In this paper we pick up an old challenge to design public key or white-box constructions from symmetric cipher components. We design several encryption schemes based on the ASASA structure ranging from fast and generic symmetric ciphers to compact public key and white-box constructions based on generic affine transformations combined with specially designed low degree non-linear layers. While ...

We present two new schemes that, in the absence of a centralized support, allow a pair of nodes of a mobile ad hoc network to compute a shared key without communicating. Such a service is important to secure routing protocols [1–3]. The schemes are built using the well-known technique of threshold secret sharing and are secure against a collusion of up to a certain number of nodes. We evaluate ...

The heterogeneity and relative limited resources of the nodes deployed in hierarchical wireless sensor network (WSN) impose a new strategy to guarantee security and confidentiality. A deployment strategy is proposed and focuses on two different levels: complexity of the scheme and security requirement for the application. Three different cryptography mechanisms may be concurrently used in the s...

In [10], we introduce a process calculus for describing security protocols and we propose a static and compositional analysis of entity authentication. In this paper we apply such a technique on well-known shared key authentication protocols. The analysis helps clarifying the protocol logics, suggests simplifications and reveals some attacks. Moreover we discuss how our analysis scales up to mu...

EPOC-2 is an asymmetric (public-key) hybrid encryption scheme based on the asymmetric cryptosystem of Okamoto and Uchiyama, [13], and the hybrid encryption scheme of Fujisaki and Okamoto, [5]. In simple terms it generates a random key for use with a symmetric cipher and enciphers the message using that symmetric cipher. It then enciphers the key, along with a check value, using the Okamoto-Uchi...

We define a framework to reason about sound implemen-tations of equational theories in the presence of an adap-tive adversary. In particular, we focus on soundess of staticequivalence. We illustrate our framework on several equa-tional theories: symmetric encryption, XOR, modular expo-nentiation and also joint theories of encryption and modu-lar exponentiation as well as...

This paper presents a cost-effective private-key cryptosystem for color images. The scheme allows for secret sharing of the color image by generating two color shares with dimensions identical to those of the original. Encryption is performed via simple binary operations realized at the image bit-levels altering both the spectral correlation among the RGB color components and the spatial correl...

We construct a language extension for process calculi for modelling the exchange of cryptographically composed data. More specifically, we devise a succinct syntax for terms and patterns that captures the intention behind perfect cryptography. The proposed language extension is independent of the choice of process calculus and is applicable to any calculus that supports exchange of data. Initia...

Key management play a central role for protecting communication in WSNs. Due to the limited memory resources and energy constraints, complex security algorithms cannot be used in sensor networks. Therefore, to secure data communication and well balance between the security level and the associated energy consumption is a challenging task. In this paper, we present an Improved Key management Sch...

Aggregate statistics computed from time-series data contributed by individual mobile nodes can be very useful for many mobile sensing applications. Since the data from individual node may be privacy-sensitive, the aggregator should only learn the desired statistics without compromising the privacy of each node. To provide strong privacy guarantee, existing approaches add noise to each node’s da...