Internet Protocol (IP). (1) A protocol that routes data
through a network or interconnected networks. IP acts
as an interface between the higher logical layers and
the physical network. However, this protocol does not
provide error recovery, flow control, or guarantee the
reliability of the physical network. IP is a
connectionless protocol. (2) A protocol used to route
data from its source to its destination in an Internet
environment.
inverse ARP. A method for discovering a protocol
address through the known hardware address. In frame
relay, the data link connection identifier (DLCI) is synon-
ymous with the known hardware address.
IP. Internet Protocol.
IPX. Internet Packet Exchange.
ISDN. Integrated services digital network.
KKbps. 1000 bits per second.
LLAN. Local area network.
LED. Light emitting diode.
link. The combination of the link connection (the trans-
mission medium) and two link stations, one at each end
of the link connection. A link connection can be shared
among multiple links in a multipoint or token-ring config-
uration.
lobe. (1) In a star/ring network configuration, two pairs
of conductors that provide separate send and receive
paths between a wiring concentrator and a network
port, such as a wall outlet. (2) In the IBM Token-Ring
Network, the section of cable that attaches a device to
an access unit. The cable can consist of several seg-
ments.
local area network (LAN). (1) A computer network
located on a user’s premises within a limited geograph-
ical area. Communication within a local area network is
not subject to external regulations; however, communi-
cation across the LAN boundary may be subject to
some form of regulation. (T) (2) A network in which a
set of devices are connected to one another for commu-
nication and that can be connected to a larger network.
See also
Ethernet
and
token ring
. (3) Contrast with
metropolitan area network (MAN)
and
wide area
network (WAN)
.
Mmaintenance analysis procedure (MAP). A mainte-
nance document that gives a service representative a
step-by-step procedure for tracing a symptom to the
cause of a failure.
MAN. Metropolitan area network.
management services (MS). Services that assist in
the management of networks in areas such as problem
management, performance and accounting manage-
ment, configuration management, and change manage-
ment.
MAP. Maintenance analysis procedure.
maximum transmission unit (MTU). The largest pos-
sible unit of data that can be sent on a given physical
medium in a single frame. For example, the MTU for
Ethernet is 1500 bytes.
memory. All of the addressable storage space in a
processing unit and other internal storages that is used
to execute instructions.
metropolitan area network (MAN). A network formed
by the interconnection of two or more networks which
may operate at higher speed than those networks, may
cross administrative boundaries, and may use multiple
access methods. (T) Contrast with
local area network
(LAN)
and
wide area network (WAN)
.
MIB. (1) Management information base. (2) MIB
module.
modem (modulator/demodulator). (1) A functional
unit that modulates and demodulates signals. One of
the functions of a modem is to enable digital data to be
transmitted over analog transmission facilities. (T) (A)
(2) A device that converts digital data from a computer
to an analog signal that can be transmitted on a tele-
communication line, and converts the analog signal
received to data for the computer.
monitor. (1) A device that observes and records
selected activities within a data processing system for
analysis. Possible uses are to indicate significant
departure from the norm, or to determine levels of utili-
zation of particular functional units. (T) (2) Software
or hardware that observes, supervises, controls, or veri-
fies operations of a system. (A) (3) In a token-ring
network, the function required to initiate the trans-
mission of a token on the ring and to provide soft-error
recovery in case of lost tokens, circulating frames, or
other difficulties. The capability is present in all ring
stations.
MS. Management services.
X-4 2210 Service and Maintenance