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Discovering Connected Objects in the Criminal Investigations

More and more things around us are becoming digital and connected to the Internet. This market ranges from smart devices, wellness and health control to smart cities. This development offers to malicious parties the possibility of carrying out attacks, directly impacting the consumers of these new services. Thus, the connected objects are actors or witnesses of events that have occurred. This opens up a challenge for security and forensic investigations on the Internet of Things (IoT).In this article, we present the problem of finding connected objects on an offence scene. In the absence of a technical solution, the investigators limit themselves to a manual search. Hidden objects are often neither detected nor found. Thus, we aim to give a clear and precise image of the current devices. We also want to determine their position.This work focuses on the study of the digital signature of the scene and the radio frequency characteristics of the objects. To understand the electromagnetic environment, we use a software defined radio (SDR) and we develop several tools: a sensor for a single protocol and a mesh network of sensors. The SDR returns the used frequencies. The single receiver offers a global mapping of the environment on a given protocol. The multi-sensor mesh network gives a precise and targeted vision of the infrastructure connected to several protocols and frequencies. We propose to assess the relevance of the measurement methods in relation to operational needs, on the basis of a use case and feedbacks.