The Internet of Things (IoT) represents one of the fastest emerging trends in the area of information and communication technology. The main challenge in the IoT is the timely gathering of data streams from potentially millions of sensors. In particular, those sensors are widely distributed, constantly in transit, highly heterogeneous, and unreliable. To gather data in such a dynamic environment efficiently, two techniques have emerged over the last decade: adaptive sampling and adaptive filtering. These techniques dynamically reconfigure rates and filter thresholds to trade-off data quality against resource utilization. In this paper, we survey representative, state-of-the-art algorithms to address scalability challenges in real-time and distributed sensor systems. To this end, we cover publications from top peerreviewed venues for a period larger than 12 years. For each algorithm, we point out advantages, disadvantages, assumptions, and limitations. Furthermore, we outline current research challenges, future research directions, and aim to support readers in their decision process when designing extremely distributed sensor systems.

The Internet of Things (IoT) presents a novel computing architecture for data management: a distributed, highly dynamic, and heterogeneous environment of massive scale. Applications for the IoT introduce new challenges for integrating the concepts of fog and cloud computing as well as sensor networks in one unified environment. In this paper, we present early approaches that address parts of the overall problem space. All approaches are incorporated into NebulaStream (NES), our novel data processing platform that addresses the heterogeneity, unreliability, and scalability challenges of the IoT and thus provides efficient data management for future applications.

Fog computing was designed to support the specific needs of latency-critical applications such as augmented reality, and IoT applications which produce massive volumes of data that are impractical to send to faraway cloud data centers for analysis. However this also created new opportunities for a wider range of applications which in turn impose their own requirements on future fog computing platforms. This article presents a study of a representative set of 30 fog computing applications and the requirements that a general-purpose fog computing platform should support.