Early PKI projects fell short in getting the critical mass of users subscribed because they were too expensive and to ambigious. Now, beyond the hype, there is a demand for improvement of security step by step rather than for big projects. Now, linking up existing PKI-islands, using S/MIME, introducing single sign-on and rising awareness are hot topics. Our vision, however, remains a globally a...

I systems (IDSs) form an important component of IT security architectures, but the low proportion of hackers in the user population severely limits the usefulness of IDSs. Thus, even when the IDS is good, an intrusion signal may not imply that the user is more likely to be a hacker than a normal user. Ignoring the low base rate for the proportion of hackers results in acting on every intrusion ...

Traditionally, IT security investment decisions are made in isolation. However, as firms that compete for customers in an industry are closely interlinked, a macro perspective is needed in analyzing the IT security spending decisions and this is a key contribution of the paper. We introduce the notions of directand cross-risk elasticity to describe the customer response to adverse IT security e...

Safety and security are different but closely related concepts. Security is especially relevant in domains like finance, and safety is especially relevant in domains like healthcare and aviation. We review some of the safety problems besetting healthcare IT systems, and we show that some problems are technically open to improvement. Given that there are almost-free technologies (e.g., as part r...

IT security professionals' effectiveness in an organization is influenced not only by how usable their security management tools are but also by how well the organization's security management model (SMM) fits. Finding the right SMM is critical but can be challenging — trade-offs are inherent to each approach but their implications aren't always clear. The authors present a case study of one ac...

Strong, machine-checked security proofs of operating systems have been in the too hard basket long enough. They will still be too hard for large mainstream operating systems, but even for systems designed from the ground up for security they have been counted as infeasible. There are high-level formal models, nice security properties, ways of architecting and engineering secure systems, but no ...

Information technology (IT) security certifications have proliferated in recent years. However they differ in regards to stakeholder considerations of credibility, accessibility and relevance. Key stakeholders with an interest in selecting an IT security certification (IT security professionals, employers, governments and higher education institutes) lack a systematic approach for differentiati...

The protection of safety-critical and infrastructure systems (such as automation systems for utilities, but also for manufacturing plants) against electronic and communication network based attacks becomes more and more important. This paper investigates how such safety-critical plants and automation systems can be secured against information system and network based attacks. The two common app...

As part of the research project"Secure information networks of small- and medium-sized energy providers"(SIDATE), a survey about the IT security status of German energy providers was conducted. The project itself is focused on the IT security of small- and medium-sized energy providers. In August 2016, 881 companies listed by the Federal Network Agency were approached. Between, September 1 st 2...

In the last years, automotive systems evolved to be more and more software-intensive systems. As a result, considerable attention has been paid to establish an efficient software development process of such systems, where reliability is an important criterion. Hence, model-driven development (MDD), software engineering and requirements engineering (amongst others) found their way into the syste...