Recent breakthroughs concerning the current standard SHA-1 prompted NIST to launch a competition for a new secure hash algorithm [1,13]. Provably secure hash functions (in the sense that their security relates to the hardness of some mathematical problems [5,7,9,12]) are particularly interesting from a theoretical point of view but are often much slower than heuristic functions like SHA. In thi...

Multivariate hash functions are a type of hash functions whose compression function is explicitly defined as a sequence of multivariate equations. Olivier Billet etc. have designed the hash function MQ-HASH and Jintai Ding etc. also propose a similar construction, which the security depends on the difficulty of solving randomly drawn systems of multivariate equations over a finite field. Findin...

In this article, we analyze the security of the GOST hash function with respect to (second) preimage resistance. The GOST hash function, defined in the Russian standard GOST-R 34.11-94, is an iterated hash function producing a 256-bit hash value. As opposed to most commonly used hash functions such as MD5 and SHA-1, the GOST hash function defines, in addition to the common iterated structure, a...

the unitary cayley graph xn has vertex set zn = {0, 1,…, n-1} and vertices u and v areadjacent, if gcd(uv, n) = 1. in [a. ilić, the energy of unitary cayley graphs, linear algebraappl. 431 (2009) 1881–1889], the energy of unitary cayley graphs is computed. in this paperthe wiener and hyperwiener index of xn is computed.

Hash functions are fundamental components of many cryptographic applications. Due to the recent attacks on classical designs, alternative design approaches are proposed. In this paper, we give a survey for hash function constructions based stream ciphers mainly concentrating on Panama, RadioGatún and RC4-hash. Also, we propose an example hash function Dragon-Hash based on the stream cipher Dragon.

We propose a new cryptographic construction called 3C, which works as a pseudorandom function (PRF), message authentication code (MAC) and cryptographic hash function. The 3Cconstruction is obtained by modifying the Merkle-Damg̊ard iterated construction used to construct iterated hash functions. We assume that the compression functions of Merkle-Damg̊ard iterated construction realize a family of ...

A chameleon-hash function is a hash function that involves a trapdoor the knowledge of which allows one to find arbitrary collisions in the domain of the function. In this paper, we introduce the notion of chameleon-hash functions with ephemeral trapdoors. Such hash functions feature additional, i.e., ephemeral, trapdoors which are chosen by the party computing a hash value. The holder of the m...

This paper describes the study of cryptographic hash functions, one of the most important classes of primitives used in recent techniques in cryptography. The main aim is the development of recent crypt analysis hash function. We present different approaches to defining security properties more formally and present basic attack on hash function. The Main aim of this paper is the development of ...

The unitary Cayley graph Xn has vertex set Zn = {0, 1,…, n-1} and vertices u and v are adjacent, if gcd(uv, n) = 1. In [A. Ilić, The energy of unitary Cayley graphs, Linear Algebra Appl. 431 (2009) 1881–1889], the energy of unitary Cayley graphs is computed. In this paper the Wiener and hyperWiener index of Xn is computed.