3com 3CDSG8 사용자 가이드

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Ports 

Information page indicate that the link is down when there is a cable connecting a device to 
the switch).  

Note: Auto causes the switch to negotiate the link speed and duplex settings with the 
connected device; this is called Auto-negotiation. All of the other settings cause Auto-
negotiation to be turned off. 

Note:  In full-duplex mode, both ends of a connection can send traffic at the same time which 
effectively doubles the available throughput. In half-duplex mode, only one end of the 
connection can send traffic at any one time. 

When Flow Control is selected on a port (by clicking on the tick-box in the Flow Control 
column), the switch will attempt to slow incoming traffic down when traffic levels are high. It 
does this by sending special Pause packets on full-duplex connections or creating back-pressure 
(deliberately causing collisions) on half-duplex connections. This can increase traffic throughput 
by reducing the number of dropped packets and, as a result, the number of resends that are 
required. However it is not appropriate in all circumstances.  

 

 
 
This page allows you to set up a threshold for incoming broadcast and multicast packets. Too 
many incoming packets can severely cripple the switch and network performance. Rate limiting 
protects the switch and network by keeping the amount of data passing through the ports to a 
safe limit. The use of VLANs and Trunks to partition ports and network devices into separate