Brent, R.P. and Zimmermann, P. (2003) Algorithms for Finding Almost Irreducible and Almost Primitive Trinomials. In: Van Der Poorten, A., Van Der Poorten, A.J., Stein, A. and Williams, H.C., Eds., High Primes and Misdemeanours: Lectures in Honour of the 60th Birthday of Hugh Cowie Williams, American Mathematical Society, Providence, 91-102.

has been cited by the following article:

• TITLE: Search for Monic Irreducible Polynomials with Decimal Equivalents of Polynomials over Galois Field GF(pq)

  AUTHORS: Sankhanil Dey, Ranjan Ghosh

  KEYWORDS: Finite Fields, Galois Fields, Irreducible Polynomials, Decimal Equivalents

  JOURNAL NAME: Open Journal of Discrete Mathematics, Vol.8 No.1, January 29, 2018

  ABSTRACT: Substitution boxes or S-boxes play a significant role in encryption and de-cryption of bit level plaintext and cipher-text respectively. Irreducible Poly-nomials (IPs) have been used to construct 4-bit or 8-bit substitution boxes in many cryptographic block ciphers. In Advance Encryption Standard, the ele-ments of 8-bit S-box have been obtained from the Multiplicative Inverse (MI) of elemental polynomials (EPs) of the 1st IP over Galois field GF(28) by adding an additive element. In this paper, a mathematical method and the algorithm of the said method with the discussion of the execution time of the algorithm, to obtain monic IPs over Galois field GF(pq) have been illustrated with example. The method is very similar to polynomial multiplication of two polynomials over Galois field GF(pq) but has a difference in execution. The decimal equivalents of polynomials have been used to identify Basic Polynomials (BPs), EPs, IPs and Reducible polynomials (RPs). The monic RPs have been determined by this method and have been cancelled out to produce monic IPs. The non-monic IPs have been obtained with multiplication of α whereα∈ GF(pq)and assume values from 2 to (p − 1) to monic IPs.