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Internet of Things (IoT) deployments are becoming increasingly automated and vastly more complex. Facilitated by programming abstractions such as trigger-action rules, end-users can now easily create new functionalities by interconnecting their devices and other online services. However, when multiple rules are simultaneously enabled, complex system behaviors arise that are difficult to understand or diagnose. While history tells us that such conditions are ripe for exploitation, at present the security states of trigger-action IoT deployments are largely unknown. In this work, we conduct a comprehensive analysis of the interactions between trigger-action rules in order to identify their security risks. Using IFTTT as an exemplar platform, we first enumerate the space of inter-rule vulnerabilities that exist within trigger-action platforms. To aid users in the identification of these dangers, we go on to present iRuler, a system that performs Satisfiability Modulo Theories (SMT) solving and model checking to discover inter-rule vulnerabilities within IoT deployments. iRuler operates over an abstracted information flow model that represents the attack surface of an IoT deployment, but we discover in practice that such models are difficult to obtain given the closed nature of IoT platforms. To address this, we develop methods that assist in inferring trigger-action information flows based on Natural Language Processing. We develop a novel evaluative methodology for approximating plausible real-world IoT deployments based on the installation counts of 315,393 IFTTT applets, determining that 66% of the synthetic deployments in the IFTTT ecosystem exhibit the potential for inter-rule vulnerabilities. Combined, these efforts provide the insight into the real-world dangers of IoT deployment misconfigurations. 

The generation of a high‐frequency plasmaspheric hiss (HFPH) wave observed by Van Allen Probes is studied in this letter for the first time. The wave has a moderate power spectral density (∼10⁻⁶ nT²/Hz), with a frequency range extended from 2 to 10 kHz. The correlated observations of waves and particles indicate that HFPH is associated with the enhancement of electron flux during the substorm on 6 January 2014. Calculations of the wave linear growth rate driven by the fitted electron phase space density show that the electron distribution after the substorm onset is efficient for the HFPH generation. The energy of the contributing electrons is about 1–2 keV, which is consistent with the observation. These results support that the observed HFPH is likely to be generated locally inside the plasmasphere due to the instability of injected kiloelectron volt electrons.

 

Ag nanorods receive intensive attention due to the excellent plasmonic properties. However, the difficulty in synthesis of monodisperse Ag nanorods with broad aspect ratios has limited their in‐depth applications. Here, a seed‐mediated method is reported for the synthesis of Ag nanorods with lengths from 65 to 5000 nm, corresponding to aspect ratios from 2 to 156. The plasmonic resonance is tuned from visible to mid‐infrared wavelength. The synthesis protocol relies on robust Au seeds synthesized inN,N‐dimethylformamide (DMF), which induces the one‐dimensional (1D) growth of Ag atoms. To maintain symmetry breaking initiated by the Au seeds, the reduction rate of Ag⁺is decreased by adding hexadecyltrimethylammonium chloride (CTAC) to form AgCl particles. The optimized conditions to prevent the homogeneous nucleation of Ag nanoparticles and residue of AgCl particles in products are identified, under which the conversion efficiency of Ag ions to Ag nanorods is evaluated about 48%. More importantly, the anisotropic Ag nanorods are self‐assembled into monolayers at interfaces with the long axis of Ag nanorods perpendicular or parallel to the interfaces, respectively. The as‐fabricated monolayers exhibit uniform and reproducible surface‐enhanced Raman scattering (SERS) activities. The optimal SERS performance is achieved from Ag nanorod monolayer with vertical orientation and the longest rod length.