Cabletron Systems 100BASE-FX, Руководство по кабельной продукции

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Cabling Types 4-3
Ethernet Media
Office
Office AUI cable is a thinner cable that is more convenient to use on many
environments than standard AUI. This lighter-gauge AUI cable is made up of four
pairs of AWG 28 wire, which is thinner (at 0.26 inch) and much more easily flexed,
but can only be run to a maximum distance of 16.5 meters.
Office AUI cable is intended to be used in places where standard AUI cable would
be cumbersome and inflexible. Typically, office AUI is used in locations where a
large number of workstations are concentrated in a single area.
Coaxial Cable
Coaxial cable is a cabling type where two or more separate materials share a
common central axis. While several types of networking cables could be
identified as having coaxial components or constructions, there are only two cable
types that can support network operation using only one strand of cabling with a
shared axis. These are commonly accepted as the coaxial cables, and are divided
into two main categories: thick and thin coaxial cable.
Thick Coaxial Cable
Thick coaxial cable (also known as thick Ethernet cable, “thicknet,” or 10BASE5
cable), is a cable constructed with a single solid core, which carries the network
signals, and a series of layers of shielding and insulator material. The shielding of
thick coaxial cable consists of four stages. The outermost shield is a braided metal
screen. The second stage shield, working inward, is usually a metal foil, but in
some brands of coaxial cable may be made up of a second screen. The third stage
consists of a second braided shield followed by the fourth stage, a second foil
shield. The various shields are separated by non-conductive insulator materials.
Figure 4-2. Thick Coaxial Cable Diagram
Foil Shield
Braided Shield
Insulator
Outer Jacket
Solid Core
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