Black Box SCAN-LAN VI, Manual

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GLOSSARY
CDDI — Copper Distributed Data Interface, a variation of the FDDI
standard (ANSI X3T9.5) adapted for 100-Mbps data transmission on
twisted-pair cable. Also called TP-PMD.
Channel — As defined by EIA/TIA TSB-67, the entire horizontal wiring
link connecting end devices in the work area to the hub/concentrator in
the wiring closet. Includes user’s equipment cords at both ends and
horizontal cross-connections (see
Appendix A, Test Standards , Figure A-1).
Characteristic Impedance — An inherent characteristic of the cable. A
measure of resistance to AC current flow (high frequency) by a long cable.
Cheapernet — A nickname for 10BASE2 or ThinNet, a coax-based
Ethernet network.
Coaxial (Coax) Cable — A cable that contains a single center copper
conductor surrounded by insulation material and one or more layers
of metal foil or braided-wire mesh plus an outer protective jacket.
Collision — The result of two stations simultaneously attempting to
transmit data on a shared network transmission medium.
Concentrator — A piece of LAN equipment that allows multiple network
devices to be connected to the network cabling system through a central
point. Also called a hub.
Connecting Block — An interconnecting point for several LAN segments.
Crossed Pair — A twisted-pair wiring error in which a wire pair on one
connector of the cable is wired to a different pair on the other end of the
cable.
Crosstalk — The coupling of a signal between pairs of a multiple-pair cable.
CSA — Canadian Standards Association.
CSMA/CD (Carrier Sense Multiple Access/Collision Detection) —
Ethernet media access method in which stations transmit on a bus
whenever the medium is available and re-transmit when collisions occur.
Decibel (dB) — A logarithmic unit of measure used to express the
amplitude ratio between two signals. dB = 20 log (Vsignal2/Vsignal1).
DC (Direct Current) — A zero-frequency or constant-level signal.