Based on the interconnection of currently about 45.000 Autonomous Systems (ASs) the Internet and its routing system in particular is highly fragile. To exchange inter-AS routing information, the Border Gateway Protocol (BGP) is used since the very beginning, and will be used for the next years, even with IPv6. BGP has many weaknesses by design, of which the implicit trust of ASs to each other AS is the most threatening one. Although this has been topic on network security research for more than a decade, the problem still persists with no solution in sight. This paper contributes a solution to stay up to date concerning inter-AS routing anomalies based on a broad evidence collected from different publicly available sources. Such an overview is necessary to question and to rely on the Internet as a basis in general and must be a part of every cyber defense strategy. Existing methods of detecting inter-AS routing anomalies result in large sets of real time routing anomalies, based on the evaluation of routing announcements collected from different viewpoints. To decide, whether a detected anomaly is harmful or not, each of them has to be classified and correlated to others. We combine various detection methods and improve them with additional publicly available information. The improved outcome of the implemented routing anomaly detection system is used as input for our classification algorithms

Thermal radiation of gadsolid mixtures in high-temperature heat exchangers is of considerable importance for the design of heat exchange surfaces. Therefore, an experimental plant was constructed to measure solid particle emissivities, since there is a lack of relevant data in the existing literature. A theoretical equation was derived to describe the solid particle emissivity as a function of layer thickness, specific solid surface area, solid loading and absorption and scatter coefficients. Measurements were carried out for fluidized bed ash and quartz sand. The emissivities of these particle fractions increase with increasing layer thickness, solid loading, specific solid surface area and temperature. The description of these data by the derived model equation is very satisfactory. No dependence on wavelength was observed. The ash components do exert some influence which, for the present, cannot be described exactly.

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