Cabletron Systems STHI manual General Networking Considerations, Crosstalk, Noise, Temperature

General Networking Considerations

Crosstalk 2

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.

Noise 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.

Temperature 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.

Installation Recommendations 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.

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