Title of talk: Challenges in modelling and analyzing quantitative aspects of a bike-sharing product line

Abstract

Within the recently started EU project Quanticol, a side-study aimed at scalable quantitative analysis of collective adaptive systems (CAS) has been foreseen. The nature of CAS, together with the importance of the societal goals they address, mean that it is imperative to carry out thorough analyses of their design to investigate all aspects before they are put into operation. In this context it is important to realize that the behaviour of the individual system components from which a CAS is composed, may exhibit variability not only in the kind of features but also in the quantitative characteristics of features themselves. Starting form one of the case studies identified in Quanticol, on bicycle sharing, we have started to apply variability analyses on a family of bike-sharing systems (BSS) that we have defined. First we have sought support in available tools for the possibility of adding attributes and quantitative characteristics to our BSS specification. This has resulted in a tool chain that includes (academic) tools that provide different functionalities regarding the analysis of software product lines, from feature modelling to product derivation, to quantitative evaluation of the attributes of products, and, finally, to behavioural variability analysis. This latter activity has subsequently led us to extend VMC, our modelling and verification environment based on the use of modal transition systems as semantic model, with the possibility to pass values in the specifications.