copper 10/100/1000 or 1000BASE-T SFP module port on the
switch, regardless of the type of device on the other end of the connection.
The Auto-MDIX feature is enabled by default on switches running Cisco IOS
Release 12.2(18)SE or later. For releases between Cisco IOS
Release 12.1(14)EA1 and 12.2(18)SE, the Auto-MDIX feature is disabled by
default. For configuration information for this feature, refer to the switch software
configuration guide or the switch command reference.
Connecting to 10BASE-T- and 100BASE-TX-Compatible Devices
When connecting the ports to 10BASE-T- and 100BASE-TX-compatible devices,
such as servers, workstations, and routers, you can use a two or four twisted-pair,
straight-through cable wired for 10BASE-T and 100BASE-TX. Figure B-4 shows
the two twisted-pair, straight-through cable schematics. Figure B-6 shows the
four twisted-pair, straight-through cable schematics.
When connecting the ports to 10BASE-T- and 100BASE-TX-compatible devices,
such as switches or repeaters, you can use a two or four twisted-pair, crossover
cable. Figure B-5 shows the two twisted-pair, crossover cable schematics.
Figure B-7 shows the four twisted-pair, crossover cable schematics.
You can use Category 3, 4, or 5 cabling when connecting to
10BASE-T-compatible devices. You must use Category 5 cabling when
connecting to 100BASE-TX-compatible devices.
Connecting to 1000BASE-T Devices
When connecting the ports to 1000BASE-T devices, such as servers,
workstations, and routers, you must use a four twisted-pair, Category 5,
straight-through cable wired for 10BASE-T, 100BASE-TX, and 1000BASE-T.
Figure B-6 shows the straight-through cable schematics.