Configuring and Managing Host-Based X.25 Links - Edition 5 (36939-90054)

208 Glossary
Glossary
node to node over a defined route
until it reaches its destination.
This technique is referred to as
store and forward. Systems in a
point-to-point network are
connected by means of leased or
dial-up telephone lines. HP 3000
systems attach to the
point-to-point network via
HP 3000 Programmable Serial
Interface (PSI) cards that fit into
the back of each system’s SPU.
NSDIR.NET.SYS Name of the
active network directory file. See
also network directory.
octet An eight-bit byte operated
upon as an entity.
OpenView Admin An
OpenViewWindowsprogram that
enables you to configure how your
OpenView Windows applications
will function. For example, it
enables you to set a default map
for the OpenView DTC Manager.
OpenView Draw An OpenView
Windows program that enables
you to draw the network map,
and to label the components on it.
OpenView DTC Manager
OpenView Windows application
that enables you to configure,
control, monitor, and troubleshoot
the operation of the
Datacommunications and
Terminal Subsystems on the
LAN.
OpenView Run An OpenView
Windows program that covers
most of the control features used
by the DTC Manager, including
monitoring and diagnostic
functions.
OpenView Windows The set of
three programs: OV Admin, OV
Draw and OV Run, running on
the OpenView workstation under
MS Windows, that acts as the
platform for all OpenView
applications, such as DTC
Manager.
OpenView Windows
Workstation The personal
computer that provides software
downloads to enable operation of
the Datacommunications and
Terminal Controller (DTC). The
configuration software that runs
on this workstation is called the
OpenView DTC Manager
software.
OSI model Open Systems
Interconnectionmodel. A modelof
network architecture devised by
the International Standards
Organization (ISO). The OSI
model defines seven layers of a
network architecture, with each
layer performing specified
functions.
packet A block of data whose
maximum length is fixed. The
unit of information exchanged by
X.25 at level 3. There are DATA
packets and various control
packets. A packet type is
identified by the encoding of its
header.