Black Box Scan-LAN 80, Руководство пользователя

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SCAN-LAN 80 CABLE SCANNER
RJ-45 — An 8-position telephone-type modular
connector used with twisted-pair cable.
Runt Packet — An Ethernet data packet which is
shorter than the valid minimum packet length
(64 bytes). Usually caused by a collision.
Segment — A network cable terminated at both
ends.
Shielded Twisted Pair (STP) — Twisted-pair cable
encased in an outer metallic sheath. The sheath is
grounded to shield the wire pairs from external
noise.
Short — A near-zero resistance connection between
two wires of a circuit.
Signal/Noise Ratio — The ratio of received signal
level to noise level, measured at the receiver input
(expressed in dB). The S/N ratio may be expressed
as NEXT (dB)-Attenuation (dB), provided idle
channel background noise is low. Higher S/N ratios
provide better channel performance.
Split Pair
— A wiring error in twisted-pair cabling
where a balanced circuit uses one wire from one pair
and the other wire from a different pair. The cable
may have correct pin-to-pin continuity between ends,