IBM 8237, Инструкция по установке и эксплуатации

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X- 6
8237 Hub Installation and Planning Guide
km. Kilometer
kVA. Kilovolt ampere. A unit of power.
L
LAN. Local area network.
LAN segment. (1) Any portion of a LAN (for example,
a single bus or ring) that can operate independently but
is connected to other parts of the establishment
network via bridges. (2) An entire ring or bus network
without bridges.
layer. (1) One of the seven levels of the Open
Systems Interconnection reference model. (2) In open
systems architecture, a collection of related functions
that comprise one level of hierarchy of functions. Each
layer specifies its own functions and assumes that
lower level functions are provided. (3) In SNA, a
grouping of related functions that are logically separate
from the functions of other layers. Implementation of
the functions in one layer can be changed without
affecting functions in other layers.
lb. Pound.
LED. Light-emitting diode
link. (1) The logical connection between nodes
including the end-to-end link control procedures. (2)
The combination of physical media, protocols, and
programming that connects devices on a network. (3)
In computer programming, the part of a program, in
some cases a single instruction or an address, that
passes control and parameters between separate
portions of the computer program. (I) (A) (4) To
interconnect items of data or portions of one or more
computer programs. (5) In SNA, the combination of the
link connection and link stations joining network nodes.
link connection. (1) All physical components and
protocol machines that lie between the communicating
link stations of a link. The link connection may include
a switched or leased physical data circuit, a LAN, or an
X.25 virtual circuit. In SNA, the physical equipment
providing two-way communication and error correction
and detection between one link station and one or
more other link stations.
link test. In 10BASE-T and optical fiber based
Ethernet, a signal sent back and forth between a port in
a repeater and a port in an attached device to verify
connection.
local area network (LAN). A computer network
located on a user’s premises within a limited
geographical area.
locally administered address. In a local area
network, an adapter address that the user can assign
to override the universally administered address.
Contrast with universally administered address.
logical connection. In a network, devices that can
communicate or work with one another because they
share the same protocol. See also
physical
connection.
M
m. Meter
MAC. Medium access control.
Management Information Base (MIB). In the Simple
Network Management Protocol (SNMP), a collection of
objects relating to a common management area. See
also
MIB object.
Mbps. One million bits per second.
medium access control (MAC) protocol. In a local
area network, the part of the protocol that governs
communication on the transmission medium without
concern for the physical characteristics of the medium,
but taking into account the topological aspects of the
network, in order to enable the exchange of data
between data stations. (T)
message. (1) A logical partition of the user device’s
data stream to and from the adapter. (2) A group of
characters and control bits transferred as an entity.
MIB. Management Information Base.
MIB browser. A software tool, often shipped with
network management applications, that allows working
with any SNMP MIB that is written in abstract syntax
notation 1 (ASN.1).
MIB object. In the Simple Network Management
Protocol (SNMP), an object contained in the
Management Information Base (MIB).
microcode. (1) One or more microinstructions. (2) A
code, representing the instructions of an instruction set,
that is implemented in a part of storage that is not
program-addressable.
mm. Millimeter.
modem (modulator/demodulator). A device that
converts digital data from a computer to an analog
signal that can be transmitted in a telecommunication
line, and converts the analog signal received to data for
the computer.
N
n-bit byte. A string that consists of n bits. (T)
name. An alphanumeric term that identifies a data set,
statement, program, or cataloged procedure.
NetView. A host-based IBM licensed program that
provides communication network management (CNM)