B-2
Glossary
backbone
The major, central transmission path for a network. A backbone
usually handles high-volume, high-density traffic. Typically a
backbone connects various LANs into an integrated network.
bandwidth
A measure of the amount of traffic a given medium can handle at
one time: The communications capacity (measured in bits per
second), of a transmission line or of a specific path through a
network. Greater bandwidth generally means more information
can be sent through a circuit during any given period of time.
BPDU (bridge protocol data unit)
A data unit transmitted as part of the IEEE 802.1d Spanning Tree
Protocol. The exchange of BPDUs allows bridges within a network
to logically configure the network as a single spanning tree.
bps (bits per second)
The basic unit of data communications rate measurement.
bridge
An intelligent, protocol independent device used to connect
similar or dissimilar LANs.
bursty
Adjective used to describe sporadic heavy volumes of network
traffic (e.g., bursty traffic).
bypass
Optical or electronic isolation of a station from the network. A
bypass situation typically occurs as a result of a station failure or
shutdown; the bypass allows the network to function normally,
except for the absence of the missing station.
concentrator
A device that provides attachment points for stations that are not
connected to the ELS10-26. The concentrator is connected directly
to the network; the stations connect to the concentrator.