Cabletron Systems 42T User Manual

Contents

Cabletron Systems 42T User Manual Manual pdf 27 page image

REQUIREMENTS/SPECIFICATIONS2-8Fiber Optic BudgetThe fiber optic delay budget, which determines the fiber optic cable’smaximum length, should be calculated and taken into consideration in thenetwork design stage. Fiber optic delay budget is determined by summingthe optical signal loss due to fiber optic cable attenuation, in-line splices,and fiber optic connectors.2.2 CABLE RECOMMENDATIONS/TROUBLESHOOTINGThe following sections describe common cable problems andrecommendations for correcting them.CrosstalkCrosstalk is interference caused by signal coupling between different cablepairs contained within a multi-pair cable bundle. Multi-pair cables shouldnot be used for UTP lobe cabling. UTP lobe cabling should be dedicatedto carrying Token Ring traffic. Avoid mixing Token Ring signals with otherapplications (voice, etc.) within the same cable.NoiseNoise can be caused by crosstalk or externally imposed impulses. Ifnoise-induced errors are suspected, ensure that the electrical wiring in thearea is properly wired and grounded and/or try re-routing cabling awayfrom potential noise sources (motors, switching equipment, fluorescentlighting, high amperage equipment).TemperatureThe attenuation of PVC-insulated cable varies significantly withtemperature. Check the cable manufacturer’s specifications. Plenum-ratedcables are strongly recommended in areas where temperatures exceed40˚C. Under such conditions, plenum-rated cables ensure that cableattenuation remains within specifications.