Two Types Of Secret Sharing Scheme

Secret sharing occupies a significant position in modern crypotography, which means the strategy of sharing a secret among a group of participants. Each participant holds a part of the secret which is called share or shadow. Secret sharing technology reaches the goal of not putting all eggs in the same basket. The secret can be recovered even if when certain participant does some cheat or his share loses. In fact, it improves data services' reliability by bringing in redundancy. Since Shamir and Blakley introduced secret sharing schemes in 1979 separately, a lot of authors have thrown themselves into the study of secret sharing and have gained fruitful achievements.However, existing secret sharing schemes have the following disadvantages in common:(1) While sharing secret, the dealer and the participants in many schemes can't be tested whether they are honest or not, which causes the hidden threat to the safety of secret.(2) Some secret sharing schemes can't defend against the adversaries' assault, which would bring some troubles for the confideness of secret.(3) When access structure and adversary structure are both considered, almost existing schemes can't be applied directly.To solve above weakness, the article will consider the verifiable and dynamic multi-secret sharing, anti-assaut multi-secret sharing and satisfying access structure and adversary structure schemes as key point in the research, the research findings of this paper are shown in the following:(1) In order to deal with the problems of GE Li-na and TANG Shao-hua's secret sharing schemes, this paper proposes a verifiable and dynamic threshold secret sharing scheme based on RSA cryptographic system and intractability of discrete logarithm. In this scheme, the scheme is able to verify whether all participants are honest or not and every participant is also able to check whether others' secret shares are valid or not as well as satisfying other properties of GT scheme, which enhance the possibility of reconstructions' success and the scheme's efficiency, therefore, the scheme is highly security and practicality.(2) We present two anti-assault dynamic multi-secret sharing schemes that are based on the weight of participants are the same and are not by RSA, discrete logarithm cryptosystem, hash function and XOR operation. Compared with the existing schemes, the dealer only sends pseudo secret shares to participants in our schemes, which makes them be more strongly in anti-assault; moreover, the scheme 1 is dually anti-assault.Above all, in the whole dynamic process, the coefficients of polynomials and original secret shares always stay the same, which reduces the cost of realizing the schemes.(3) Associated with elliptic curve and bilinear mapping, we present a multi-secret sharing scheme based on adversary structure by bringing in redundancy. When access structure and adversary structure are both considered, our schemes can be applied directly, which makes the secret sharing management more effective and safe.