A t-out-of-n secret-sharing scheme allows an honest dealer D to distribute a secret s among n players, such that any subset of t players has no information about s, but every set of t + 1 players can collaboratively reconstruct the secret. The most famous secret-sharing scheme is Shamir’s Sharing Scheme [Sha79] (cf. Section 7.1.2). It uses polynomials to obtain the desired properties. Before pr...

Identity based cryptosystem simplifies the key management and revocation problem. Here we propose an Identity Based Strong Designated Verifier Signature (IBSDVS) scheme using bilinear pairings. The Designated Verifier Signature scheme described in [10] is identity based but it suffers from the deligatability as pointed out in [4]. We analyse the security of the scheme and show that the problem ...

Recently, an image encryption scheme based on rotation matrix bit-level permutation and block diffusion was proposed [Y Zhang, D Xiao. Commun Nonlinear Sci Numer Simulat. 2014, 19:74-82]. In this paper, this image encryption scheme was studied in detail and its defects of low encryption speed and weak security were pointed out. This scheme with one round was crypt-analyzed successfully with the...

In 2003, Shen et al. proposed an improvement on YangShieh’s timestamp-based password authentication scheme using smart cards. Then they claimed that their scheme cannot withstand a forged login attack, but also eliminate a problem of Yang-Shieh’s. However, their scheme is still susceptible to forged login attack. In this letter, we show how the forged login attack can be worked out on Shen et a...

In this paper we provide a quantum information delay scheme using orthogonal product states. By sharing orthogonal product states one person can give the other person some information which cannot be read until he or she lets the latter do. The fundamental Laws of quantum mechanics guarantee that the scheme is unconditionally secure. Our scheme is easy to carry out in practice because there are...

This paper presents an improvement of the Visual Pattern image coding (VPIC) scheme presented by Chen and Bovik in [2] and [3]. The patterns in this improved scheme are defined by morphological operations and classified by absolute error minimization. The improved scheme identifies more uniform blocks and reduces the noise effect. Therefore, it improves the compression ratio and image quality i...

In this paper, we point out the security weaknesses of Chen et al.’s e-voting scheme. We give a modification which satisfies the security requirements of a e-voting scheme.

A t-out-of-n secret-sharing scheme allows an honest dealer D to distribute a secret s among n players, such that any subset of t players has no information about s, but every set of t + 1 players can collaboratively reconstruct the secret. The most famous secret-sharing scheme is Shamir’s Sharing Scheme [Sha79] (cf. Section 8.1.2). It uses polynomials to obtain the desired properties. Before pr...

The details of an external quality assessment scheme in histopathology based on district general hospitals in south west England are described. The scheme is supplementary to internal audit carried out in individual departments.

In 2004, Tzeng, Yang and Hwang proposed a nonrepudiable threshold multi-proxy multi-signature scheme with shared verification. However, Bao, Cao and Wang pointed out that Tzeng et al.’s scheme cannot resist frame attacks and therefore presented an improved version. In this paper, we will show that there is another security flaw existing in both Tzeng et al.’s scheme and Bao et al.’s scheme.