RuggedCom RS400 Manual Do Utilizador

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Ethernet Ports 
 
 
ROS™  v3.5 
98 
RS400 
When the port is half-duplex it is accomplished using 'backpressure' where the switch simulates 
collisions causing the sending device to retry transmissions according to the Ethernet backoff 
algorithm. When the port is full-duplex it is accomplished using PAUSE frames which causes 
the sending device to stop transmitting for a certain period of time. 
LFI 
Synopsis: { Off, On } 
Default: Off 
Enabling Link-Fault-Indication (LFI) inhibits transmitting link integrity signal when the receive link 
has failed. This allows the device at far end to detect link failure under all circumstances. 
NOTE: this feature must not be enabled at both ends of a link. 
Link Alarms 
Synopsis: { Off, On } 
Default: On 
Disabling link state alarms will prevent alarms and LinkUp and LinkDown SNMP traps from 
being sent for that port. 
  
Note  
If one end of the link is fixed to a specific speed and duplex type and the peer auto-negotiates, 
there is a strong possibility that the link will either fail to raise, or raise with the wrong settings on 
the auto-negotiating side. The auto-negotiating peer will fall back to half-duplex operation, even 
when the fixed side is full duplex. Full duplex operation requires that both ends are configured as 
such or else severe frame loss will occur during heavy network traffic. At lower traffic volumes the 
link may display few if any errors As the traffic volume rises the fixed negotiation side will begin to 
experience dropped packets while the auto-negotiating side will experience excessive collisions. 
Ultimately, as traffic load approaches 100% the link will become entirely unusable. These problems 
can be avoided by always configuring ports to the appropriate fixed values.