NonStop S-Series Hardware Installation and FastPath Guide (G06.26+)

Glossary
HP NonStop S-Series Hardware Installation and FastPath Guide—529876-001
Glossary-74
open system
open system. A system with interfaces that conform to international computing standards
and therefore appear the same regardless of the system’s manufacturer. For example,
the Open System Services (OSS) environment on HP NonStop™ systems conforms to
international standards such as ISO/IEC IS 9945-1:1990 (ANSI/IEEE Std. 1003.1-
1990, also known as POSIX.1), national standards such as FIPS 151-2, and portions
of industry specifications such as the X/Open Portability Guide Version 4 (XPG4).
Open System Services (OSS). An open system environment available for interactive or
programmatic use with the HP NonStop™ operating system. Processes that run in the
OSS environment usually use the OSS application program interface. Interactive users
of the OSS environment usually use the OSS shell for their command interpreter.
Synonymous with Open System Services (OSS) environment. Contrast with Guardian.
Open System Services (OSS) environment. The HP NonStop™ Open System Services
(OSS) application program interface (API), tools, and utilities.
Open System Services (OSS) Monitor. A Guardian utility that accepts commands affecting
OSS objects through an interactive Guardian interface named the Subsystem Control
Facility (SCF).
Open System Services (OSS) signal. A signal model defined in the POSIX.1 specification
and available to processes in the OSS environment. OSS signals can be sent between
processes.
Open Systems Interconnection (OSI). A seven-layer network architecture model defined
by the International Organization for Standardization (ISO). The two lowest layers deal
with the physical connections and their protocols. The five upper layers deal with
network services, such as network file transfers and access to remote databases.
Open Systems Interconnection Layer 2. The data-link control level of the Open Systems
Interconnection (OSI) model, composed of asynchronous or minimal line control
protocols, byte-oriented or character-oriented protocols, and bit-synchronous or
bit-oriented protocols. Data link protocols can be defined in terms of method of access
of data, link relationship of stations, error detection scheme, error recovery, message
formatting, logical half-duplex or full-duplex operation, code, and machine
transparency.
operating system. See HP NonStop™ operating system.
operating system image. See OSIMAGE.
operational environment. The conditions under which your system performs. These
conditions include the devices and communications lines that are made active and the
system and application processes that are started at system startup.
operator. (1) A symbol, such as an arithmetic or conditional operator, that performs a
specific operation on operands. (2) In Network Control Language (NCL), a lexical
element used for working on terms in expressions. The five types of operators are
parenthetical, arithmetic, Boolean, relational, and string. (3) For an HP NonStop™