SEON: Networked Ontology Specification

Runtime Requirements Ontology (RRO)

1. Ontology Description

The Runtime Requirements Ontology (RRO) focuses on the notions related to the use of Requirements at Runtime. The Program Execution sub-ontology focuses on capturing the ontological nature of program execution, which is the basis for the use of requirements at runtime. The Runtime Requirements sub-ontology addresses the use of Runtime Requirements Artifacts by programs in execution.

2. Related Ontologies

Networked ontologies used by RRO:

3. Ontology Models

3.1. Program Execution

The Program Execution subontology focuses on capturing the ontological nature of program execution, which is the basis for the use of requirements at runtime.

Figure 1 presents the conceptual model of the RRO - Program Execution subontology.

Figure 1. RRO - Program Execution conceptual model.

A Program is defined as a Software Item, a piece of software, produced during the software process, not considered a complete Software Product, but which aims at producing a certain result through execution on a computer, in a particular way, given by the Program Specification. In other words, a Program intends to implement a Program Specification, that intends to satisfy a set of Requirement Artifacts. Thus, we can say that there is a relation between Program and Requirement Artifact that is derived from the existing relation between Program Specification and Requirement Artifact.

A Loaded Program Copy is the materialization of a Program, inhering in a Machine. The Loaded Program Copy is a complex Disposition that is constituted by one or more Software Functions, which are, in turn, instances of Software Function Universals. When the software development process is accomplished correctly, the Software Functions that constitute the (loaded) program copy are instances of the exact Software Function Universals described by the Program Specification and successfully implemented by the Program.

Program Copy Execution is an Event representing the execution of the Loaded Program Copy running in a Machine, i.e., the Program Copy Execution is the event of the physical manifestation of the dispositions, represented as the complex disposition Loaded Program Copy, that inhere in the Machine. In this context, the Machine participates in the Program Copy Execution playing the role of Controller.

A Program Copy Execution, as an event, brings about a particular situation, said an Observable State. An Observable State is a situation resulting from the execution of a program copy.

3.2. Runtime Requirements

The Runtime Requirements sub-ontology addresses the use of Runtime Requirements Artifacts by programs in execution.

Figure 2 presents the conceptual model of the RRO - RTR subontology.

Figure 2. RRO - RTR conceptual model.

The first important distinction in the Runtime Requirements sub-ontology is between Runtime Requirement Artifacts, those that can be used by Program Copy Executions at runtime, from their non-runtime counterparts, named Design Time Requirement Artifacts.

Runtime Requirement Artifact is further specialized into two specific subtypes: Monitoring Runtime Requirement Artifact defines the criteria for verifying if a requirement is being satisfied or not at runtime; on the other hand, Change Runtime Requirement Artifact specifies changes on the system’s behavior, in order for the software system to keep fulfilling the goals it has been designed for.

An RRT Program is a Program that is built intending to satisfy at least one Runtime Requirement Artifact. The aforementioned distinction between runtime requirement artifacts also reflects in RRT Programs (and in the corresponding Loaded Program Copies that materialize them and in the Program Copy Executions that are executions of the latter). Thus, RRT Program is specialized in Compliance Program, representing those RRT Programs that intend to satisfy at least one Monitoring Runtime Requirement Artifact, and Adaptation Program, representing those RRT Programs that intend to satisfy at least one Change Runtime Requirement Artifact. The generalization set of RRT Program is not disjoint, since the same program can intend to satisfy, at the same time, both a Monitoring Runtime Requirement Artifact and a Change Runtime Requirement Artifact. Finally, some RRT Programs are built to act over (monitor/change) specific programs. When a Program is the target of an RRT Program, we say that it plays the role of a Target Program.
A Loaded RRT Program Copy is the materialization of an RRT Program, while an RRT Program Copy Execution is the execution of a Loaded RRT Program Copy. An RRT Program Copy Execution uses Runtime Requirement Artifacts as resources. A Compliance Program Copy Execution uses Monitoring Runtime Requirement Artifacts, and monitors Observable States produced by another Program Copy Execution, said Target Program Copy Execution. While using requirements at runtime, we are not interested in situations arising from the execution of any program, but only in those arising from the Target Program Copy Executions. For this reason, a Compliance Program Copy Execution monitors Target Execution States, i.e, the situations arising from the Target Program Copy Execution. The Compliance Program Copy Execution monitors the Target Execution States to verify if the runtime requirements comply with the criteria specified in the Monitoring Runtime Requirement Artifacts. If one or more requirements are not being fulfilled accordingly, an Adaptation Program Copy Execution can trigger changes in the the Loaded Program Copy being monitored, which is said a Loaded Target Program Copy, by using Change Runtime Requirement Artifacts. Like the RRT Program generalization set, the generalization set of RRT Program Copy Execution (and also of Loaded RRT Program Copy) is not disjoint, since the same RRT Program Copy Execution can use, at the same time, both a Monitoring Runtime Requirement Artifact and a Change Runtime Requirement Artifact.

4. Concepts Definition

The following table shows the definitions for RRO concepts.

Concept	Definition
Adaptation Program	An Adaptation Program is a RRT Program that intends to satisfy at least one Change Runtime Requirement Artifact.
Adaptation Program Copy Execution	An Adaptation Program Copy Execution is the execution of a Loaded Adaptation Program Copy. It uses Change Runtime Requirement Artifacts as resources to triggers changes in its Loaded Target Program Copy.
Change Runtime Requirement Artifact	Change Runtime Requirement Artifact specifies changes on the system's behavior, in order for the software system to keep fulfilling the goals it has been designed for.
Compliance Program	Compliance Program is a RRT Program that intends to satisfy at least one Monitoring Runtime Requirement Artifact.
Compliance Program Copy Execution	A Compliance Program Copy Execution is the execution of a Loaded Compliance Program Copy. It uses Monitoring Runtime Requirement Artifacts as resources to monitor Execution States.
Controller	A Machine where a Loaded Program Copy is running (Program Copy Execution) plays the role of Controller.
Design Time Requirement Artifact	Design Time Requirement Artifact is a Requirement Artifact written in natural language or other format that could not be processed by a program at runtime. It is a Requirement Artifact to be used during design time.
Loaded Adaptation Program Copy	Loaded Adaptation Program Copy is the materialization of an Adaptation Program.
Loaded Compliance Program Copy	Loaded Compliance Program Copy is the materialization of a Compliance Program.
Loaded Program Copy	Loaded Program Copy is the materialization of a Program, inhering in a Machine. Ex.: a copy of a program loaded in primary memory of my computer.
Loaded RRT Program Copy	Loaded RRT Program Copy is the materialization of a RRT Program.
Loaded Target Program Copy	Loaded Target Program Copy is the materialization of a Target Program.
Machine	Machine is a hardware equipament able to run programs.
Monitoring Runtime Requirement Artifact	Monitoring Runtime Requirement Artifact defines the criteria for verifying if a requirement is being satisfied or not at runtime.
Observable State	Observable State is a situation resulting from the execution of a program copy. It involves qualities and quality values (qualia) of the Machine in which the Loaded Program Copy inheres, as well as of entities residing in that Machine (including the Loaded Program Copy itself).
Program Copy Execution	Program Copy Execution is an Event representing the execution of the Loaded Program Copy running in a Machine. In other words, the Program Copy Execution is the event of the physical manifestation of the dispositions (represented as the complex disposition Loaded Program Copy) that inhere in the Machine.
RRT Program	An RRT Program is a Program that is built intending to satisfy at least one Runtime Requirement Artifact.
RRT Program Copy Execution	An RRT Program Copy Execution is the execution of a Loaded RRT Program Copy. It uses Runtime Requirement Artifacts as resources.
Runtime Requirement Artifact	Runtime Requirement Artifact is a Requirement Artifact written in a computational file that could be processed by a program at runtime (RRT Program Copy Execution).
Software Function	Software Functions are functional dispositions that constitute the complex disposition Loaded Program Copy. Each Software Function is an instance of a Software Function Universal. When the software development process is accomplished correctly, the Software Functions that constitute the Loaded Program Copy are instances of the exact Software Function Universals described by the Program Specification and successfully implemented by the Program.
Target Execution State	Execution State is the Observable State resulting from the Target Program Copy Execution, which is monitored by some Compliance Program Copy Executions.
Target Program	Target Program is the role a Program plays when it is the targer of a RRT Program, i.e., the RRT Program are built to act over (monitor/change) the Target Program.
Target Program Copy Execution	A Target Program Copy Execution is the execution of a Loaded Target Program Copy. It brings about to an Execution State.

Detailed Concepts