Network Planning
2-6
2
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. For network applications that require routing between dissimilar network types,
you can attach switch units directly to a router.
4. As a general rule the 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.
• 100BASE-LH: 70 km (43.5 miles) using single-mode fiber.
• 100BASE-FX: 15 km (9.3 miles) for single-fiber single-mode links.
However, power budget constraints must also be considered when calculating
the maximum cable length for your specific environment.