A distributed key generation (DKG) protocol is a central component in distributed cryptosystems. It allows a group of participants to jointly generate a pair of keys (private key and public key) without assuming any trusted participant. The public key is output in clear but only authorised subgroups of participants are able to reconstruct or use the private key. Existing literature on DKG proto...

It is widely believed to take exponential time to find a solution of a system of random multivariate polynomials because of the NP-completeness of such a task. On the other hand, in most of multivariate public key cryptosystems proposed so far, the computational complexity of cryptanalysis is apt to be polynomial time due to the trapdoor structure. In this paper, we develop the concept, piece i...

In this paper we present a general framework for constructing efficient multicast cryptosystems with provable security and show that a line of previous work on multicast encryption are all special cases of this general approach. We provide new methods for building such cryptosystems with various levels of security (e.g., IND-CPA, IND-CCA2). The results we obtained enable the construction of a w...

Certificateless public-key cryptosystem is a recently proposed attractive paradigm using public key cryptosystem, which avoids the key escrow inherent in identity-based public-key cryptosystems, and does not need certificates to generate trust in public keys. Recently, Al-Riyami and Paterson proposed a new certificateless public-key encryption scheme [2, 3] and proved its security in the random...

In this paper we will construct a lattice-based public-key cryptosystem using non-commutative quaternion algebra, and since its lattice does not fully fit within Circular and Convolutional Modular Lattice (CCML), we prove it is arguably more secure than the existing lattice-based cryptosystems such as NTRU. As in NTRU, the proposed public-key cryptosystem relies for its inherent security on the...

Since ancient times, there has been a tug-of-war taking place between code makers and code breakers. Only within the last fifty years have the code makers emerged victorious (for now that is) with the advent of public key cryptography. This paper surveys the mathematical foundations, shortcomings, and novel variants of the “first” public key cryptosystem envisioned by Whitfield Diffie, Martin H...

Authentication and Confidentiality is the main goal of the public key cryptosystems deal when communication takes place between both the parties. The mostly used cryptographic methods are broadly classified as symmetric and asymmetric. The DES comes under the category of symmetric key cryptosystem whereas RSA, NTRU[1] belongs to the category of asymmetric key cryptosystem. NTRU (Nth degree trun...

In this paper we propose a new side channel attack, where exponent recodings for public key cryptosystems such as RSA and ECDSA are considered. The known side channel attacks and countermeasures for public key cryptosystems were against the main stage (square and multiply stage) of the modular exponentiation (or the point multiplication on an elliptic curve). We have many algorithms which achie...

p. 1 The Security of Public Key Cryptosystems Based on Integer Factorization p. 9 A Uniform Approach to Securing Unix Applications Using SESAME p. 24 Integrated Management of Network and Host Based Security Mechanisms p. 36 Covert Distributed Computing Using Java Through Web Spoofing p. 48 Differential Cryptanalysis of a Block Cipher p. 58 On Private-Key Cryptosystems Based on Product Codes p. ...