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VTDL: A Notation for Data Stream Processing Applications

The continuing growth of the Internet of Things (IoT) requires established stream processing engines (SPEs) to cope with new challenges, like the geographic distribution of IoT sensors and clouds hosting the SPEs. These challenges obligate SPEs to support distributed stream processing across different geographic locations which also require a new approach on how data stream processing topologies are defined. In this paper, we identify required features for next-generation SPEs and introduce the Vienna Topology Description Language (VTDL). This language is specifically designed to address challenges for next-generation SPEs and proposes several novel aspects compared to existing topology description concepts. To assess not only the feasibility but also the reduced management overhead due to the VTDL, we evaluate the VTDL within the VISP stream processing ecosystem and show that the usage of the VTDL approach results in a management time reduction of up to 18 times.