In B2B contract enactment, cooperation should be taken into account when modeling contractual commitments through obligations. We advocate a directed deadline obligation approach, taking inspiration on international legislation over trade procedures. Our proposal is based on authorizations granted in specific states of an obligation lifecycle model. Flexible deadlines provide an additional leve...

Many organizations struggle with ineffective and/or inefficient access control, but these problems and their consequences often remain invisible to security decision-makers. Prior research has focused on improving the policy-authoring part of authorization and does not consider the full range of underlying problems, and their impact on organizations. We present a study of 118 individuals’ exper...

Traditional security systems are not easily scalable and can become single points of failure or performance bottlenecks when used on a large-scale distributed system such as the Internet. This problem occurs also when using a Public Key Infrastructure (PKI) with a hierarchical trust model. SDSI/SPKI is a PKI that adopts a more scalable trust paradigm, which is focused on the client and based on...

Today, most Internet applications are based on the client-server model. In this model, typically, the server distrusts clients, and grants each client access rights according to the client’s identity. This enables the server to record a lot of personal information about clients: identity, usual IP address, postal address, credit card number, purchase habits, etc. Such a model is thus necessaril...

Requirements for access control in CSCW systems have often been stated but groupware in use today does not meet most of these requirements There are prac tical reasons for this but one of the problems is the inherent complexity of sophis ticated access control models We propose a general authorization model that emphasizes conceptual simplicity Several extensions to the basic model address well...

In recent years, workkow management systems (WFMSs) have gained popularity both in research as well as in commercial sectors. WFMSs are used to coordinate and streamline business processes of an organization. Often, very large WFMSs are used in organizations with users in the range of several thousands and number of process instances in the range of tens of thousands. To simplify the complexity...