KUNCI RAHASIA DALAM KONSTRUKSI SKEMA PEMBAGIAN RAHASIA; A SECRET KEY IN CONSTRUCTING A SECRET SHARING SCHEME

Al.Sutjijana, Subanar

2015 | Tesis | FMIPA

Secret Sharing Scheme is a method of distributing a secret or a password to a group of participants in such away that every participant gets a share of the secret such that only qualified subsets of participants can recover the secret by combining their shares. In general secret sharing schemes, a dealer D chooses a secret key K, and then secretly distributes the shares of the secret to a set of all participants P. It is assumed that D =2 P. Some day in the future, some of participants, incorporated in a set B, combine their shares. In threshold scheme with access level t, if the cardinality of B is greater or equals to t then all of the participants in B can recover the secret K by combining all their shares. However if the cardinality of B is less than t then the participants in B can not get any information about the secret K. In Shamir’s secret sharing schemes, called (t;w)-threshold scheme, the dealer determines finite field GF(p) = Zp with p is a prime and p ? w + 1. The dealer chooses a secret polynomial of degree t

Kata Kunci : Secret Sharing Scheme; threshold scheme, finite field, Vandermonde determinant.