464743
Specifying and analyzing early requirements in Tropos
We present a framework that supports the formal verification of early requirements specifications. The framework is based on Formal Tropos, a specification language that adopts primitive concepts for modeling early requirements (such as actor, goal, and strategic dependency), along with a rich temporal specification language. We show how existing formal analysis techniques, and in particular model checking, can be adapted for the automatic verification of Formal Tropos specifications. These techniques have been implemented in a tool, called the T-Tool, that maps Formal Tropos specifications into a language that can be handled by the NuSMV model checker. Finally, we evaluate our methodology on a course-exam management case study. Our experiments show that formal analysis reveals gaps and inconsistencies in early requirements specifications that are by no means trivial to discover without the help of formal analysis tools.
12226791
Socio-Intentional Architectures for Multi-Agent Systems: the Mobile Robot Control case
This paper proposes architectural styles for multi-agent systems (MAS) which adopt concepts from organization theory and strategic alliances. These styles are socio-intentional in the sense that they consist of actors who have goals to fulfil and social dependencies describing their obligations. They are represented in i*, a framework designed to model social and intentional primitives and formalized in terms of Formal Tropos. Each proposed style is evaluated with respect to a set of agent software qualities, such as predictability, adaptability and openness. The use of the styles is illustrated and contrasted with a software architecture for mobile robots reported in the literature.
2428324
ST-tool: a CASE tool for security requirements engineering
Security requirements engineering is emerging as a branch of software engineering, spurred by the realization that security must be dealt with early on during the requirements phase. We propose ST-tool, a CASE tool developed for modeling and analyzing functional and security requirements.
661878
Text Mining Through Semi Automatic Semantic Annotation
The Web is the greatest information source in human history. Unfortunately, mining knowledge out of this source is a laborious and error-prone task. Many researchers believe that a solution to the problem can be founded on semantic annotations that need to be inserted in web-based documents and guide information extraction and knowledge mining. In this paper, we further elaborate a tool-supported process for semantic annotation of documents based on techniques and technologies traditionally used in software analysis and reverse engineering for large-scale legacy code bases. The outcomes of the paper include an experimental evaluation framework and empirical results based on two case studies adopted from the Tourism sector. The conclusions suggest that our approach can facilitate the semi-automatic annotation of large document bases.
6610874
Detecting Conflicts of Interest
System vulnerabilities are often caused by the presence of conflicts within the organization where the system-to-be would eventually operate. In particular, conflicts of interest are very harmful since actors can exploit their positions/roles relative to the system for gaining personal advantage. Capturing and resolving such conflicts is a necessary condition for developing secure information systems. In this paper, we show how conflicts of interest can be formally detected during requirements analysis. This allows system designers to investigate the causes for which conflicts may occur in an organization. Thereby, they can better understand the organizational structure and so provide appropriate countermeasures to resolve or at least mitigate them
14238197
Data Semantics Revisited
The problem of data semantics is establishing and maintaining the correspondence between a data source and its intended subject matter. We review the long history of the problem in Databases, and contrast it with recent research on the Semantic Web. We then propose two new directions for research on the problem and sketch some open research questions.
3571148
Requirement Engineering Meets Security: A Case Study on Modelling Secure Electronic Transactions by VISA and Mastercard
Computer Security is one of today’s hot topic and the need for conceptual models of security features have brought up a number of proposals ranging from UML extensions to novel conceptual models. What is still missing, however, are models that focus on high-level security requirements, without forcing the modeler to immediately get down to security mechanisms. The modeling process itself should make it clear why encryption, authentication or access control are necessary, and what are the tradeoffs, if they are selected. In this paper we show that the i*/Tropos framework lacks the ability to capture these essential features and needs to be augmented. To motivate our proposal, we build upon a substantial case study – the modeling of the Secure Electronic Transactions e-commerce suites by VISA and MasterCard – to identify missing modeling features. In a nutshell, the key missing concept is the separation of the notion of offering a service (of a handling data, performing a task or fulfilling a goal) and ownership of the very same service. This separation is what makes security essential. The ability of the methodology to model a clear dependency relation between those offering a service (the merchant processing a credit card number), those requesting the service (the bank debiting the payment), and those owning the very same data (the cardholder), make security solutions emerge as a natural consequence of the modeling process.
12169882
Capturing more world knowledge in the requirements specification
The view is adopted that software requirements involve the representation (modeling) of considerable real-world knowledge, not just functional specifications. A framework (RMF) for requirements models is presented and its main features are illustrated. RMF allows information about three types of conceptual entities (objects, activities, and assertions) to be recorded uniformly using the notion of properties. By grouping all entities into classes or metaclasses, and by organizing classes into generalization (specialization) hierarchies, RMF supports three abstraction principles (classification, aggregation, and generalization) which appear to be of universal importance in the development and organization of complex descriptions. Finally, by providing a mathematical model underlying our terminology, we achieve both unambiguity and the potential to verify consistency of the model.
2515059
Modeling security requirements through ownership, permission and delegation
Security requirements engineering is emerging as a branch of software engineering, spurred by the realization that security must be dealt with early on during the requirements phase. Methodologies in this field are challenging, as they must take into account subtle notions such as trust (or lack thereof), delegation, and permission; they must also model entire organizations and not only systems-to-be. In our previous work we introduced Secure Tropos, a formal framework for modeling and analyzing security requirements. Secure Tropos is founded on three main notions: ownership, trust, and delegation. In this paper, we refine Secure Tropos introducing the notions of at-least delegation and trust of execution; also, at-most delegation and trust of permission. We also propose monitoring as a security design pattern intended to overcome the problem of lack of trust between actors. The paper presents a semantic for these notions, and describes an implemented formal reasoning tool based on Datalog.
14110385
Applying Tropos Methodology to a real case study: Complexity and Criticality Analysis
Currently in Requirements Engineering the attention is being focused more and more on the understanding of a problem by studying the existing organizational setting in which the system will operate. In this paper we present the application of the Tropos early requirements analysis to a real case study, the Ice Co. We introduce a new type of analysis for actor diagrams based on two different parameters, complexity and criticality, and we show the results we obtained during the case study.
8955752
Modeling Social and Individual Trust in Requirements Engineering Methodologies
When we model and analyze trust in organizations or information systems we have to take into account two different levels of analysis: social and individual. Social levels define the structure of organizations, whereas individual levels focus on individual agents. This is particularly important when capturing security requirements where a “normally” trusted organizational role can be played by an untrusted individual. 
 
Our goal is to model and analyze the two levels finding the link between them and supporting the automatic detection of conflicts that can come up when agents play roles in the organization. We also propose a formal framework that allows for the automatic verification of security requirements between the two levels by using Datalog and has been implemented in CASE tool.