CHAPTER 2 | Netw ork
Planning
Application
Notes
APPLICATION NOTES
1. Full-duplex operation on ly applies to point-to-point access (such as when a
switch is attached to a workstation, server or anothe r switch). When the
switch is connected to a hub, both devices must opera te in half-duplex
mode.
2. For network applications that require routing between d issimilar network
types, you can attach these switches direct ly to a multi-protocol router.
However, if you have to interconnect distinct VLANs or IP subnets, you can
take advantage of the wire-speed Layer 3 routing provided by these
switches.
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 (3.1 miles) for single-mode fiber
1000BASE-LH: 70 km (43.5 miles) for single-mode fiber
10GBASE-SR: 300 m (984 ft) for multimode fiber
10GBASE-LR: 10 km (6.2 miles) for single-mode fiber
10GBASE-ER: 40 km (24.8 miles) for single-mode fiber
However, power budget c o n s tr ai n ts must also be considered when
calculating the maximum
cable
length
for your specific environment.
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