Physical Simulation of Inarticulate Robots

In this note we study the structure and the behavior of inarticulate robots. We introduce a robot that moves by successive revolvings. The robot's structure is analyzed, simulated and discussed in detail

Information Security Theory and Practice: Securing the Internet of Things: 8th IFIP WG 11.2 InternationalWorkshop, WISTP 2014, Heraklion, Crete, Greece, June 30-July 2, 2014

International audienceBook Front Matter of LNCS 850

Operand Folding Hardware Multipliers

This paper describes a new accumulate-and-add multiplication algorithm. The method partitions one of the operands and re-combines the results of computations done with each of the partitions. The resulting design turns-out to be both compact and fast. When the operands' bit-length $m$ is 1024, the new algorithm requires only $0.194m+56$ additions (on average), this is about half the number of additions required by the classical accumulate-and-add multiplication algorithm ($\frac{m}2$)

The Balkans Continued Fraction

In a previous article we gave a collection of continued fractions involving Catalan's constant. This paper provides more general formulae governing those continued fractions. Having distinguished different cases associated to regions in the plan, we nickname those continued fractions \enquote{The Balkans} as they divide into areas which are related but still different in nature. Because we do not provide formal proofs of those machine-constructed formulae we do not claim them to be theorems. Still, each and every proposed formula was extensively tested numerically

Divisibility, Smoothness and Cryptographic Applications

This paper deals with products of moderate-size primes, familiarly known as smooth numbers. Smooth numbers play a crucial role in information theory, signal processing and cryptography. We present various properties of smooth numbers relating to their enumeration, distribution and occurrence in various integer sequences. We then turn our attention to cryptographic applications in which smooth numbers play a pivotal role

The Polynomial Composition Problem in (Z/nZ)[X]

Abstract. Let n be an RSA modulus and let P, Q ∈ (Z/nZ)[X]. This paper explores the following problem: Given polynomials Q and Q(P), find polynomial P. We shed light on the connections between the above problem and the RSA problem and derive from it new zero-knowledge protocols suited to smart-card applications. Keywords: Polynomial composition, zero-knowledge protocols, Fiat-Shamir protocol, Guillou-Quisquater protocol, smart cards

Robust Encryption, Extended

Robustness is a notion often tacitly assumed while working with encrypted data. Roughly speaking, it states that a ciphertext cannot be decrypted under different keys. Initially formalized in a public-key context, it has been further extended to key-encapsulation mechanisms, and more recently to pseudorandom functions, message authentication codes and authenticated encryption. In this work, we motivate the importance of establishing similar guarantees for functional encryption schemes, even under adversarially generated keys. Our main security notion is intended to capture the scenario where a ciphertext obtained under a master key (corresponding to Authority 1) is decrypted by functional keys issued under a different master key (Authority 2). Furthermore, we show there exist simple functional encryption schemes where robustness under adversarial key-generation is not achieved. As a secondary and independent result, we formalize robustness for digital signatures – a signature should not verify under multiple keys – and point out that certain signature schemes are not robust when the keys are adversarially generated. We present simple, generic transforms that turn a scheme into a robust one, while maintaining the original scheme’s security. For the case of public-key functional encryption, we look into ciphertext anonymity and provide a transform achieving it