Since the time public-key cryptography was introduced by Diffie andHellman in 1976, numerous public-key algorithms have been proposed. Some of thesealgorithms are insecure and the others that seem secure, many are impractical, eitherthey have too large keys or the cipher text they produce is much longer than theplaintext. This paper focuses on efficient implementation and analysis of two mostpo...

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 securi...

Cryptographic computations (decryption, signature generation, etc.) are often performed on a relatively insecure device (e.g., a mobile device or an Internet-connected host) which cannot be trusted to maintain secrecy of the private key. We propose and investigate the notion of key-insulated security whose goal is to minimize the damage caused by secret-key exposures. In our model, the secret k...

Recently Landau and Diffie gave in a series of articles in the Notices of the American Mathematical Society [DL02, Lan01, Lan00a, Lan00b] and in the American Mathematical Monthly [Lan04] excellent expositions on how the theory of multivariable polynomials are used in cryptography. However they covered only half of the story. They covered only the theory of polynomials in symmetric or secret cry...

As the title says, this book is about Multivariate cryptography. Besides code-, latticeand hash-based cryptosystems, Multivariate cryptography is one of the main fields of cryptosystems which are believed to be secure against attacks with quantum computers. Multivariate cryptography deals with systems of nonlinear polynomial equations in several variables over a finite field which are difficult...

This paper presents a new paradigm of cryptography, quantum public-key cryptosystems. In quantum public-key cryptosystems, all parties including senders, receivers and adversaries are modeled as quantum (probabilistic) poly-time Turing (QPT) machines and only classical channels (i.e., no quantum channels) are employed. A quantum trapdoor one-way function, f , plays an essential role in our syst...

The cryptographic community has developed many tools to incorporate distributed trust mechanisms into cryptographic primitives and protocols as well as primitives where parties are naturally distributed. Since the fastest growing paradigm in computing is distributed systems and communication networks, the importance of distributed mechanisms has been increasing, and will likely to be pervasive ...