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Crosstalk is interference caused by signal coupling between different cable 
pairs contained within a multi-pair cable bundle. Multi-pair cables should 
not be used for UTP lobe cabling. Avoid mixing Token Ring signals with 
other applications (voice, etc.) within the same cable.

3

Noise can be caused by either crosstalk or externally induced impulses. 
Outside systems (motors, switching equipment, fluorescent lighting, high 
amperage equipment) may produce electrical interference causing noise. 
The number and quality of cable connections also contribute considerably 
to noise levels. To reduce noise induced errors, it may be necessary to 
re-route cabling away from potential noise sources, or to ensure that the 
electrical wiring in the area is properly wired and grounded, or to replace 
connectors along affected segments.

4

Signal attenuation varies significantly with temperature when 
PVC-insulated cable is used. In areas where temperatures exceed 40˚C, it 
is strongly recommended that plenum-rated cables be used instead to 
ensure that signal attenuation remains within specifications. 

5

In addition to complying with the cable specifications presented in 
Appendix A, TPIM Specifications, the cabling installation should comply 
with the following recommendations to obtain optimum performance 
from the network:

•

UTP cabling should be free of splices, stubs, or bridged taps.

•

Metal troughs, ducts, etc. carrying Token Ring signals should be 
properly grounded.

•

Cables should be routed away from sources of electrical noise, such as 
power lines, fluorescent lights, electric motors, radio interference, and 
heavy machinery.

•

Token Ring signals should not be routed through UTP cables that exit 
a building or which are adjacent to cables either exiting a building or 
exposed to lightning strikes and power surges.