98 research outputs found
Dynamic Security-aware Routing for Zone-based data Protection in Multi-Processor System-on-Chips
In this work, we propose a NoC which enforces the
encapsulation of sensitive traffic inside the asymmetrical security
zones while using minimal and non-minimal paths. The NoC
routes guarantee that the sensitive traffic is communicated only
through the trusted nodes which belong to the security zone.
As the shape of the zones may change during operation, the
sensitive traffic must be routed through low-risk paths. We test
our proposal and we show that our solution can be an efficient
and scalable alternative for enforce the data protection inside the
MPSoC
Self-induced decoherence in dense neutrino gases
Dense neutrino gases exhibit collective oscillations where "self-maintained
coherence" is a characteristic feature, i.e., neutrinos of different energies
oscillate with the same frequency. In a non-isotropic gas, however, the flux
term of the neutrino-neutrino interaction has the opposite effect of causing
kinematical decoherence of neutrinos propagating in different directions, an
effect that is at the origin of the "multi-angle behavior" of neutrinos
streaming off a supernova core. We cast the equations of motion in a form where
the role of the flux term is manifest. We study in detail the symmetric case of
equal neutrino and antineutrino densities where the evolution consists of
collective pair conversions ("bipolar oscillations"). A gas of this sort is
unstable in that an infinitesimal anisotropy is enough to trigger a run-away
towards flavor equipartition. The "self-maintained coherence" of a perfectly
isotropic gas gives way to "self-induced decoherence."Comment: Revtex, 16 pages, 12 figure
Supernova Neutrino Opacity from Nucleon-Nucleon Bremsstrahlung and Related Processes
Elastic scattering on nucleons, \nu N -> N \nu, is the dominant supernova
(SN) opacity source for \mu and \tau neutrinos. The dominant energy- and
number-changing processes were thought to be \nu e^- -> e^- \nu and \nu\bar \nu
e^+ e^- until Suzuki (1993) showed that the bremsstrahlung process \nu\bar
\nu NN NN was actually more important. We find that for energy exchange,
the related ``inelastic scattering process'' \nu NN NN \nu is even more
effective by about a factor of 10. A simple estimate implies that the \nu_\mu
and \nu_\tau spectra emitted during the Kelvin-Helmholtz cooling phase are much
closer to that of \nu\bar_e than had been thought previously. To facilitate a
numerical study of the spectra formation we derive a scattering kernel which
governs both bremsstrahlung and inelastic scattering and give an analytic
approximation formula. We consider only neutron-neutron interactions, we use a
one-pion exchange potential in Born approximation, nonrelativistic neutrons,
and the long-wavelength limit, simplifications which appear justified for the
surface layers of a SN core. We include the pion mass in the potential and we
allow for an arbitrary degree of neutron degeneracy. Our treatment does not
include the neutron-proton process and does not include nucleon-nucleon
correlations. Our perturbative approach applies only to the SN surface layers,
i.e. to densities below about 10^{14} g cm^{-3}.Comment: 36 pages, LaTeX, 6 postscript figs included, matches version accepted
for publication in Astrophysical Journa
A Secure Dual-MCU Architecture for Robust Communication of IIoT Devices
The Industrial Internet of Things (IIoT) has already become a part of our
everyday life be it water supply, smart grid, or production, IIoT is
everywhere. For example, factory operators want to know the current state of
the production line. These new demands for data acquisition in modern plants
require industrial components to be able to communicate. Nowadays, network
communication in Industrial Control Systems (ICSs) is often implemented via an
IP-based protocol. This intercommunication also brings a larger attack surface
for hackers. If an IIoT device is influenced by attackers, the physical process
could be affected. For example, a high network load could cause a high Central
Processing Unit (CPU) load and influence the reaction time on the physical
control side. In this paper, we introduce a dual Microcontroller Unit (MCU)
setup to ensure a resilient controlling for IIoT devices like Programmable
Logic Controllers (PLCs). We introduce a possible solution for the demand of
secure architectures in the IIoT. Moreover, we provide a Proof of Concept (PoC)
implementation with a benchmark and a comparison with a standard PLC
Defeating microprobing attacks using a resource efficient detection circuit
Microprobing is an attack technique against integrated circuits implementing security functions, such as OTP tokens or smartcards. It allows intercepting secrets from onchip wires as well as injecting faults for other attacks. While the necessity to etch open chip packages and to remove the passivation layer makes microprobing appear expensive, it was shown that a successful attack can be run with equipment worth a few thousand euros. On the protector’s side, however, appropriate countermeasures such as active shields, redundancy of core components, or analog detection circuits containing large capacitors, are still expensive. We present a resource efficient microbing detection circuit that we call Low Area Probing Detector (LAPD). It measures minimal timing differences between on-chip wires caused by the capacitive load of microprobes. Simulations show that it can detect up-todate probes with capacitances as low as 10 fF. As a novelty, the LAPD is merely based on digital components and does not require analog circuitry, which reduces the required area and process steps compared to previous approaches.Postprint (author’s final draft
TOFU - Toggle Count Analysis made simple
Protection against physical attacks is a major requirement for cryptographic implementations running on devices which are accessible to an attacker. Side-channel attacks are the most common types of physical attacks, the most frequent side-channel is the device\u27s power consumption. In this work we propose a novel open-source tool called TOFU which synthesizes VCD simulation traces into power traces, with adjustable leakage models. Additionally, we propose a workflow which is only based on open-source tools. The functionality of TOFU and the proposed workflow was verified by a CPA of a AES hardware implementation. We also provide numbers for the required running time of TOFU for a trace synthesis with respect to the according VCD file size. Furthermore, we provide TOFU\u27s source code
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