Reactive Security for SDN/NFV-enabled Industrial Networks leveraging Service Function Chaining

The innovative application of 5G core technologies, namely Software Defined Networking (SDN) and Network Function Virtualization (NFV), can help reduce capital and operational expenditures in industrial networks. Nevertheless, SDN expands the attack surface of the communication infrastructure, thus necessitating the introduction of additional security mechanisms. These major changes could not leave the industrial environment unaffected, with smart industrial deployments gradually becoming a reality; a trend that is often referred to as the 4th industrial revolution or Industry 4.0. A wind park is a good example of an industrial application relying on a network with strict performance, security, and reliability requirements, and was chosen as a representative example of industrial systems. This work highlights the benefit of leveraging the flexibility of SDN/NFV-enabled networks to deploy enhanced, reactive security mechanisms for the protection of the industrial network, via the use of Service Function Chaining. Moreover, the implementation of a proof-of-concept reactive security framework for an industrial-grade wind park network is presented, along with a performance evaluation of the proposed approach. The framework is equipped with SDN and Supervisory Control and Data Acquisition (SCADA) honeypots, modelled on and deployable to the wind park, allowing continuous monitoring of the industrial network and detailed analysis of potential attacks, thus isolating attackers and enabling the assessment of their level of sophistication. Moreover, the applicability of the proposed solutions is assessed in the context of the specific industrial application, based on the analysis of the network characteristics and requirements of an actual, operating wind park

Event-based Customization of Multi-tenant SaaS Using Microservices

Popular enterprise software such as ERP, CRM is now being made available on the Cloud in the multi-tenant Software as a Service (SaaS) model. The added values come from the ability of vendors to enable customer-specific business advantage for every different tenant who uses the same main enterprise software product. Software vendors need novel customization solutions for Cloud-based multi-tenant SaaS. In this paper, we present an event-based approach in a non-intrusive customization framework that can enable customization for multi-tenant SaaS and address the problem of too many API calls to the main software product. The experimental results on Microsoft’s eShopOnContainers show that our approach can empower an event bus with the ability to customize the flow of processing events, and integrate with tenant-specific microservices for customization. We have shown how our approach makes sure of tenant-isolation, which is crucial in practice for SaaS vendors. This direction can also reduce the number of API calls to the main software product, even when every tenant has different customization services.publishedVersio

What Does the n-Back Task Measure as We Get Older? Relations Between Working-Memory Measures and Other Cognitive Functions Across the Lifespan

Working memory (WM) declines with increasing age. The WM capacity is often measured by means of the computerized version of the n-back task. Although the n-back task is widely used in aging research, little is known about its construct validity and specific cognitive functions involved in this task. Moreover, to date, no studies analyzed the construct validity as a function of age. To this end, we conducted a study in a sample of N = 533 individuals aged between 20 and 80 years. The sample was divided into three age groups: young (20–40), middle-aged (41–60), and old (61–80 years). A number of psychometric tests was selected that measure attention, memory, and executive control to elucidate the impact of these constructs on n-back performance. A series of correlation analyses was conducted to assess the relationship between n-back performance and specific cognitive functions in each age group separately. The results show a progressive increase in reaction times and a decrease in the proportion of detected targets from young to old subjects. Age-related impairments were also found in all psychometric tests except for the vocabulary choice test measuring crystallized intelligence. Most importantly, correlations yielded different age-related patterns of functions contributing to performance in the n-back task: whereas performance was most related to executive functions in young age, a combination of attentional and executive processes was associated with performance in middle-aged subjects. In contrast, in older age, mainly attentional, verbal memory, and updating and to a lesser extent executive processes seem to play a crucial role in the n-back task, suggesting a shift of processing strategies across the lifespan

The psychological investigation of subjective time : new concepts and contemporary research methods

In contrast to physical (objective) time, the subjective representation or perception of time is influenced by various factors. For example, in everyday life, humans perceive time to pass slower or faster depending on the situational context, and this impression may lead to an over- or underestimation of duration. Based on five sub-projects, the present work investi-gates several different phenomena in the field of subjective time. The first two sub-projects (meta-analytical reviews) focused on time perception in clinical populations. The results indicate that time passes less quickly for depressive patients. Judgments of duration, however, do not differ between patients and healthy control subjects. Patients with schizophrenia show a strong increase in the variability of their duration judgments, whereas mean duration esti-mates do not differ between patients and controls. In sub-projects three and five, I investi-gated whether subjective time can by influenced by (subtle) interpersonal cues. The results indicate rather weak effects of gaze direction on duration judgments and the spatialized representation of time (mental time lines). Sub-project four comprised two experiments on the effects of chronometric counting on the production of time intervals. Interestingly, while productions became less variable (more precise), the accuracy of time productions did not benefit from counting. Beyond the specific foci of the different sub-projects, the results from the present work approach some fundamental aspects of subjective time. Based on the meta-analytical review of time perception in depressive patients, factors that influence the subjec-tive passage of time do not necessarily affect the perception of duration. Therefore, passage and duration need to be conceptualized as disentangled temporal dimensions. The concept of passing time may be more closely related to the concept of a mental time than to the concept of duration. The meta-analytical review on time perception in patients with schizophrenia and the experiments on the effects of counting on time productions show that measures of accuracy and measures of precision reflect independent aspects of subjective time, which need to be considered carefully in models of time perception and by future research.Im Gegensatz zur physikalischen (objektiven) Zeit ist unsere subjektive Repräsentation oder Wahrnehmung von Zeit von zahlreichen Einflussgrößen abhängig. Beispielsweise haben Menschen den Eindruck, die Zeit fließe je nach situativem Kontext schneller oder langsamer und dieser Eindruck könnte zu systematischen Über- oder Unterschätzungen von Zeitdauern führen. Im Rahmen von fünf Teilprojekten untersucht die vorliegende Arbeit verschiedene Phänomene aus dem Forschungsbereich der subjektiven Zeit. Die ersten beiden Teilprojekte (metaanalytische Übersichtsarbeiten) widmen sich dabei der Zeitwahrnehmung in klinischen Populationen. Die Ergebnisse zeigen, dass Zeit für depressive Patienten langsamer zu vergehen scheint. Die Beurteilung von Zeitdauern unterscheidet sich hingegen nicht systemisch zwischen Patienten mit einer Depression und psychisch gesunden Kontrollprobanden. Schizophreniepatienten weisen eine starke Zunahme in der Variabilität ihrer Dauereinschätzungen auf. Im Mittel unterscheiden sich ihre Dauerbeurteilungen jedoch nicht von denen gesunder Kontrollpersonen (keine systematischen Über- oder Unterschätzungen). In den Teilprojekten drei und fünf habe ich mich mit der Fragestellung befasst, ob subjektive Zeit durch (subtile) interpersonale Hinweisreize beeinflusst werden kann. Die Ergebnisse legen schwache Effekte von Blickorientierung auf die Beurteilung von Dauer und die verräumlichte mentale Repräsentation von Zeit (mentale Zeitlinien) nahe. Teilprojekt vier umfasst zwei Experimente zu den Effekten von chronometrischem Zählen auf die Produktion von Zeitintervallen. Interessanterweise führte Zählen zwar zu weniger variablen (also präziseren) Dauerproduktionen, während sich die Genauigkeit der Produktionen (Nähe der Produktion zur tatsächlichen Dauer des Intervalls; Akkuratheit) jedoch nicht verbessert. Jenseits der spezifischen Fragestellungen der einzelnen Teilprojekte haben die Ergebnisse der vorliegenden Arbeit auch Implikationen bezüglich einiger fundamentaler Aspekte subjektiver Zeit. Auf Basis der Metaanalyse zur Zeitwahrnehmung bei depressiven Patienten ist festzustellen, dass bestimmte Faktoren, die die subjektive Geschwindigkeit des Fließens der Zeit beeinflussen, nicht notwendigerweise auch die Beurteilung (Repräsentation) von Dauer beeinflussen. Dementsprechend sollten Zeitfluss und Dauer als unterschiedliche Dimensionen subjektiver Zeit betrachtet werden. Das Konzept eines Zeitflusses ist möglicherweise stärker verknüpft mit der verräumlichten Repräsentation von Zeit als mit dem Konzept von Dauer. Die Metaanalyse zur Zeitwahrnehmung bei Patienten mit Schizophrenie sowie die Experimente zu den Effekten von Zählen auf die Produktion von Zeitintervallen zeigen, dass Maße der Genauigkeit (Akkuratheit) und Maße der Variabilität (Präzision) unabhängige Aspekte subjektiver Zeit abbilden. Modelle der Zeitwahrnehmung und zukünftige Forschung sollten diese Maße mit entsprechender Aufmerksamkeit voneinander dissoziieren