Degree of Regularity for HFEv and HFEv-
نویسندگان
چکیده
In this paper, we rst prove an explicit formula which bounds the degree of regularity of the family of HFEv ( HFE with vinegar ) and HFEv( HFE with vinegar and minus ) multivariate public key cryptosystems over a nite eld of size q. The degree of regularity of the polynomial system derived from an HFEvsystem is less than or equal to (q − 1)(r + v + a− 1) 2 + 2 if q is even and r + a is odd,
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