Configuring and Managing Host-Based X.25 Links - Edition 6 (36939-90057)

Glossary
M bit
Glossary
227
LCI Logical Channel Identifier. Local value on a
network node which identifies the channel used to
establish a virtual circuit (SVC or PVC) through an
X.25 network.
ldev See logical device number.
leased line Data-grade telephone line leased
directly to a subscriber and allocated specifically for
the subscriber’s needs.
line speed Speed at which data is transferred over
a specific physical link (usually measured in bits or
kilobits per second).
link name The name that represents a hardware
interface card. The link name can contain as many
as eight characters. All characters except the first
can be alphanumeric; the first character must be
alphabetic.
Local Area Network Interface Controller
(LANIC) A hardware card that fits into the
backplane of the HP 3000 Series 900 computer and
provides a physical layer interface for local area
networks.
local connection See direct connection.
local node The computer that you are configuring
or that you are logged on to.
local switching Feature of the DTC which permits
back-to-back configuration (for connections to an HP
3000 MPE/V host), using two ports of the same DTC.
local user group A list defined for a particular
DTC and card that specifies which remote nodes this
DTC can send data to and also which remote nodes
this DTC can receive data from. (See also Closed
User Group).
logging The process of recording the usage of
network resources. Events can be logged to both the
OpenView workstation and to the MPE host.
logging class A number defining the severity of any
given event logged. An operator uses the logging
classes to specify which events are to be logged.
Class 1 (catastrophic event) is always logged.
logical device number (ldev) A value by which
the operating system recognizes a specific device. All
DTC devices that are configured as nailed devices
through the NMMGR configuration have ldev
numbers permanently assigned. The DTC devices
can then be accessed programmatically through use
of their ldev number. Non-nailed devices have ldev
numbers that are assigned from a pool of available
ldev numbers for the life of their connection to a
system. You cannot access non-nailed devices
programmatically.
log off The termination of a job or session.
log on The process of initiating a job or session.
logon device See session-accepting device.
loopback The routing of messages from a node back
to itself.
LUG See local user group.
maintenance mode An NMMGR character mode
interface used to manage both network directory and
configuration files. It can be used interactively, from
within the screen mode interface, or as a set of
commands entered via a batch job.
map, network A drawing that shows the topology
of the network. For networks managed by the
OpenView DTC Manager, a network map must be
created through use of the OVDraw capability
provided with the management software. A network
map is also a hardcopy drawing used when planning
a network. It shows network topology, node and
network names, addresses, network boundaries (for
an internetwork map), and link types.
mapping A set of characteristics that describe a
route taken by messages to reach a destination node.
This set of characteristics is configured with
NMMGR at every node on a point-to-point network.
One mapping is configured at each node for every
other node on the network to which messages will be
sent.
MAU See medium attachment unit.
M bit More data bit. Setting this bit in a DATA
packet indicates that at least one more DATA packet
is required to complete a message of contiguous
data.