Expand Configuration and Management Manual (G06.24+)

Glossary
Expand Configuration and Management Manual—523347-008
Glossary-11
logical device number
logical device number. A number that identifies a particular input-output (I/O) device in the
system.
logical network partitioning. A NonStop TCP/IPv6 feature that allows you to divide the
system into separately-addressed IP subnetworks whereby applications only have
access to a defined set of network interfaces (IP addresses).
logical unit (LU). In the IBM Systems Network Architecture (SNA), a port by which an end
user accesses the network.
LU. See logical unit (LU).
maps exchange. A periodic sharing of network maps information. You can specify a five-
minute interval exchange by setting the network control process modifier
AUTOMATICMAPTIMER. See also distance vector (DV) message.
Measure. A tool used for monitoring the performance of HP systems. Measure can be used
in an Expand network to determine if the network is contributing to performance
problems.
message system. The message system enables the lowest level, fundamental
communication between processes by providing a privileged interface that is trusted
and directly usable only by code running in PRIV mode. Processes must handle
messages from the message system or cause a CPU halt. The file system obeys all
the message system rules on behalf of user applications. The message system also
makes the addressing of processes symbolic (such as \SNAX.$USER).
modified split horizon (MSH). The default routing algorithm provided by the Expand
subsystem. The main advantage of MSH is efficiency: it requires less processing time
than the split horizon (SH) algorithm and avoids loop routing. The main disadvantage
of MSH is that the network may experience temporary discontinuity. See also split
horizon (SH).
modular ServerNet expansion board (MSEB). A ServerNet expansion board (SEB)
that
uses plug-in cards (PICs) to provide a choice of connection media for routing
ServerNet packets.
MSEB. See modular ServerNet expansion board (MSEB)
.
module. A set of components sharing a common interconnection, such as a backplane. A
module is a subset of a group, and it is usually contained in an enclosure. There is
exactly one module in a group.
MPT. See multiple path table (MPT).
MSH. See modified split horizon (MSH).