Network Planning

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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 an other 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 signa ls 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 li nk should
not exceed:
• 1000BASE-SX: 550 m (1805 ft) for multimode fiber.
• 1000BASE-LX: 5 km (3.1 miles) for singlemode fiber.
• 1000BASE-LH: 70 km (43.5 miles) for singlemode fiber.
However, power budget constraints must also be considered when calculating
the maximum cable length for your specific environment.
4. The maximum number of units that can be stacked together are:
• 4 MIL-SM4804G units