CHAPTER B |
Cables
Fiber
Standards
ADJUSTING EXISTING CATEGORY 5 CABLING TO RUN 1000BASE-T
If your existing Category 5 installation does not meet one of the test parameters
for 1000BASE-T, there are basically three measures that can be applied to tr y
and correct the problem:
1. Replace any Category 5 patch cables with high-performance
Category
5e
or
Category
6
cables.
2. Reduce the number of conne ctors used in the link.
3. Reconnect some of the connectors in the link.
FIBER STANDARDS
The International Telecommunication Union (ITU-T) has standard ized various
fiber types for data networks. Th es e a re s umm ar ized in the following table.
Table 19: Fiber Standards
ITU-T
Standard Description Application
G.651 Multimode Fiber
50/125-micron core
Short-reach connections in the 1300-
nm or 850-nm band
G.652
Non-Dispersi on-Shifted
Fiber
Single-mode, 9/125-m icr on c ore
Longer spans and ext e nd e d r e ac h .
Optimized for operation in the 1310-
nm band. but can also be used in the
1550-nm band
G.652.C Low Water Peak Non-
Dispersion-Shifted Fiber
Single-mode, 9/125-m icr on c ore
Longer spans and ext e nd e d r e ac h .
Optimized for wavelength-division
multiplexing (WDM) transmission
across wavelengths from 1285 to
1625 nm. The zero dispersion
wavelength is in the 1310-nm region.
G.653 Dispersion-Shifted Fiber
Single-mode, 9/125-m icr on c ore
Longer spans and ext e nd e d r e ac h .
Optimized for operation in the region
from 1500 to 1600-nm.
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