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Appendix D
Glossary
10Base-T—IEEE 802.3 UTP Ethernet. Low-cost Level 3 or better UTP wiring affords
100 meters (328 ft.) of point-to-point link segments. UTP uses RJ45 connectors and
sometimes 50-pin AMP connectors to a patch panel and runs at 10 MHz.
ADDRESS RESOLUTION PROTOCOL (ARP)—The procedures and messages in
any communications protocol which resolve local addresses to those of the network. In
TCP/IP, the protocols for translating between IP addresses and physical addresses.
ASYNCHRONOUS TRANSFER MODE (ATM)—A technology for LAN data
transport that packages the data in short fixed length cells for high-speed transport.
ATM FORUM—An international voluntary organization composed of ATM vendors,
manufacturers, service providers, research organizations and users. Purpose is to
“accelerate the use of ATM products and services through the rapid convergence of
interoperability specifications, promotion of industry cooperation and other activities.”
BIT RATE (BR)—The rate of data throughput on the medium in bits per second.
Ethernet specifies 10 million bits per second.
BIT TIME—The duration of one bit symbol (1/BR). Ethernet specifies a bit time of 100
ns.
BROADCAST AND UNKNOWN SERVER (BUS)—BUS defines that set of functions
implemented in an ATM network that provide LAN-to-LAN transmission support while
a LAN connection is being established, It also supports LAN broadcast services.
CARRIER SENSE—In a LAN, an ongoing activity of a data station to detect whether
another station is transmitting.
CARRIER SENSE MULTIPLE ACCESS with COLLISION DETECT
(CSMA/CD)—This is the access method employed by IEEE 802.3 LAN transceivers, by
which multiple stations compete for use of the transmission medium (coax cable) for
data packet transmission. It provides for a level of error detection should that
transmission be corrupted or impeded by contention for the transmission medium.
COLLISION—An unwanted condition that results from concurrent transmissions on
the physical medium.
COLLISION PRESENCE—Provides the ability to detect simultaneous occurrence of
Manchester-encoded data on the DI and DO and to report such an occurrence as a
collision.
