紀要論文

Almost Optimal Cheating-Detectable (2, 2, n) Ramp Secret Sharing Scheme

不正検知可能な準最適 (2, 2, n) ランプ型秘密分散

eng

24321192

https://doi.org/10.15002/00022721

法政大学大学院情報科学研究科

法政大学大学院紀要. 情報科学研究科編

15

1

6

2020-03-24

Version of Record

In this research, we consider a strong ramp secret sharing scheme that can detect cheating. A cheating-detectable (k, L, n) ramp secret sharing scheme has been studied so far, and a strong ramp secret sharing scheme which achieves lower bounds on the size of shares and random number used in encoding (i. e., share generation), and the success probability of impersonation attack has been presented. Now a challenging task is to achieve the lower bound on the success probability of substitution attack. In this paper, we present a strong (2, 2, n) ramp secret sharing scheme that almost achieves the lower bound on the success probability of substitution attack. The proposed scheme is the first to almost achieve the lower bound. Moreover the proposed scheme also achieves other lower bounds such as those on the size of shares and random number used in encoding, and the success probability of impersonation attack. We take a unique strategy to construct the scheme. Most existing works present generic type verification functions which can detect cheating for any linear and strong (k, L, n) ramp scheme. On the other hand, our proposed verification function (one of those which we call limited type verification functions) can detect cheating when used with a linear and strong (2, 2, n) ramp scheme satisfying a certain property.

Article

AA12746425