Between Dec 19, 2024 and Jan 2, 2025, datasets can be submitted to DRUM but will not be processed until after the break. Staff will not be available to answer email during this period, and will not be able to provide DOIs until after Jan 2. If you are in need of a DOI during this period, consider Dryad or OpenICPSR. Submission responses to the UDC may also be delayed during this time.
 

A Reference Model For Hierarchical Requirements

Loading...
Thumbnail Image

Persistent link to this item

Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

A Reference Model For Hierarchical Requirements

Published Date

2020-01

Publisher

Type

Thesis or Dissertation

Abstract

Reference models such as Parnas' Four Variable model, Jackson's World-Machine model, and Gunther et al.'s WRSPM model abstractly define and relate key artifacts in requirements engineering. In the past decades, when systems were typically defined and developed in the traditional top-down way, these models were enormously useful for engineers to rigorously define and analyze their requirements. However, nowadays these models don't seem to be as helpful in discussing the requirements of systems. Modern systems are developed in a hierarchical, middle-out and distributed manner; i.e. starting from candidate architectures, they are iteratively composed using a set of existing or newly developed subsystems. This has necessitated the need for engineers to define requirements at progressively varying levels of scope within the system, hierarchically co-evolve those requirements with the architecture, and apportion them to parts of the system such that each part is independently governable, yet composable. Unfortunately, hierarchically scoping, defining and reasoning about requirements and architecture in an intertwined manner is both a conceptually and methodologically challenging task. While the use of reference models have been a time-honored approach to systematically address such challenges, none of the existing models discuss the notion of hierarchy or the co-evolution between requirements and architecture. Nevertheless, capturing this hierarchical, co-evolutionary relationship in a generic framework such as a reference model, we believe, will be practically helpful for engineers. In this dissertation, we define the hierarchical requirements reference model that abstractly, yet formally, explains the "Twin Peaks" of requirements and architecture. The goal of this model is to provide an unambiguous framework---a set of vocabulary and rules---that engineers can use as a frame of reference to rigorously discuss these artifacts in real system developments. Central to this model is the notion of hierarchy that weaves together the requirements and architecture in a way that naturally allows understanding their attributes and relationships as well as addressing the related challenges. Further, we define a new formal definition of traceability based on the hierarchical satisfaction relationship. This way of formally defining traceability allowed us to formulate the notion of "complete traceability"---the ability to identify all possible satisfaction trace links between requirements. Further, it helped bring out the distinction between "necessary" vs. "sufficient" sub-systems' requirements to achieve a system-level requirement. This new insight into traceability, we believe, will greatly help engineers manage the requirements of large complex systems. To illustrate the practicality of this model, we use an infusion pump case example system ---an industrial case study from the medical domain. Using a model-based approach we describe how the concepts defined in this new reference model help rigorously define and reason about the device's hierarchic requirements and architecture. As we illustrate, we also describe our novel enhancements/extensions to existing requirements techniques and tools to allow requirements capture and analysis. While the specifics of this illustration, such as the use of formal methods-based tools and techniques are particular to the case example considered, the reference model concepts are applicable to both formal and informal requirements engineering of modern, complex systems.

Keywords

Description

University of Minnesota Ph.D. dissertation.January 2020. Major: Computer Science. Advisor: Mats Heimdahl. 1 computer file (PDF); xi, 166 pages.

Related to

Replaces

License

Collections

Series/Report Number

Funding information

Isbn identifier

Doi identifier

Previously Published Citation

Other identifiers

Suggested citation

Murugesan, Anitha. (2020). A Reference Model For Hierarchical Requirements. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/213089.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.