1 out of n Conditional Oblivious Cast Protocol

• Main Authors: Rih-Chen Liao, 廖日辰
• Other Authors: Narn-Yih Lee
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/48360116987447979838

碩士 === 南台科技大學 === 資訊管理系 === 95 === Oblivious transfer protocol is an important basic technology in cryptography. It includes two parties: Sender and Receiver, where sender wants to convey secret values to receiver, and receiver can choose the secret value he wanted. But the sender cannot know which secret value the receiver chose. Moreover, the receiver cannot get any secret values that he did not choose. According to the amount of information that the sender holds and the amount of information that the receiver can choose, oblivious transfer protocols canbe classified as original oblivious transfer plotocol, 1 out of 2 oblivious transfer protocol, 1 out of n oblivious transfer protocol and t out of n oblivious transfer protocol. Conditional oblivious transfer protocol is that a public predicate is used to evaluate the sender’s and receiver’s inputs, and Construction of conditional oblivious cast protocol is another varicnt of the COT. Those protocols are proposed in the types of 1 out of 2 conditional oblivious transfer protocol and 1 out of 2 conditional oblivious cast protocol. This thesis will propose a 1 out of n conditional oblivious transfer protocol and a 1 out of n conditional oblivious cast protocol by using additive homomorphic encryption and multiplicative homomorphic encryption technologies. Thes protocols can be used to enhance the efficiency and extend the applied enuironanent of oblivious transfer.