Conceptual experiment of geolocationaware IoT data dissemination model IoT devices are increasingly distributed around the world and have been digitizing physical things so far. However, a current IoT service is designed to be independent; it is not intended to conduct data collaboration with other IoT services. It must be important to be able to commonly use IoT data even from IoT devices managed for different services. To promote IoT data collaboration, we proposed a crossdomain data fusion platform on the basis of geographical proximity, called geocentric information platform (GCIP). Although GCIP enabled to collect and process data generated associated with geolocation of data generation, how to disseminate them should be still discussed. We can easily assume that some data summarization is preferable when data are used far away from the location of data generation. We also assume that there must be privacy and security issues in IoT data. That is why we propose a geolocationaware IoT data dissemination model, which summarizes data due to the different distance between the location of the data source and the location of the destination. That is, as the distance becomes longer, the data is coarser. In this paper, we particularly focus on the behavior of the model and show the conceptual behavior by conducting experiments in a real environment.

Communication Aspects of the Integration of Wireless IoT Devices with Distributed Ledger Technology The pervasive need to safely share and store information between devices calls for the replacement of centralized trust architectures with decentralized ones. DLTs are seen as the most promising enabler of decentralized trust, but they still lack technological maturity, and their successful adoption depends on the understanding of the fundamental design tradeoffs and their reflection in the actual technical design. This work focuses on the challenges and potential solutions for an effective integration of DLTs in the context of the Internet of Things (IoT). We first introduce the landscape of IoT applications and discuss the limitations and opportunities offered by DLTs. Then we review the technical challenges encountered in the integration of resourceconstrained devices with distributed trust networks. We describe the common traits of lightweight synchronization protocols, and propose a novel classification rooted in the IoT perspective. We identify the need for receiving ledger information at the endpoint devices, implying a twoway data exchange that contrasts with the conventional uplinkoriented communication technologies intended for IoT systems.