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Back end The server part of a client/server application. It provides services across
the network that have been requested by the client. For example, a back end may be
a database server that responds to SQL requests from a workstation running a front
end application.
Back-up A duplicate copy of data places in a separate, safe place electronic storage,
on tape, on a disk, in a vault to guard against total loss in the event the original data
some how becomes inaccessible.
Back-up server Software or hardware which copies files so that there are always
two current copies of each file. Also known as a shadow server.
Backbone A high-capacity network that links together other networks of lower
capacity. A local backbone network would typically be an FDDI network acting as an
in building backbone to link together multiple LANs. A wide area backbone network
would typically use digital leased circuits and multiplexers or routers.
Background Task or Mode A secondary function perforated by a computer without
interrupting its current or primary task.
Back-up domain controller A server in a network domain that keeps and uses a
copy of the domain’s user accounts database to validate logon requests.
Bandwidth The range of frequencies a transmission line or channel can carry: the
greater the bandwidth, the greater the information - carrying capacity of a channel.
For a digital channel this is defined in bit/s. For an analog channel it is dependent on
the type and method of modulation used to encode the data.
10Base2 A form of Ethernet and IEEE 802.3 network cabling using thin coaxial. It
refers to 10Mbit/s speed Baseband transmission over 200 meters maximum length
in practice 185m) and is commonly known as Cheapernet.
10Base5 A form of Ethernet and IEEE 802.3 network cabling using thick coax. It
refers to 10Mbit/s speed Baseband transmission and 500m maximum length.