Cryptography Reading Group - Jean Belo Klamti

Thursday, June 9, 2022 11:30 am - 11:30 am EDT (GMT -04:00)

Title: Generalized Subspace Subcode with Application in Cryptology

Speaker: Jean Belo Klamti
Affiliation: University of Waterloo
Attend: Contact Jesse Elliott

Abstract:

Most codes with an algebraic decoding algorithm are derived from Reed-Solomon codes. They are obtained by taking equivalent codes, for example Generalized Reed-Solomon codes, or by using the so-called subfield subcode method, which leads to Alternant codes over the underlying prime field, or over some intermediate subfield. The main advantage of these constructions is to preserve both the minimum distance and the decoding algorithm of the underlying Reed-Solomon code.

In this paper, we explore in detail the subspace subcodes construction. This kind of codes was already studied in theparticular case of cyclic Reed-Solomon codes. We extend this approach to any linear code over the extension of a finite field. We are interested in additive codes who are deeply connected to subfield subcodes. We characterize the duals of subspace subcodes. We introduce the notion of generalized subspace subcodes. We apply our results to Generalized Reed-Solomon codes which leads to codes with interesting parameters, especially over a large alphabet. To conclude our paper, we discuss the security of the use of generalized subspace subcodes of Reed-Solomon codes in a cryptographic context.