Quantum Secret Sharing Protocol Based On Entangle States

We brievely introduce the history and present situation of quantum cryptography, and make efforts in discussions and researches of quantum secret sharing protocols. Nowadays, quantum cryptography attracts more and more people for its high quality and threaten to classical cryptography. The discovery of Shor algorithm poses a big threat to RSA protocol which is based in factorization of large prime numbers. Meanwhile, quantumn cryptography is unbreakable in principle, so should be very useful in the near future.Quantum secret sharing is using the quantum theory to realize the secret sharing protocol. Alice wants to share some secrets between Bob and Charlie, while each one couldn’t get the secret without the other one’s help. Quantum secret sharing has some natural advantage comparing with classical secret sharing. For example, the parity in multipartite communications, and the security of message in sending particles.Y. S. Zhang bring out the direct communication protocol using reusable preshared entangle states as carriers in2001, while protect the monitor of eavesdropper based on Hadamard operation between each odd round and even round. Karimipour applied this to quantum secret sharing (QSS), made it efficiently and reliebly. While, there is a serious loophole in this kind of protocols, such that eavesdropper can use intercept-entangle-resend strategy to hide its existence from monitor. We figure out this loophole and send an correction method, then argue that the amount of transmitted information is as much as in the origin protocol.