Security decision analysis based on A. Shamir´s (t, n) threshold secret sharing scheme

Decentralized storage for the key can help improving its security. This essay is based on A. Shamir´s threshold key sharing scheme, focus on the influence (the key, subtle and vague) on the security and ease of use for tn value´s selection, added with the third index of the Yager Fuzzy Theory, and combined with the exact value´s complementary judgment matrix, to build a preferred method for the selected alternatives of the strategic decision scheme in the threshold key sharing scheme. The last part of the essay illustrates the feasibility and effectiveness of this method by example.