7
Multiple Hubs Cascading and Long-Haul Connection
3-1 Troubleshooting
Network troubleshooting requires patience and logic. Generally
speaking, the cabling and workstation configurations are the likely first
suspects; network hardware is usually last on the list. It is more likely
for an entire hub to fail instead of just a single port.
3-1.1 Cabling Problems
Network troubleshooting requires patience and logic. Improper Cabling
is the primary cause of most non-workstation problems on Ethernet
network, particularly for 100 Base-TX and -FX networks. It must be
emphasized that genuine twisted-pair cable and fiber optic cable be
used to avoid many types of cabling problems.
• Wiring is definitely the problem if the Link LED does not light.
• Multi-mode fiber cable should match the switch’s fiber
transceiver. Flat telephone extension cables or Cat. 3 wires sold
at electronics stores are not the same as Cat. 5 twisted-pair
cable and will not work in 100Mbps network.
Level 2
Fiber
1/MPR
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Long Haul Intra-hub connection
Level 2
4 Port Fiber ST/SC Switch
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Level 1 4 Port Fiber ST/SC Switch
Level 2 Fiber Switch
