Improper Network Topologies
It is important to make sure that you have a valid network topology. Common topology faults include excessive cable length and too many repeaters or hubs between end nodes. In addition, you should make sure that your network topology contains no data path loops. Between any two ends nodes, there should be only one active cabling path at any time. Data path loops will cause broadcast storms that will severely impact your network performance.
Diagnosing LED Indicators
The switch can be easily monitored through panel indicators to assist in identifying problems.
If the power indicator does turn on when the power cord is plugged in, you may have a problem with the power outlet or power cord. However, if the switch powers off after running for a while check for loose power connections, power losses or surges at power outlet. If you still cannot resolve the problem, contact your local dealer for assistance.
Cabling
cable for 
Category 3, 4 or 5 cable for 10Mbps
connections or 100
Category 5 cable for 100Mbps connections. Be sure that
the length of any
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