Specifications

Glossary
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BRI Short for basic rate interface, it’s a form of
ISDN used in home and small business applica-
tions. A 2B+1D BRI service has two B channels and
a single D channel for signaling and control uses.
bridge In local area networks, an interconnec-
tion between two similar networks. Also the hard-
ware equipment used to establish such an
interconnection.
broadband transmission A term used to
describe analog transmission. Requires modems for
connecting terminals and computers to the net-
work. Using frequency division multiplexing, many
signals or sets of data can be transmitted simultane-
ously. The alternative transmission scheme is base-
band, or digital, transmission.
brownout An AC supply voltage drop in which
the power does not shut off entirely but continues
to be supplied at lower-than-normal levels.
BSOD See blue screen of death.
BTX Short for Balanced Technology Extended, this
is a PC and server architecture introduced by Intel
in September 2003. BTX is designed to improve
internal cooling by placing memory and processors
in line with cooling fans.
bubble memory A special type of nonvolatile
read/write memory introduced by Intel in which
magnetic regions are suspended in crystal film and
data is maintained when the power is off. A typical
bubble memory chip contains about 512KB, or
more than four million bubbles. Bubble memory
failed to catch on because of slow access times mea-
sured in several milliseconds. It has, however,
found a niche use as solid-state “disk” emulators in
environments in which conventional drives are
unacceptable, such as in military or factory use.
buffer A block of memory used as a holding
tank to store data temporarily. Often positioned
between a slower peripheral device and the faster
computer. All data moving between the peripheral
and the computer passes through the buffer. A
buffer enables the data to be read from or written
to the peripheral in larger chunks, which improves
performance. A buffer that is x bytes in size usually
holds the last x bytes of data that moved between
the peripheral and CPU. This method contrasts
with that of a cache, which adds intelligence to the
buffer so that the most often accessed data, rather
than the last accessed data, remains in the buffer
(cache). A cache can improve performance greatly
over a plain buffer.
bug An error or a defect in a program; it can be
corrected through program patches (for applica-
tions or operating systems) or firmware updates (for
BIOS chips).
burn-in The operation of a circuit or equipment
to establish that its components are stable and to
screen out defective parts or assemblies.
BURN-Proof Short for buffer underrun error-proof,
it’s a technology developed by Sanyo to prevent
buffer underruns during the creation of CD-Rs.
BURN-Proof, which has been licensed to many
CD-RW drive makers, enables a drive to pause the
burning process and continue after sufficient data
is available in the drive’s buffer. The drive and
CD-mastering software must both support BURN-
Proof for this feature to work. Ricoh’s JustLink
works in a similar fashion. See also lossless linking.
burst mode A memory-cycling technology that
takes advantage of the fact that most memory
accesses are consecutive in nature. After the row
and column addresses for a given access are set up,
burst mode can then access the next three adjacent
addresses with no additional latency.
Burst Static RAMs (BSRAMs) Short for
Pipeline Burst SRAM, BSRAMs are a common type of
static RAM chip used for memory caches where
access to subsequent memory locations after the
first byte is accessed takes fewer machine cycles.
bus A linear electrical signal pathway over which
power, data, and other signals travel. It is capable
of connecting to three or more attachments. A bus
is generally considered to be distinct from radial or
point-to-point signal connections. The term comes
from the Latin omnibus, meaning “for all.” When
used to describe a topology, bus always implies a
linear structure.
bus mouse An obsolete type of mouse used in
the 1980s that plugs into a special mouse expan-
sion board (occasionally incorporated into a video
card) instead of a serial port or motherboard mouse
port. The bus mouse connector looks similar to a
motherboard mouse (sometimes called PS/2 mouse)
connector, but the pin configurations are different
and not compatible.
Appendix A
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