The Research Of Secret Sharing Encryption Without Trusted Center

Secret sharing is an important part of modern cryptography. It is also an important research direction of the information security. Secret sharing is used for saving secret information. It prevents excessive concentration of power being abused and can disperse responsibility. On the other hand, it guarantees the security and robustness of data. Therefore, research of secret sharing has important theoretical significance and broad application prospects.This thesis introduces several typical threshold secret sharing schemes , with several important directions of threshold secret sharing is discussed further in detail. In regard to the shortcomings existed in these schemes, a secret sharing encryption scheme is proposed without trusted center. There are some features in the scheme as follows:(1) Since without a trusted part, the secret sharing generated by the members of the cooperative. Therefore, it can eliminate authority cheating thoroughly; User decrypt ciphertext with system private key; In the decryption process, t or more members can indirectly solve ciphertext;(2) The scheme bases on ellipite curve cryptosystem,ECC that is compared with the RSA and Elgamal cryptosystem,which can use shorter keys to achieve the same security, so security and efficiency is further enhanced;The generation and realization algorithms of the large prime number are introduced in the dissertation. In Windows XP, a prototype system is implemented by using VC++6.0. The experimental results show that the scheme is correct and feasible and has good security and applicability.At last, we summarize our disseratation and expert the future of secret sharing.