Research On Secret Sharing Scheme

In the modern society, along with the development of science and technology, Internet plays a more and more important role in people's life. The confidentiality, integrity and availability of information must be satisfied when important data are transferred by Internet. The conventional way to deal with this problem is to use the technique of information security, and cryptography is the core of information security.Secret sharing is an important branch in cryptography as well as a very important research field in information security. It is a technology of sharing secret among a group of participants. Their major function is to protect important information from missing, being destroyed and being changed. The work flow of a common secret sharing scheme(also known as threshold scheme) is as follows:one message is divided into n segments, each of which is referred to a shadow. This message can be reconstructed with t shadows and can't be reconstructed with t-1 shadows. It is also called as (t,n) threshold scheme.In fact, secret sharing schemes have a wide range of applications requiring the concurrence of several designated people to be initiated, such as processing a banking business, opening a government vault and launching a missile. If some important documents or information is held by some individual alone, it is very dangerous. The proper method is charged by several people.In this paper, the concept of secret sharing and its actualities and background are introduced, the shortcomings of existing secret sharing schemes in practice are analyzed. Aiming at these problems, we designed a cheating-proof secret sharing scheme capable of differentiating the roles of the secret sharers. Main contributions of this scheme are summarized as follows:1. There are numerous secret sharers that play different roles, and a shared secret can be reconstructed so long as it is admitted by any individual in each group.2. It can be verified whether the secret sharers possess valid secret segments and what are their roles and competency without demanding the secret sharers to disclose their respective secret.3. The digital signature can be realized conveniently. In this scheme, the private key of sharers diverse from each other, and they are ever unknown to the key splitter, but it can be known which member playing certain role participates in the message restoration according to the digital signature.