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.
6310113
Requirements Engineering Meets Trust Management: Model, Methodology, and Reasoning
The last years have seen a number of proposals to incorporate Security Engineering into mainstream Software Requirements Engineering. However, capturing trust and security requirements at an organizational level (as opposed to a design level) is still an open problem. This paper presents a formal framework for modeling and analyzing security and trust requirements. It extends the Tropos methodology, an agent-oriented software engineering methodology. The key intuition is that in modeling security and trust, we need to distinguish between the actors that manipulate resources, accomplish goals or execute tasks, and actors that own the resources or the goals. To analyze an organization and its information systems, we proceed in two steps. First, we built a trust model, determining the trust relationships among actors, and then we give a functional model, where we analyze the actual delegations against the trust model, checking whether an actor that offers a service is authorized to have it. The formal framework allows for the automatic verification of security and trust requirements by using a suitable delegation logic that can be mechanized within Datalog. To make the discussion more concrete, we illustrate the proposal with a Health Care case study.
6657466
Local Relational Model: A Logical Formalization of Database Coordination
We propose a new data model intended for peer-to-peer (P2P) databases. The model assumes that each peer has a (relational) database and exchanges data with other peers (its acquaintances). In this context, one needs a data model that views the space of available data within the P2P network as an open collection of possibly overlapping and inconsistent databases. Accordingly, the paper proposes the Local Relational Model, develops a semantics for coordination formulas. The main result of the paper generalizes Reiter's characterization of a relational database in terms of a first order theory [1], by providing a syntactic characterization of a relational space in terms of a multi-context system. This work extends earlier work by Giunchiglia and Ghidini on Local Model Semantics [2].
1423082
Data Management for Peer-to-Peer Computing : A Vision
We motivate special database problems introduced by peer-to-peer computing and propose the Local Relational Model (LRM) to solve some of them. As well, we summarize a formalization of LRM, present an architecture for a prototype implementation, and discuss open research questions.
38499377
The Tropos Software Development Methodology: Processes, Models and Diagrams
Tropos is a novel agent-oriented software development methodology founded on two key features: (i) the notions of agent, goal, plan and various other knowledge level concepts are fundamental primitives used uniformly throughout the software development process; and (ii) a crucial role is assigned to requirements analysis and specification when the system-to-be is analyzed with respect to its intended environment. This paper describes the basic concepts on which Tropos is founded and the types of models one builds out of them. We also specify the analysis process through which design flows from external to system actors through a goal analysis and delegation. In addition, we provide an abstract syntax for Tropos diagrams and other linguistic constructs.
3507397
A knowledge level software engineering methodology for agent oriented programming
Our goal in this paper is to introduce and motivate a methodology, called \emph{Tropos}, for building agent oriented software systems. Tropos is based on two key ideas. First, the notion of agent and all the related mentalistic notions (for instance: beliefs, goals, actions and plans) are used in all phases of software development, from the early analysis down to the actual implementation. Second, Tropos covers also the very early phases of requirements analysis, thus allowing for a deeper understanding of the environment where the software must operate, and of the kind of interactions that should occur between software and human agents. The methodology is illustrated with the help of a case study.
10751686
Experimenting with Linguistic Tools for Conceptual Modelling: Quality of the Models and Critical Features
This paper presents the results of three experiments designed to assess the extent to which a Natural-Language Processing (NLP) tool improves the quality of conceptual models, specifically object-oriented ones. Our main experimental hypothesis is that the quality of a domain class model is higher if its development is supported by a NLP system. The tool used for the experiment – named NL-OOPS – extracts classes and associations from a knowledge base realized by a deep semantic analysis of a sample text. In our experiments, we had groups working with and without the tool, and then compared and evaluated the final class models they produced. The results of the experiments give insights on the state of the art of NL-based Computer Aided Software Engineering (CASE) tools and allow identifying important guidelines to improve their performance, highlighting which of the linguistic tasks are more critical to effectively support conceptual modelling.
14679432
On Goal-based Variability Acquisition and Analysis
We introduce a variability-intensive approach to goal decomposition that is tailored to support requirements identification for highly customizable software. The approach is based on the semantic characterization of OR-decompositions of goals. We first show that each high-level goal can be associated with a set of concerns, in response to which, alternative refinements of the goal can be introduced. A text corpus relevant to the domain of discourse can be used to derive such variability concerns that are specific to the problem. In parallel, contextual facts that can vary while a goal is being fulfilled are modeled. Then, a high-variability goal model is constructed aiming at responding to the predefined variability concerns completely, while contextual factors are used to test whether it addresses all realistic background circumstances. We apply our approach in a study from the geriatric health care domain
14329219
Incorporating Goal Analysis in Database Design: A Case Study from Biological Data Management
We present a case study of a real-world industrial application which produced several versions of conceptual schema design for a biological database during its evolution. We apply the techniques of early requirements analysis to produce a goal model of the problem domain. We then show that by incorporating goal analysis in the design process we can account for the original schemas by tracing them back to stakeholder goals. Moreover, the goal-oriented analysis supports the systematic examination of the space of design alternatives, and better explains what the output of the design process (a conceptual schema) really means. Our results advocate the need for an extended design methodology for databases driven by stakeholder goals
3393049
Data Sharing in the Hyperion Peer Database System
This demo presents Hyperion, a prototype system that supports data sharing for a network of independent Peer Relational Database Management Systems (PDBMSs). The nodes of such a network are assumed to be autonomous PDBMSs that form acquaintances at run-time, and manage mapping tables to define value correspondences among different databases. They also use distributed Event-Condition-Action (ECA) rules to enable and coordinate data sharing. Peers perform local querying and update processing, and also propagate queries and updates to their acquainted peers. The demo illustrates the following key functionalities of Hyperion: (1) the use of (data level) mapping tables to infer new metadata as peers dynamically join the network, (2) the ability to answer queries using data in acquaintances, and (3) the ability to coordinate peers through update propagation.
9641490
Discovering the Semantics of Relational Tables Through Mappings
Many problems in Information and Data Management require a semantic account of a database schema. At its best, such an account consists of formulas expressing the relationship (mapping) between the schema and a formal conceptual model or ontology (CM) of the domain. In this paper we describe the underlying principles, algorithms, and a prototype tool that finds such semantic mappings from relational tables to ontologies, when given as input simple correspondences from columns of the tables to datatype properties of classes in an ontology. Although the algorithm presented is necessarily heuristic, we offer formal results showing that the answers returned by the tool are correct for relational schemas designed according to standard Entity-Relationship techniques. To evaluate its usefulness and effectiveness, we have applied the tool to a number of public domain schemas and ontologies. Our experience shows that significant effort is saved when using it to build semantic mappings from relational tables to ontologies.