網際網路秘密投票之研究

Abstract

Secret balloting through the Internet is not only a technical evolution, but also a social activity realizable in the near future. We consider four phases necessary to complete the evolving progress: (1) theoretical research, (2) development and implementation of prototype systems, (3) trial experiments on pilot systems, and (4) promotion toward widespread acceptance from the society. In this dissertation, we refine a theoretic protocol, implement a prototype system based on the revised protocol, and conducIn the effort of theoretic improvement, we revise the order of Mixer's procedures in Hwang's protocol [36] to enhance privacy of ballots. In addition, we design in details authorities' acknowledgments and evidences. Therefore, through the extension of Hwang's protocol, a voter can protect his legal right of keeping his ballot private and verifying his vote on the one hand; on the other, authorities can prevent themselves from malfeasant accusation. In the effort of system implementation, we develop a secret balloting system for group decision environment. To investigate user attitude toward a secret balloting system, we conduct a questionnaire with the prototype system and specify students of Institute of Information Management in NCTU as our sample. From this investigation we arrive at a conclusion that for users with more experiences of using computers, a secret balloting system provides as much anonymity as does a questionnaire.A limit of our current prototype system is that it does not provide the functions of receipt-free and universal verifiability. As a result, it is not suitable for a large-scale election. The experimental result proves our system operational, so we suggest that the system be used in a group decision environment.In our solution, voters can prove their votes to the court, and accuse the cheating official. Now, we don't have any acceptable solution to receipt-free and universal verifiability, we would study more related literatures and try to propose some solutions. When we can propose a solution satisfied both receipt-free and universal verifiability. We also would like to revise our secret balloting system for a large-scale election.