OSI/FTAM Programming Reference Manual

Glossary
HP NonStop OSI/FTAM Programming Reference Manual—528611-001
Glossary-18
OSI (Open Systems Interconnection).
OSI (Open Systems Interconnection). A set of standards used for the interconnection of
heterogeneous computer systems designed for universal connectivity.
OSI address. The address of an object on an OSI network. An OSI address consists of four
components: the transport selector (TSEL), session selector (SSEL), presentation
selector (PSEL), and network service access point (NSAP).
OSI/AS (Application Services). The NonStop implementation of the Session Layer, the
Presentation Layer, and part (ACSE) of the Application Layer of the OSI
Reference Model. The OSI/AS subsystem manages the communication of
messages between a local NonStop system and a remote system on a network. This
subsystem manages the lower-layer services provided by NonStop OSI/TS, X25AM,
and TLAM.
OSI manager process. A process in the OSI/AS subsystem that performs subsystem
management functions. There is one OSI manager process per OSI/AS subsystem.
OSI Reference Model. A communications architecture, adopted by the ISO in 1984, that
includes seven layers that define the functions involved in communications between
two systems, the services required to perform these functions, and the protocols
associated with these services. See also layer.
OSI subsystems. The NonStop subsystems that support the various layers and application
service elements of the OSI Reference Model, including the FTAM subsystem,
APLMGR, OSI/AS, OSI/TS, and TLAM or X25AM.
OSI/TS (Transport Services). The NonStop subsystem that manages the communication
of messages from the Transport Layer on a local NonStop system to the Transport
Layer on a remote system in an OSI network.
owner ID. The identity (Guardian user ID) of the owner of a process on a NonStop system.
parallel associations. Multiple associations running concurrently within a NonStop FTAM
process.
parameter structures. DDL structures that define some of the reference parameters for the
FTM, APS, and MFM procedures.
partially supported file attribute. A virtual filestore (VFS) file attribute, in a supported
storage or security attribute group, for which any reference by the FTAM responder
yields the result that no value is available, and any attempt to change the attribute fails.
In summary, the VFS recognizes the attribute name but provides no value for it.
Contrast with supported file attribute.