10/100/1000 Ports - Cisco WS-C2950T-48-SI Hardware Installation Manual

Front-Panel Description
When connecting the switch to workstations, servers, and routers, be sure that the cable is a twisted-pair
Note
straight-through cable. When connecting the switch to hubs or other switches, use a twisted-pair
crossover cable. Pinouts for the cables are described in
For information on how to identify a crossover cable, go to the
on page
The 10/100 ports can be explicitly set to operate in any combination of half duplex, full duplex, 10 Mbps,
or 100 Mbps. They can also be set for speed and duplex autonegotiation, compliant with IEEE 802.3U.
In all cases, the cable length from a switch to an attached device cannot exceed 328 feet (100 meters).
When set for autonegotiation, a port senses the speed and duplex settings of the attached device and
advertises its own capabilities. If the attached device supports autonegotiation, the port negotiates the
best connection (that is, the fastest line speed that both devices support and full-duplex transmission, if
the attached device supports it) and configures itself accordingly.

10/100/1000 Ports

The 10/100/1000 ports on Catalyst 2950T-24, Catalyst 2950T-48-SI, and Catalyst 2950 LRE switches
use RJ-45 connectors and twisted-pair cabling. The ports can connect to these devices:
•
•
•
When connecting the switch to a 1000BASE-T device, be sure to use a four twisted-pair, Category 5
Note
cable.
When connecting the switch to workstations, servers, and routers, be sure to use a twisted-pair
Note
straight-through cable. When connecting the switch to hubs or other switches, use a twisted-pair
crossover cable. Pinouts for the cables are described in
For information on how to identify a crossover cable, go to the
on page
The 10/100/1000 ports on the Catalyst 2950T-24 switch can be explicitly set to operate at 10, 100, or
1000 Mbps, but only in full-duplex mode. The 10/100/1000 ports on the Catalyst 2950T-48-SI and
Catalyst 2950 LRE switches can be explicitly set to operate at 10 or 100 Mbps in full- or half-duplex
mode or at 1000 Mbps in full-duplex mode.
The 10/100/1000 ports can also be set for speed autonegotiation, compliant with IEEE 802.3AB. In all
cases, the cable length from a switch to an attached device cannot exceed 328 feet (100 meters).
Catalyst 2950 Switch Hardware Installation Guide
1-8
B-5.
10BASE-T devices, such as workstations and hubs, through standard RJ-45 connectors and two or
four twisted-pair, Category 5 cabling.
100BASE-TX devices, such as high-speed workstations, servers, hubs, routers, and other switches,
through standard RJ-45 connectors and two or four twisted-pair, Category 5 cabling.
1000BASE-T devices, such as high-speed workstations, servers, hubs, routers, and other switches,
through standard RJ-45 connectors and four twisted-pair, Category 5 cabling.
B-5.
Appendix B, "Connectors and Cables."
"Identifying a Crossover Cable" section
Appendix B, "Connectors and Cables."
"Identifying a Crossover Cable" section
Chapter 1 Overview
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