Formal Computational Unlinkability Proofs of RFID Protocols

We set up a framework for the formal proofs of RFID protocols in the computational model. We rely on the so-called computationally complete symbolic attacker model. Our contributions are: i) To design (and prove sound) axioms reflecting the properties of hash functions (Collision-Resistance, PRF); ii) To formalize computational unlinkability in the model; iii) To illustrate the method, providing the first formal proofs of unlinkability of RFID protocols, in the computational model

Direct measurement of salt–mineral repulsion using atomic force microscopy

The disjoining pressure between a mineral and soluble salt crystal in concentrated aqueous solution has been successfully measured with atomic force microscopy

Physical properties of grafted polymer monolayers studied by scanning force microscopy:Morphology, friction, elasticity

Monolagen van polymeren die met één uiteinde aan een oppervlak verankerd zijn aan een oppervlak spelen een belangrijke rol in de stabilisatie van colloiden, chromatografie, adhesie, bevochtiging van oppervlakken, microelectronica en biocompatibiliteit van kunstmatige organen. Het doel van dit proefschrift is de studie van de morfologie, frictie en de elasticiteit van deze monolagen op nanoscopische Scanning Probe Microscopen (SP-M's) hebben een revolutie teweeggebracht in de de microscopie aan oppervlakken. ... Zie: Samenvatting

The 5G-AKA Authentication Protocol Privacy

We study the 5G-AKA authentication protocol described in the 5G mobile communication standards. This version of AKA tries to achieve a better privacy than the 3G and 4G versions through the use of asymmetric randomized encryption. Nonetheless, we show that except for the IMSI-catcher attack, all known attacks against 5G-AKA privacy still apply. Next, we modify the 5G-AKA protocol to prevent these attacks, while satisfying the cost and efficiency constraints of the 5G-AKA protocol. We then formally prove that our protocol is sigma-unlinkable. This is a new security notion, which allows for a fine-grained quantification of a protocol privacy. Our security proof is carried out in the Bana-Comon indistinguishability logic. We also prove mutual authentication as a secondary result.Comment: Changes: - added details when describing some attacks. - added a constant message in the AKA+ protoco

Atomic Force Microscopy and Real Atomic Resolution. Simple Computer Simulations.

Using a simple computer simulation for AFM imaging in the contact mode, pictures with true and false atomic resolution are demonstrated. The surface probed consists of two f.c.c. (111) planes and an atomic vacancy is introduced in the upper layer. Changing the size of the effective tip and its registry with respect to the atoms of the crystal probed, images with completely different qualitative features are obtained. If the effective tip is a single atom the vacancy is clearly imaged. However, if the tip consists of several atoms and is in registry with the sample, a virtual atom appears instead of the vacancy and the crystal lattice is perfectly reproduced. If the tip is out of registry with respect to the sample, artifacts having the size of the effective tip are reported.