Due to the mature of networks and communication technologies, electronic commerce is growing up rapidly and many advanced applications in electronic commerce are developed recently, such as on-line shopping, on-line bidding, and on-line gambling. There are numerous types of gambling like typical lottery, sport lottery, and poker gambling where our research will focus on the lottery games. Because of some special characteristics of the lottery games such as fairness and anonymity, it is hard to design a perfect electronic lottery protocol. The transaction mechanism in an electronic lottery protocol is an important issue since it will affect the benefits of customers if it is not fair or secure. The generating of random winning numbers in a lottery game has been discussed in many papers, but the fairness and anonymity for purchasing tickets and claiming the prizes are only discussed in few papers where these previous results cannot completely cope with the problems of fairness and anonymity. In the thesis, we will propose two electronic lottery protocols that can achieve the fairness and perfect anonymity simultaneously.

Due to the flush development of academic research, a great deal research results have been published in conference proceedings and journals. However, these articles need to be inspected by some professionals in specific fields. It is the most important that fairness must be guaranteed during the entire process of reviewing. Nevertheless, the privacy of reviewers may be leaked out because that the reviewers must sign their comments on the reviewed papers. The leakage of the reviewers' privacy may affect the judgement of the reviewers on the papers. In addition, the authors of a paper have to show their names to the editor of a conference proceedings or a journal when submitting the paper, so that it may also affect the decision of the editor on this paper. The major reason of the above problems is that the privacy or anonymity of the reviewers and the authors is not protected well, such that the reviewers and the editor cannot perform the reviewing processes without disturbance. In order to cope with the problems, we deeply analyze the privacy issue in the paper review system and then propose a generic idea, which is independent of the underlying cryptographic components, to achieve the anonymity property and other key requirements in a secure paper review scheme.