Context for goal-level product line derivation

Product line engineering aims at developing a family of products and facilitating the derivation of product variants from it. Context can be a main factor in determining what products to derive. Yet, there is gap in incorporating context with variability models. We advocate that, in the first place, variability originates from human intentions and choices even before software systems are constructed, and context influences variability at this intentional level before the functional one. Thus, we propose to analyze variability at an early phase of analysis adopting the intentional ontology of goal models, and studying how context can influence such variability. Below we present a classification of variation points on goal models, analyze their relation with context, and show the process of constructing and maintaining the models. Our approach is illustrated with an example of a smarthome for people with dementia problems. 1

A situational approach for the definition and tailoring of a data-driven software evolution method

Successful software evolution heavily depends on the selection of the right features to be included in the next release. Such selection is difficult, and companies often report bad experiences about user acceptance. To overcome this challenge, there is an increasing number of approaches that propose intensive use of data to drive evolution. This trend has motivated the SUPERSEDE method, which proposes the collection and analysis of user feedback and monitoring data as the baseline to elicit and prioritize requirements, which are then used to plan the next release. However, every company may be interested in tailoring this method depending on factors like project size, scope, etc. In order to provide a systematic approach, we propose the use of Situational Method Engineering to describe SUPERSEDE and guide its tailoring to a particular context.Peer ReviewedPostprint (author's final draft

Life event ontology based e-government service integration with privacy awareness

University of Technology Sydney. Faculty of Engineering and Information Technology.The advancement of information and communications technology (ICT) and web services offers a promising opportunity for e-government service integration, which can improve the availability and quality of e-government services. One of the key challenges in electronic government (e-government) is the composition of standalone e-government services to achieve complex services. In recent years, the life event model as ontology has been introduced as the core element of integrating complexity of service delivery to improve the efficiency and reusability of e-government services, and web-based information management systems. Despite the conceptual emergence of life event ontology, the question as to how ontology can be used to effectively model life events to support e-government government to citizen service integration remains. Furthermore, privacy concerns represents a major barrier for citizens to accept e-government services, and the question of how to address these privacy issues is becoming increasingly important as the government moves to push service delivery online. Although solutions have been recently suggested in the literature to deal with privacy concerns, there are few practical approaches for helping citizens to create their preferences for privacy protection based on various aspects of privacy policy. These preferences include purpose, retention, consent and the protection of personal information in the context of using e-government services. As a step forward to satisfy the above requirements and to address some of the current challenges, this thesis presents a new framework for supporting e-government service integration based on a life event model. More specifically, the framework enables the system to automatically discover, select, compose and execute correct service across multiple web applications for appropriate life events and to allow a citizen to set up their privacy preferences and to support computerisation of these preferences so that these preferences can be guaranteed. The main contributions are fivefold: (i) the proposal of a conceptual framework of e-government service integration based on life events, (ii) the development of a new life-event model using ontology technique and the methodology to model life events as an ontology model for e-government service integration, (iii) the development of a novel citizen personal information sensitivity model with privacy awareness for supporting citizens in expressing their privacy preferences and for granting the protection of citizens’ personal information, (iv) the development of a suite of techniques to implement the framework including a practical solution to enforce the privacy policies in relation to citizens’ personal information during e-government service integration, and (v) the manifestation of the validity of the proposed framework, models and techniques through the creation of a working prototype of an integrated e-government service system in a specific e-government domain in Saudi Arabia. The significance of this study can be seen from the fact that it: (i) enables the domain expert to model effective life-events based on the use of ontology building methodology, (ii) enables effective modeling of citizens’ personal information, (iii) enables citizens to specify their privacy preferences, (iv) ensures that citizens can be well informed in terms of what information is used, what purpose is it used for, where and how it is stored and who will handle the information, and (v) enforces privacy policies which correspond to the citizens’ privacy preferences so that their privacy concerns can be properly addressed and that citizens’ personal information will be protected and guaranteed against unauthorized access, loss, misuse or alterations based on their privacy preferences. Based on the outcomes of this study, the integrated e-government systems can significantly improve the accessibility of e-government services and enhance the citizens' trust toward the integrated government e-service systems

Semantic validation of affinity constrained service function chain requests

Network Function Virtualization (NFV) has been proposed as a paradigm to increase the cost-efficiency, flexibility and innovation in network service provisioning. By leveraging IT virtualization techniques in combination with programmable networks, NFV is able to decouple network functionality from the physical devices on which they are deployed. This opens up new business opportunities for both Infrastructure Providers (InPs) as well as Service Providers (SPs), where the SP can request to deploy a chain of Virtual Network Functions (VNFs) on top of which its service can run. However, current NFV approaches lack the possibility for SPs to define location requirements and constraints on the mapping of virtual functions and paths onto physical hosts and links. Nevertheless, many scenarios can be envisioned in which the SP would like to attach placement constraints for efficiency, resilience, legislative, privacy and economic reasons. Therefore, we propose a set of affinity and anti-affinity constraints, which can be used by SPs to define such placement restrictions. This newfound ability to add constraints to Service Function Chain (SFC) requests also introduces an additional risk that SFCs with conflicting constraints are requested or automatically generated. Therefore, a framework is proposed that allows the InP to check the validity of a set of constraints and provide feedback to the SP. To achieve this, the SFC request and relevant information on the physical topology are modeled as an ontology of which the consistency can be checked using a semantic reasoner. Enabling semantic validation of SFC requests, eliminates inconsistent SFCs requests from being transferred to the embedding algorithm.Peer Reviewe

Modelling Requirements for Content Recommendation Systems

This paper addresses the modelling of requirements for a content Recommendation System (RS) for Online Social Networks (OSNs). On OSNs, a user switches roles constantly between content generator and content receiver. The goals and softgoals are different when the user is generating a post, as opposed as replying to a post. In other words, the user is generating instances of different entities, depending on the role she has: a generator generates instances of a "post", while the receiver generates instances of a "reply". Therefore, we believe that when addressing Requirements Engineering (RE) for RS, it is necessary to distinguish these roles clearly. We aim to model an essential dynamic on OSN, namely that when a user creates (posts) content, other users can ignore that content, or themselves start generating new content in reply, or react to the initial posting. This dynamic is key to designing OSNs, because it influences how active users are, and how attractive the OSN is for existing, and to new users. We apply a well-known Goal Oriented RE (GORE) technique, namely i-star, and show that this language fails to capture this dynamic, and thus cannot be used alone to model the problem domain. Hence, in order to represent this dynamic, its relationships to other OSNs' requirements, and to capture all relevant information, we suggest using another modelling language, namely Petri Nets, on top of i-star for the modelling of the problem domain. We use Petri Nets because it is a tool that is used to simulate the dynamic and concurrent activities of a system and can be used by both practitioners and theoreticians.Comment: 28 pages, 7 figure