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Glossary
bridging
A Layer 2 process to block or forward frames based on MAC
layer addresses. Bridges are lower speed, lower port density switches.
broadband
A transmission methodology for multiplexing several inde-
pendent signals onto one cable. In telecommunications, broadband is classi-
fied as any channel with bandwidth greater than 4kHz (typical voice grade).
In LAN terminology, it is classified as a coaxial cable on which analog sig-
naling is employed. Also known as "wideband." Contrast with: baseband.
broadcast
A data frame or packet that is transmitted to every node on the
local network segment (as defined by the broadcast domain). Broadcasts are
known by their broadcast address, which is a destination network and host
address with all the bits turned on. Also called "local broadcast." Compare
with: directed broadcast.
broadcast domain
A group of devices receiving broadcast frames initi-
ating from any device within the group. Because they do not forward broad-
cast frames, broadcast domains are generally surrounded by routers.
broadcast storm
An undesired event on the network caused by the simul-
taneous transmission of any number of broadcasts across the network seg-
ment. Such an occurrence can overwhelm network bandwidth, resulting in
time-outs.
brute force attack
A brute force attack bombards the resource with
attempted connections until successful. In the most common brute force
attack, different passwords are repeatedly tried until a match is found that
is then used to compromise the network.
buffer
A storage area dedicated to handling data while in transit. Buffers
are used to receive/store sporadic deliveries of data bursts, usually received
from faster devices, compensating for the variations in processing speed.
Incoming information is stored until everything is received prior to sending
data on. Also known as an "information buffer."
bursting
Some technologies, including ATM and Frame Relay, are consid-
ered burstable. This means that user data can exceed the bandwidth nor-
mally reserved for the connection; however, this cannot exceed the port
speed. An example of this would be a 128Kbps Frame Relay CIR on a T1--
depending on the vendor, it may be possible to send more than 128Kbps for
a short time.
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