SMC Networks 6128L2, Installation Manual

Page: 36 / 84

N
ETWORK
P
LANNING
2-6
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: 550 m (1805 ft) for multimode fiber.
• 1000BASE-LX: 5 km (3.2 miles) for singlemode fiber.
• 1000BASE-ZX: 100 km (62.1 miles) for singlemode fiber.
However, power budget constraints must also be considered when
calculating the maximum cable length for your specific environment.