A Distributed Calculus for Role-Based Access Control

Role-based access control (RBAC) is increasingly attracting attention because it reduces the complexity and cost of security administration by interposing the notion of role in the assignment of permissions to users. In this paper, we present a formal framework relying on an extension of the π calculus to study the behavior of concurrent systems in a RBAC scenario. We define a type system ensuring that the specified policy is respected during computations, and a bisimulation to equate systems. The theory is then applied to three meaningful examples, namely finding the ‘minimal’ policy to run a given system, refining a system to be run under a given policy (whenever possible), and minimizing the number of users in a given system without changing the overall behavior

Comparative Analysis of Business Object Approaches

This paper presents a comparison of several technologies for developing distributed applications. The specific technologies into consideration are: one focused on COM/DCOM/COM and Microsoft technologies, Internet Explorer and ActiveX - and the other focused on Netscape, CORBA, JAVA/J2EE solutions.integrated technologies, interoperability, distributed systems, components, distributed architecture

Supportive treatment in casework with the aged: a study of thirty cases in service for older people, Family Service Association of Greater Boston, from 1949 through 1953

Thesis (M.S.)--Boston Universit

The nature of IT services from a management and IS research point of view

Theory building is not only underdeveloped in IT services management research, but in general in IS. Given the paradigm shift that comes from the development away from a networked economy towards a network economy, the lack of spending enough attention to theorizing in IS becomes even more obvious. In the light of other "megatrends" in IS research, such as the increasing professionalization and use of statistical methods and the exploitation of extremely large sets of data (often harvested from social media sites), we might lose interest in theorizing in the presence of the tremendous amount of available empirical data. In this position paper, the author advocates that services science researchers should focus on rigor and relevance in their research approaches

Systematic case study research : a practice-oriented introduction to building an evidence base for counselling and psychotherapy

Background: Historically, clinical case studies have played a central role in counselling and psychotherapy training and practice, by allowing practitioners to learn about ideas and interventions being developed by colleagues. In recent years, the development of methods for systematic collection and analysis of case data has made it possible for case study research to begin to make a contribution to the evidence base for therapy policy and practice. Aim: This paper provides an overview of the characteristics of rigorous case study research, introduces a set of studies that exemplify these principles, and reviews the relevance of systematic case study inquiry for policy, practice and training. Conclusions: If case study research is to fulfil its potential as a source of research-based knowledge, it is essential for practitioners to publish more systematic case studies that document the range and scope of everyday therapeutic practice. It is also necessary to carry out further research into a variety of methodological issues associated with single-case inquiry, as a means of further developing this approach to practice-based research