2
Network Planning
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 connected 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 the length of fiber optic cable for a single switched link should
not exceed:
• 1000BASE-SX/LX: 550 m (1805 ft) for multimode fiber or 5 km (3.2 miles) for
single-mode fiber.
• 100BASE-FX: 2 km (1.24 miles) for multimode fiber or 20 km (12.43 miles) for
single-mode fiber.
However, power budget constraints must also be considered when calculating
the maximum cable length for your specific environment.
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