3Com 9400 Network Hardware User Manual


 
20 C
HAPTER
3: C
ABLING
C
ORE
B
UILDER
9400 P
ORTS
Cabling Gigabit Ethernet Ports
Before you cable the system, consider this Caution.
CAUTION:
You
may not
want to connect the
network cables before you power on the system
(chapter 4) if you need to configure trunks, resilient
links, or the Spanning Tree Protocol (STP). To avoid
bridge loops, configure trunks, resilient links, and
STP using the Administration Console
before
you
connect the cables and after you power up the
system. See the
Command Reference Guide
and
the
Implementation Guide
for your system.
Guidelines for Gigabit Ethernet Cabling
For all Gigabit Ethernet cabling, keep the ports and
connectors free of dust. See “Cleaning Dirty Fiber
Optic Ports and Connectors” on page 40 for details.
Recommended Distances for
1000BASE-SX Ports or Transceivers
When you cable 1000BASE-SX ports or transceivers,
verify that the length of the fiber cable from the
system to any attached device does not exceed these
recommended distances:
Use 62.5-micron MMF fiber with a modal
bandwidth specification of 160 MHz*km for
distances of up to 220 m (722 ft).
Use 62.5-micron MMF fiber with a modal
bandwidth specification of 200 MHz*km for
distances of up to 275 m (902 ft).
Use 50-micron MMF fiber with a modal bandwidth
specification of 400 MHz*km for distances of up
to 500 m (1645 ft).
Use 50-micron MMF fiber with modal bandwidth
specification of 500 Mhz*km for distances of up to
550 m (1805 ft).
Recommended Distances for
1000BASE-LX Transceivers
When you cable 1000BASE-LX transceivers, verify
that the length of the fiber cable from the system to
any attached device does not exceed these
recommended distances:
Use 62.5-micron MMF fiber with a modal
bandwidth specification of 160 MHz*km for
distances of up to 550 m (1805 ft).
Use 62.5-micron MMF fiber with a modal
bandwidth specification of 200 MHz*km for
distances of up to 550 m (1805 ft).
Use 50-micron MMF fiber with a modal bandwidth
specification of 400 MHz*km for distances of up
to 550 m (1805 ft).
Use 50-micron MMF fiber with a modal bandwidth
specification of 500 MHz*km for distances of up
to 550 m (1805 ft).
Use 9-micron SMF fiber for distances of up to
10 km (6.2 mi). The specification requires and
specifies 5 km (3.1 mi).
Use a conditioned launch cable to connect the
1000BASE-LX transceiver to multimode fiber. Using
this cable ensures reliability over the maximum 550 m
distance.