NSFNET served as the backbone for the Internet until 1995 by
providing the underlying high-volume links of the Internet to
which other elements attached. See alsoBackbone network.
Backbone network A middle-distance network that inter-
connects local area networks in a single organization with each
other and with the organization’s wide area network and the
Internet. The technology employed is at the high end of that used
for LANs, such as Fast Ethernet or Gigabit Ethernet running over
fiber-optic or twisted-pair cabling. See also Fast Ethernet,
Gigabit Ethernet.
Balanced scorecard A management model (by Kaplan and
Norton) that translates an organization’s goals and strategy into
a “scorecard” of “balanced” measures that include not only finan-
cial metrics but also customer satisfaction, internal processes, and
innovation and learning. Some firms have adopted the same
approach for assessing the performance of an IS organization.
Bandwidth The difference between the highest and the lowest
frequencies (cycles per second) that can be transmitted on a
single medium. Bandwidth is important because it is a measure of
the capacity of the transmission medium.
Bar code label A label consisting of a series of bars used to
identify an item; when the bar code is scanned, the data are
entered into a computer. There are a variety of bar code lan-
guages, the most widely known of which is the Universal Product
Code, or UPC, used by the grocery industry. The use of bar codes
is very popular for high-volume supermarket checkout, depart-
ment store sales, inventory tracking, time and attendance records,
and health care records.
Baseband coax A simple-to-use and inexpensive-to-install
type of coaxial cable that offers a single digital transmission
channel with maximum transmission speeds ranging from 10
million bits per second (bps) up to 150 million bps. Baseband
coax was widely used for LANs and for long-distance transmis-
sion within the telephone network, although much of this coax
has now been replaced by fiber-optic cabling.
Batch processing A mode of transaction processing in which a
group or “batch” of transactions of a particular type is accumulated
and then processed as a single batch at one time. For example, all
sales for a firm would be accumulated during the day and then
processed as a single batch at night.
Baud Number of signals sent per second; one measure of data
transmission speed. Baud is often equivalent to Hertz (another
measure of transmission speed) and to bits per second.
Benchmarking A procedure to compare the capabilities of var-
ious computers in a particular organizational setting by running a
representative set of real jobs (jobs regularly run on the organiza-
tion’s existing computer) on each of the machines and comparing
the resulting elapsed times.
Beta site An organization that is involved in user acceptance
testing of a software package before it is released to the market.
A beta site has influence on fine tuning the package, as well as
possible enhancements for later releases of the software.
Bit Widely used abbreviation for a binary digit, i.e., a 0 or a 1.
Coding schemes used in computer systems employ particular
Glossary 669sequences of bits to represent the decimal numbers, alphabetic
characters, and special characters.
Blade Shorthand for blade server; seeBlade server.
Blade server A server so thin (like a “blade”) that several of
them can be housed in a single chassis, thus saving space in the
computer center. As an example, one particular chassis, which is
less than 16 inches tall, offers up to 14 bays, each of which can
hold a two-processor blade. The blade servers are about 1.2 inches
wide and are mounted vertically in the chassis—much like sliding
a book into a bookshelf. The blade server slides into a bay and
plugs into the chassis, sharing power, fans, floppy drives, switches,
and ports with the other blade servers in the chassis.
Blog A user-generated Web site where entries are made in
journal style; blogs often provide commentary on a particular
subject or serve as a personal online diary.
Bluetooth Short-range radio technology that has been built into
a microchip, enabling data to be transmitted wirelessly at speeds
of 1 million bits per second (bps) up to 24 million bps. Bluetooth
technology eliminates the need for many cables and permits the
control of Bluetooth-equipped appliances from a cellular
phone—all from a remote location, if desired.
Boundary Identifies the scope of a system. A boundary segre-
gates the system from its environment.
BPR SeeBusiness process reengineering.
Bricks-and-clicks A term used for traditional companies
that have integrated their offlineandonlinebusiness channels
as part of a multichannel e-business strategy. See alsoClick-
and-mortar.
Bridge A hardware device employed in a telecommunications
network to connect two local area networks (LANs) or LAN
segments when the LANs use the same protocols, or set of rules.
A bridge is smart enough to forward only messages that need to
go to the other LAN.
Broadband A general designation applied to the higher-speed
alternatives for accessing the Internet from a home or small
office, such as Digital Subscriber Line (DSL), cable modem, and
satellite connections.
Broadband coax A type of coaxial cable—more expensive
and harder to use than baseband coax—that originally used
analog transmission, but increasingly employs digital transmis-
sion. A single broadband coax can be divided into multiple chan-
nels so that a single cable can support simultaneous transmission
of data, voice, and television. Broadband data transmission rates
are similar to those for baseband coax, and high transmission
speeds are possible over much longer distances than are feasible
for baseband coax. Broadband coax is still widely used for cable
television and LANs that span a significant area, often called
metropolitan area networks.
Browser SeeWeb browser.
Bus topology A network topology in which a single length of
cable (i.e., coax, fiber-optic, or twisted pair)—not connected at
the ends—is shared by all network devices; also called a linear
topology.