Design Of Electronic Auction Protocols By Using ElGamal Cipher

Electronic auction, which is the auction on the Internet, is one of the most important parts in Electronic commerce. It brings the largest economic benefits to both a buyer and a seller, and avoids a bidder's presence at the auction scene.Electronic auction protocol, oriented to the application layer, is used to guarantee the integrality, security of the communication messages and the privacy of the bidders on the Internet. So how to construct a secure and efficient electronic auction protocol, to prevent the malicious attacks and guarantee the business on the Internet, is attracting more and more attentions in recent years. The main work in the dissertation are as follows:(1)In order to solve the following problems:①most protocols published rely on threshold computation, privacy problem is not well solved;②when there is no auctioneers in the protocol, the computation is too complex, a simple protocol without auctioneers was proposed in the dissertation;(2)The author developed the first protocol to another protocol, in which a bidder can decide how many items to buy according to different bidding prices, after analyzing the previous protocols that merely considered this question;(3)It does harm to a bidder that he/she has to choose a bid in the bid space, which is set by the seller before auction. So in order to protect the bidder's profit, a protocol under which each bidder could freely submit his/her bid according to his/her willingness was proposed.