The Research Of Verifiable Secret Sharing Without A Trusted Party

With the development of computer network technology, the security and protection problem of the important or sensitive information become increasingly severe. Secret sharing is an important means in information security and data secrecy. It can decentralize responsibility and improves system's security.In this thesis, we firstly expatiate on cryptology knowledge, and then we introduce the main idea of threshold secret sharing, and discuss some typical threshold secret sharing schemes. To resolve these schemes' problems; we propose a verifiable secret sharing scheme without a trusted part. And this scheme has the following features:1. Using secret sharing model without a trusted part in this scheme. Since without a trusted part, each member is the dealer of secret distribution and also the participant of secret reconstruction. Therefore, it can eliminate authority cheating thoroughly.2. Using two generators and zero-knowledge proof verifiable methods in this scheme. Therefore, it improves scheme's justness and security. By using two generators verifiable method, it can verify that whether the sub share is correct and prevents the dishonest member from cheating. By using zero-knowledge proof verifiable method, it can verify that whether the member has correct share and does not reveal any useful information about the share and prevents the dishonest member from cheating.We use VC++6.0 to design a prototype system based on this scheme in Windows XP. The result shows that our scheme is right and feasible, and has good justness and security. At last, we summarize our dissertation and expect the future of secret sharing.