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Catalyst 2950 Desktop Switch Hardware Installation Guide
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Chapter 3      Installation
Connecting to 10/100 and 10/100/1000 Ports
Note On the Catalyst 2950 LRE switches, the four input uplink ports are bundled as two 
logical ports, each consisting of a copper 10/100/1000 port and a fiber-optic SFP 
module slot, respectively. 
Within each logical port, you can use only the copper or the fiber-optic port at one 
time. If the Catalyst 2950 LRE switch senses more than two connections for both 
logical ports, by default, the switch chooses the fiber-optic connections over the 
copper connections.
See the “SFP Module Slots” section on page 2-14 for more information on LRE 
uplink logical ports.
Connecting devices that do not autonegotiate or devices with manually set speed 
and duplex parameters can reduce performance or result in link failures between 
the devices. To maximize performance, choose one of these methods for 
configuring the ports:
• Let the 10/100 ports autonegotiate both speed and duplex, let the 10/100/1000 
ports on the LRE switches autonegotiate both speed and duplex, and let 
the 10/100/1000 ports on the Catalyst 2950G-24-EI-DC switch only 
autonegotiate speed.
• Set the speed and duplex parameters on both ends of the connection.
When connecting the ports on the Catalyst 2950G-24-EI-DC and 
Catalyst 2950ST-24 LRE 997 switches to other devices, follow these guidelines:
Caution To comply with the intrabuilding lightning surge requirements, intrabuilding 
wiring must be shielded, and the shield for the wiring must be grounded at both 
ends.
Caution The Catalyst 2950G-24-EI-DC or Catalyst 2950ST-24 LRE 997 switch is suitable 
only for intrabuilding or nonexposed wiring connections.