Jiska Classen

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Wireless networks based on visible light communication (VLC) are often considered to be resilient to eavesdropping by design, since light cannot penetrate most walls and objects. In this paper, we experimentally study the ability of a VLC eavesdropper to intercept and decode a transmission even while being outside of the direct beam. We design a testbed(More)
Wireless covert channels promise to exfiltrate information with high bandwidth by circumventing traditional access control mechanisms. Ideally, they are only accessible by the intended recipient and-for regular system users/operators-indistinguishable from normal operation. While a number of theoretical and simulation studies exist in literature, the(More)
Cellular ATP levels are determined by the rates of ATP production and ATP hydrolysis. Both phenomena are affected by ischemia. Mitochondrial enzymes are damaged, inhibiting this organelle's ability to make ATP. Mitochondria are also uncoupled by ischemia and have the ability to hydrolyze ATP. We designed a series of experiments to determine whether(More)
Johannes Braun a,∗, Florian Volk b, Jiska Classen c, Johannes Buchmann a and Max Mühlhäuser b a Theoretical Computer Science, Cryptography and Computer Algebra, Technische Universität Darmstadt, Darmstadt, Germany E-mails: {jbraun, buchmann}@cdc.informatik.tu-darmstadt.de b Telecooperation Lab, Technische Universität Darmstadt and CASED, Darmstadt, Germany(More)
Next generation wireless networks utilizing millimeter waves (mm-waves) achieve extremely high data rates using narrow signal beams. Featuring a high directivity and being susceptible to blockage by objects, mm-waves are often assumed to be hard to intercept. However, small-scale objects within the beam cause reflections, thus enabling eavesdroppers to(More)
Securing visible light communication (VLC) systems on the physical layer promises to prevent against a variety of attacks. Recent work shows that the adaption of existing legacy radio wave physical layer security (PLS) mechanisms is possible with minor changes. Yet, many adaptations open new vulnerabilities due to distinct propagation characteristics of(More)
Current mm-wave indoor propagation analysis techniques have limited options when it comes to more than one transmitter and receiver. Experimental testbed hardware is expensive and state-of-the-art simulation methods, such as statistical channel models, are limited to specific scenarios. To overcome these problems, we present mmTrace, a fast deterministic(More)
While radio-based indoor localization schemes achieve decimeter-scale accuracy, they typically require precise reference measurements, multiple infrastructure nodes, or a multi-RF-chain anchor. In this paper, we propose Pseudo LATeration (PLAT), an indoor localization protocol that requires only a single RF chain infrastructure anchor and does not require(More)
The advantages of mm-wave communication technology with highly directional transmissions enable high data rates in dense wireless networks. Even though first consumer hardware is already available, specific propagation effects are not yet well understood. Analyses of wireless network behavior with mm-wave communication links are required to design efficient(More)
Tens of millions of wearable fitness trackers are shipped yearly to consumers who routinely collect information about their exercising patterns. Smartphones push this health-related data to vendors’ cloud platforms, enabling users to analyze summary statistics on-line and adjust their habits. Third-parties including health insurance providers now offer(More)