IBM 8285 Nways, Installation And User Manual

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American National Standard Code for Information
Interchange (ASCII). The standard code, using a
coded character set consisting of 7-bit coded characters
(8 bits including parity check), used for information
interchange among data processing systems, data
communication systems, and associated equipment.
The ASCII set consists of control characters and
graphics characters. (A)
ARP. Address Resolution Protocol.
ASCII. American National Standard Code for
Information Interchange.
Asynchronous Transfer Mode (ATM). A transfer
mode in which the information is organized into cells. It
is asynchronous in the sense that the recurrence of cells
containing information from an individual user is not
necessarily periodic.
ATM. Asynchronous Transfer Mode.
ATM campus network. A union of privately-owned
ATM subnetworks interconnected by network node
interfaces (NNIs). See also
network node interface
(NNI).
ATM device. An end system that encapsulates data
into ATM cells and forwards them to the ATM subsystem
across an UNI interface.
ATM subnetwork. A set of ATM subsystems
interconnected by ATM interfaces (UNI, SSI, NNI).
ATM subsystem. The ATM components in an ATM
switch.
attach. To make a device a part of a network logically.
Contrast with
connect, which implies physically
connecting a device to a network.
attenuation. Level of optical power loss expressed in
units of dB.
Authority and Format Identifier. One byte in an ATM
address.
B
bandwidth. (1) The difference, expressed in hertz,
between the highest and the lowest frequencies of a
range of frequencies. For example, analog transmission
by recognizable voice telephone requires a bandwidth of
about 3000 hertz (3 kHz). (2) The bandwidth of an
optical link designates the information-carrying capacity
of the link and is related to the maximum bit rate that a
fiber link can support.
baud. The rate at which signal conditions are
transmitted per second. Contrast with
bits per second
(bps).
BER. Bit error rate.
bit error rate (BER). The ratio of the number of bits
experiencing error on a telecommunications link divided
by the number of bits sent over the link.
bits per second (bps). The rate at which bits are
transmitted per second. Contrast with
baud.
bridge. (1) An attaching device that connects two LAN
segments to allow the transfer of information from one
LAN segment to the other. A bridge may attach the LAN
segments directly by network adapters and software in a
single device, or may connect network adapters in two
separate devices through software and use of a
telecommunications link between the two adapters.
(2) A functional unit that connects two LANs that use the
same logical link control (LLC) procedures but may use
the same or different medium access control (MAC)
procedures. (T)
Contrast with gateway and router.
broadband. A frequency band divisible into several
narrower bands so that different kinds of transmissions
such as voice, video, and data transmission can occur at
the same time. Synonymous with
wideband.
broadcast. Simultaneous transmission of data to more
than one destination.
buffer. (1) A portion of storage used to hold input or
output data temporarily. (2) A routine or storage used to
compensate for differences in data rate or time of
occurrence of events, when transferring data from one
device to another. (A)
bus. (1) In a processor, a physical facility on which
data is transferred to all destinations, but from which
only addressed destinations may read in accordance
with appropriate conventions. (I) (2) A network
configuration in which nodes are interconnected through
a bidirectional transmission medium. (3) One or more
conductors used for transmitting signals or power. (A)
BUS. Broadcast and Unknown Server.
byte. (1) A string that consists of a number of bits,
treated as a unit, and representing a character. (T) (2) A
binary character operated upon as a unit and usually
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IBM 8285 Nways ATM Workgroup Switch: Installation and User’s Guide