Adapting Requirements Specification Techniques for Mobile Information Systems
Abstract
Mobile Information Systems technologies provide capabilities for using/handling information on the move and the motto has become anytime and anywhere computing. Thus, mobility-related requirements have become vital, but many requirements techniques were invented before mobility was so important, thus not focusing on this. The objective of this thesis is to propose adapted techniques for representing mobility-related requirements, both textually and by means of diagram notations. To support textual mobility requirements, the thesis first proposes a taxonomy for mobility-related requirements, then based on this taxonomy it further proposes templates (“boilerplates”) for how to write mobility requirements. Templates are introduced for developing mobility requirements for different mobile applications. Taxonomy with templates were evaluated in a controlled experiment, treatment group finding more requirements than the control group, though not of better quality.
As for diagram notations, the thesis has proposed adaptations to UML activity diagrams and use case diagrams. The main adaptation has been various ways to represent the location context for performing user functions. For use case diagrams, it was also tried to represent equipment usage diagrammatically. Several different visualizations were tried (e.g., annotations, color, pattern fills, symbolic icons) and compared in a series of experiments with student participants.
Specifically, this thesis answers the following four research questions:
RQ1. How can a taxonomy for mobility-related requirements be structured?
RQ2. How can templates be made based on such a taxonomy to help people specify mobility requirements?
RQ3. How can mainstream modelling notations be adapted to include requirements about mobility, such as the user's location and equipment types?
RQ4. What notational adaptations would be the most preferable in terms of task performance and user opinion?
The main contributions of this thesis are:
C1: Taxonomy of mobility related requirements: A taxonomy of mobility-related requirements was developed with four major categories: mobility requirements, mobility system requirements, mobility constraints and mobility data requirements.
C2: Boilerplates for mobility requirements: Based on the taxonomy mentioned, the textual templates were developed and named as requirements boilerplates. The taxonomy-based requirements boilerplates were evaluated in a student experiment.
C3: Adaptations of modelling notations: Various adapted notations were considered for UML Activity Diagrams and Use Case Diagrams. For Activity Diagrams the adaptations considered were several different ways of showing the location of activities. For Use Case Diagrams, adaptations considered both showing location and the equipment used for the use cases. Many possible adaptations were evaluated analytically, and a smaller number were tested experimentally.