Modeling and analyzing variability for mobile information systems

Abstract. Advances in size, power, and ubiquity of computing, sensors, and communication technology made possible the development of mobile or nomadic information systems. Variability of location and system behavior is a central issue in mobile information systems, where behavior of software has to change and re-adapt to the different location settings. This paper concerns modeling and analysis of the complementary relation between software and location variability. We use graphical and formal location modeling techniques, show how to elicit and use location model in conjunction with Tropos goal-oriented framework, and introduce automated analysis on the location-based models.

Goal-based self-contextualization

Abstract. System self-contextualizability is the system ability to autonomously adapt its behavior to the uncontrollable relevant context to keep its objectives satisfied. Self-contextualizable system must have alternative behaviors each fitting to a set of contexts. We propose to start considering context at the level of requirements engineering, adopting Tropos goal model to express requirements and complementing it with our proposed context analysis. We define variation points on goal model where a context-based decision might need to be taken, and propose constructs to analyze context. While goal analysis provides constructs to hierarchically analyze goals and discover alternative sets of tasks to be executed to satisfy a goal, our proposed context analysis provides constructs to hierarchically analyze context and discover alternative sets of facts to be monitored to verify a context.

Location-based software modeling and analysis: Tropos-based approach

Abstract. The continuous growth of interest in mobile applications makes the concept of location essential to design and develop software systems. Location-based software is supposed to be able to monitor the surrounding location and choose accordingly the most appropriate behavior. In this paper, we propose a novel conceptual framework to model and analyze location-based software. We mainly focus on the social facets of locations adopting concepts such as actor, resource, and location-based behavior. Our approach is based on Tropos methodology and allows the analyst to elicit and model software requirements according to the different locations where the software will operate. We propose an extension of Tropos modeling and adapt its process to suit well with the development of location-based software. The proposed framework also includes automated analysis techniques to reason about the relation between location and location-based software.

A Goal Modeling Framework for Self-contextualizable Software

Abstract. Self-contextualizability refers to the system ability to autonomously adapt its behaviour to context in order to maintain its objectives satisfied. In this paper, we propose a modeling framework to deal with self-contextualizability at the requirements level. We use Tropos goal models to express requirements; we provide constructs to analyse and represent context at each variation point of the goal model; and we exploit the goal and context analysis to define how the system satisfies its requirements in different contexts. Tropos goal analysis provides constructs to hierarchically analyse goals and discover alternative sets of tasks the system can execute to satisfy goals; our framework extends Tropos goal model by considering context at its variation points, and provides constructs to hierarchically analyse context and discover alternative sets of facts the system has to monitor to verify a context. A self-contextualizable promotion information system scenario is used to illustrate our approach. Key words: GORE, Context Analysis, Self-Contextualization