OSI/TS SCF Reference Manual

Glossary
OSI/TS SCF Reference Manual—424832-001
Glossary-10
subnetwork
connection; it can be dynamically created and deleted or it can be reused after the
connection is released. A ViewPoint subdevice corresponds to an X.25 network virtual
circuit. Tandem LAN Access Method (TLAM) subdevices are of several types: FSAPs,
ports, services, domains, workstations, windows, and gateways [for G06 and above
release, Port Access Method (PAM)
subdevices correspond to PAM ports].
subnetwork. One or more intermediate systems that provide relaying and through which end
open systems may establish network connections.
subnetwork dependent convergence function (SNDCF). A function in the network service
provider (NSP) process that allows the OSI Internet protocol (which usually operates
over LANs) to operate over other protocols, such as X.25.
subnetwork point of attachment (SNPA). A real, physical address, identifying the point of
attachment to a subnetwork. An OSI end system can be connected to one subnetwork or
to a number of different subnetworks:
subsystem. (1) The software and/or hardware facilities that provide users with access to a set
of communications services. (2) In Distributed Systems Management (DSM)
, a program
or set of processes that manages a cohesive set of objects. Each subsystem has a process
through which applications can request services by issuing commands defined by that
subsystem; in some cases, this process is the entire subsystem. Many subsystems also
have interactive interface.
Subsystem Control Facility (SCF). A Distributed Systems Management (DSM)
facility that
allows system managers to make online changes to the configuration of devices and
controllers. SCF is a part of DSM, used to provide a common, interactive management
interface for configuring, controlling, and collecting information from Compaq data
communications products.
Subsystem Control Point (SCP). In Distributed Systems Management (DSM)
, the
management process for all Compaq data communications subsystems. There can be
several instances of this process. Applications using SPI send all commands for data
communications subsystems to an instance of this process, which in turn sends the
commands on to the manager processes of the target subsystems. SCP also processes a
few commands itself. It provides security features, version compatibility, support for
tracing, and support for applications implemented as NonStop process pairs.
Subsystem ID (SSID). In Distributed Systems Management (DSM)
programmatic interfaces,
a data structure that uniquely identifies a subsystem to SPI. It consists of the name of the
owner of the subsystem (such as Compaq), a subsystem number that identifies that
particular subsystem, and a subsystem version number. The SSID is an argument to most
of the subsystem procedures.
Subsystem Programmatic Interface (SPI). In Distributed Systems Management (DSM)
, a
set of procedures and associated definition files used to define common message-based
programmatic interfaces for communication between requesters and servers—for
instance, in a management application. SPI includes procedures to build and decode
specially formatted messages; definition files in Pascal, TAL, C, COBOL85, and TACL