S. Tiwari

activity

20172025

most citedAn algebraic attack to the Bluetooth stream cipher E0

1 citations · 1 across the 9 of their papers we have counts for

collaborators

12 papers

cs.CR2025

Oracle-Based Multistep Strategy for Solving Polynomial Systems Over Finite Fields and Algebraic Cryptanalysis of the Aradi Cipher

Roberto La Scala, Sharwan Kumar Tiwari

The multistep solving strategy consists in a divide-and-conquer approach: when a multivariate polynomial system is computationally infeasible to solve directly, one variable is ass…

math.NT2024

On $r$ -primitive $k$ -normal polynomials with two prescribed coefficients

Avnish K. Sharma, Mamta Rani, Sharwan K. Tiwari +1

This article investigates the existence of an $r$ -primitive $k$ -normal polynomial, defined as the minimal polynomial of an $r$ -primitive $k$ -normal element in $F_{q^{n}}$ , w…

cs.SC2023

A multistep strategy for polynomial system solving over finite fields and a new algebraic attack on the stream cipher Trivium

Roberto La Scala, Federico Pintore, Sharwan K. Tiwari +1

In this paper we introduce a multistep generalization of the guess-and-determine or hybrid strategy for solving a system of multivariate polynomial equations over a finite field. I…

math.NT2022

Inverses of $r$ -primitive $k$ -normal elements over finite fields

Mamta Rani, Avnish K. Sharma, Sharwan K. Tiwari +1

Let $r$ , $n$ be positive integers, $k$ be a non-negative integer and $q$ be any prime power such that $r ∣ q^{n} - 1.$ An element $α$ of the finite field $F_{q^{n}}$ is called…

cs.CR2022★ 1 cited

An algebraic attack to the Bluetooth stream cipher E0

Roberto La Scala, Sergio Polese, Sharwan K. Tiwari +1

In this paper we study the security of the Bluetooth stream cipher E0 from the viewpoint it is a "difference stream cipher", that is, it is defined by a system of explicit differen…

cs.CR2021

INRU: A Quasigroup Based Lightweight Block Cipher

Sharwan K. Tiwari, Ambrish Awasthi, Sucheta Chkrabarti +1

In this paper, we propose a quasigroup based block cipher design. The round functions of the encryption and decryption algorithms use quasigroup based string transformations. We sh…

math.NT2021

Primitive Normal Values of Rational Functions over Finite Fields

Avnish K. Sharma, Mamta Rani, Sharwan K. Tiwari

In this paper, we consider rational functions $f$ with some minor restrictions over the finite field $F_{q^{n}},$ where $q = p^{k}$ for some prime $p$ and positive integer $k$ .…

math.CO2021

Algebraic Properties of Subquasigroups and Construction of Cryptographically Suitable Finite Quasigroups

V. A. Artamonov, Sucheta Chakrabarti, Sharwan K. Tiwari +1

In this paper, we identify many important properties and develop criteria for the existence of subquasigroups in finite quasigroups. Based on these results, we propose an effective…

cs.CR2020

Stream/block ciphers, difference equations and algebraic attacks

Roberto La Scala, Sharwan K. Tiwari

In this paper we model a class of stream and block ciphers as systems of (ordinary) explicit difference equations over a finite field. We call this class "difference ciphers" and w…

math.RA2018

Noncommutative algebras, context-free grammars and algebraic Hilbert series

Roberto La Scala, Dmitri Piontkovski, Sharwan K. Tiwari

In this paper we introduce a class of noncommutative (finitely generated) monomial algebras whose Hilbert series are algebraic functions. We use the concept of graded homology and…

math.RA2017

Multigraded Hilbert Series of noncommutative modules