Glossary
B-3
congestion
A condition where a portion of the network is overloaded with
more data than can be transmitted in the desired time period.
CSMA/CD (carrier-sense multiple access with collision
detection)
A channel access (contention) method that requires each station to
wait for an idle channel before transmitting. In addition, stations
are able to detect overlapping transmissions (collisions) and
retransmit in the event of a data collision.
data link layer
Layer 2 in the OSI model. Defines frame construction, addressing,
error detection, and other services to higher layers.
datagram
Abbreviated and connectionless single-packet message sent from
one station to another.
data rate (or speed)
The maximum number of bits of information that can be
transmitted per second.
downstream
Refers to the relative position of a station in a network to another
station in the same network. A station is downstream from another
station if it receives data after the other station receives data.
dynamic address
An address “learned” by the ELS10-26, as opposed to addresses
that are manually entered into the Bridge Address Table. The
ELS10-26 “learns” addresses by reading them from the data
packets it processes.
EIA (Electronic Industries Association)
Organization that sets standards for electrical interfaces
(connectors).