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Application Notes
1. Full-duplex operation only applies to point-to-point access (such as
when a switch is attached to a workstation, server or another switch).
When the switch is connected to a hub, both devices must operate in
half-duplex mode.
2. Avoid using flow control on a port con nected to a hub unless it is
actually required to solve a problem. Otherwise back pressure jamming
signals may degrade overall performance for the segment attached to
the hub.
3. As a general rule th e length of fiber optic cable for a single switched
link should not exceed:
• 1000BASE-SX: 550 m (1805 ft) using multimode fiber
• 1000BASE-LX: 5 km (3.2 miles) using single-mode fiber
• 1000BASE-LH: 70 km (43.5 miles) using single-mode fiber
• 100BASE-FX: 20 km (12.43 miles) using single-mode fiber
• 100BASE-FX: 2 km (1.24 miles) using multimode fiber
However, power budget constraints must also be considered when
calculating the maximum cable length for your specific environment.