Service brokerage with Prolog

Service brokerage is a complex problem. At the design stage the semantic gap between user, device and system requirements must be bridged, and at the operational stage the conflicting objectives of many parties in the value chain must be reconciled. For example why should a user who wants to watch a film need to understand that due to limited battery power the film can only be shown in low resolution? Why should the user have to understand the business model of a content provider? To solve these problems we present (1) the concept of a packager who acts as a service broker, (2) a design derived systematically from a semi-formal specification (the CC-model), and (3) an implementation using our Prolog based LicenseScript language

Goedereede, Ouddorp

Veldtekeningen van de opgravingen uitgevoerd door J.A. Trimpe Burger in 1959/1960 en 1982/1983 te Ouddorp op Goeree-Overflakkee. Aangetroffen zijn resten van een nederzetting uit de Romeinse tijd

Security for ICT collaboration tools

In order for collaboration tools to be productive in an operational setting, an information base that is shared across the collaborating parties is needed. Therefore, a lot of research is done for tooling to create such a common information base in a collaboration tool. However, security is often not given a lot of attention. In this paper we argue that security is a necessary part of collaboration tooling. We identified and categorized security issues in a collaboration tool MiReCol and recognized a new group of security issues that apply to collaboration tooling in general. Those new issues are related to the fact that several different authorized users are using the collaboration tool together. In those situations the threat exists that an unauthorized user can view confidential data.We conclude that security is a necessary part of an ICT collaboration tool and depending on the case security countermeasures have to be implemented. Most security issues can be handled with existing techniques. However to protect confidentiality in a multi-user environment extra techniques have to be developed. © 2010 IADIS

Two worlds, one smart card : An integrated solution for physical access and logical security using PKI on a single smart card

We present a use case of the introduction of a large scale Public Key Infrastructure (PKI) environment in an incumbent telecommunications company in The Netherlands. The main characteristics of the case are the integration of an existing physical access facility with a PKI environment for logical security of the company ICT infrastructure. In fact, both are accessed using a single (smart) company card. The purpose was to implement a high level of security, within the practical constraints at hand, and to reach a level of reduced sign-on for company employees. This integration poses numerous challenges. In this article we describe how PKI is actually introduced to support authentication, signing and encryption services for its employees. 18.000 personalised smart cards with PKI were issued, controlling access to over 1500 buildings, fitted with in total more than 6000 smart card readers. The smart cards also controlled access to 14.000 personal workstations both desktops and laptops (each fitted with a contact smart card reader), with access to over a 1000 different applications