Cisco CATALYST 5500 9 PORT GIGABIT ETHERNET SWITCH MODULE 规格指南
Switching Module Installation 3-15
Connecting Gigabit Ethernet Modules
Figure 3-9
Gigabit Ethernet Module Network Interface Connector (SC Type)
GBIC Cabling Restrictions
You must observe the following optical-fiber cabling restrictions when using GBICs:
•
The minimum cabling distance for 1000BaseSX and 1000BaseLX/LH GBICs is
6.5 feet (2 meters).
6.5 feet (2 meters).
•
When using the 1000BaseLX/LH GBIC with 62.5-micron diameter MMF, you must
install a mode-conditioning patch cord between the MMF fiber-optic network and the
GBIC. The mode-conditioning patch cord (CAB-GELX-625 or equivalent) is required
to comply with IEEE standards. The IEEE found that link distances could not be met
with certain types of fiber-optic cable cores. The solution is to launch light from the laser
at a precise offset from the center by using the mode-conditioning patch cord. At the
output of the patch cord, the LX/LH GBIC is compliant with the IEEE 802.3z standard
for 1000BaseLX.
install a mode-conditioning patch cord between the MMF fiber-optic network and the
GBIC. The mode-conditioning patch cord (CAB-GELX-625 or equivalent) is required
to comply with IEEE standards. The IEEE found that link distances could not be met
with certain types of fiber-optic cable cores. The solution is to launch light from the laser
at a precise offset from the center by using the mode-conditioning patch cord. At the
output of the patch cord, the LX/LH GBIC is compliant with the IEEE 802.3z standard
for 1000BaseLX.
•
You must insert a 10-dB inline optical attenuator between the fiber-optic network and
the receiving port on the 1000BaseZX GBIC at each end of the link if the link length is
less than 15.5 miles (25 km).
the receiving port on the 1000BaseZX GBIC at each end of the link if the link length is
less than 15.5 miles (25 km).
•
You must insert a 5-dB inline optical attenuator between the fiber-optic network and the
receiving port on the 1000BaseZX GBIC at each end of the link if the link is greater than
15.5 miles (25 km), but less than 31 miles (50 km).
receiving port on the 1000BaseZX GBIC at each end of the link if the link is greater than
15.5 miles (25 km), but less than 31 miles (50 km).
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