Cabletron Systems 100BASE-FX, Руководство по кабельной продукции

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Cabling Terms
2-2 Physical Components
Jumper Cabling
Jumper cabling is a term that identifies short, inexpensive cables that are used to
make connections between nearby cabling devices. Typically, workstations and
network devices are connected to the facility cabling of a site with jumper cables.
Run
A “run” of cabling is a single end-to-end cable path in a networked facility. The
cable run typically begins at a network device such as a hub or bridge and ends at
a workstation or other end node. The cable run, if calculated, must include all
areas on the cable to which signals will travel. On point-to-point media, such as
UTP or fiber optics, this will be the same as the measure of cabling between
stations. In a shared media environment, however, the measure of a run must
include the total length of the shared cable being used, regardless of the distance
between stations on that cable.
A cable run includes the facility cabling, jumper cabling, and any passive cable
management devices, such as wallplates, patch panels, and punchdown blocks,
between the two devices. When a specific type of cabling is referred to when
identifying a cable run, the term refers only to the total length of that type of cable
in the installation.
As an example, if a thick coaxial cable run is referred to in an installation
description, it is concerned with the total length of coaxial cable and does not
include the AUI cables used to connect stations to transceivers on the thick coaxial
cable. If a UTP cable run is referred to, it includes only the jumper cables, patch
panels, wallplates, and facility cabling between the devices in question.
Wire
The wire terms listed below deal with the components that make up a physical
cable.
Core
The core of a wire is that portion of the wire upon which the electrical (or light, in
the case of fiber optics) signals of network communications travel. In all cases, the
term core refers to the transmissive center of the cable or wire in question. The
term core is most often used when referring to a cable that has a single
transmission path. Cables with multiple transmission paths cannot have an
overall core.