Research On Secure Electronic Voting Protocol

Modern society demands more efficient and convenient way of dealing with everyday affairs. As a result, traditional paper-voting cannot satisfy modern voting's demand. Thanks to the rapid development of computer technology and improvement of network environment, electronic voting based on computer network technology emerges. However, there is one misunderstanding on electronic voting:electronic voting is non-paper voting system based on computer network technology. The earliest strict definition of electronic voting was introduced by Chaum. That is, electronic voting system is based on cryptography and voting is through internet. Secure voting scheme should be legal, robust, fair, anonymous and complete. According to recent research, the characteristics of receipt-freeness, incoercibility and democracy bring the concept of electronic voting to gradual perfection. At present, many net voting systems have been put to use. But strictly speaking, these systems don't belong to the rank of electronic voting. There are a lot of shortcomings in protocols and function should be improved forwardly. For example, voters may vote more than once, in order to increase the candidates'Number; the way of identity authentication is not flexible enough; the transmission of voting result cannot be verified; the process of recounts is not transparent to voters, and they couldn't make sure the correctness of the result; personal information may be leaked out during accusation; no more than one vote can be sent off from the same IP, which restrict the use of one computer by more than one voters and brings some inconvenience.This thesis consists of three important parts:According to the characteristics of miscellaneous identity authentication techniques, the first part probes into these domains with the combination of the features of the electronic voting:1.It analyzes the fundamental concepts of identity certificate-based authentication,password-based authentication,smart card based authentication and biometric authentication as well as their design principles respectively. Meanwhile it also points out the merits and drawbacks of the above-mentioned subjects with the consideration of security, practicality and cost.2. This part demonstrates the concrete model of modern identity certificate-based authentication in detail, making use of identity certificate to solve the problems rising from the identity authentication in electronic voting and describing the advantages of identity certificate in the application of the electronic voting protocols. In the meantime, combined with the design requirements of the electronic voting, this section also highlights the defects and potential security hazards lurking under the certain circumstances such as:various application environment,channel assumption,the honesty of participant and malicious attack.3. This part makes a presentation of four familiar OTP authentication protocols in an easy-to-understand fashion, utilizing the disposable and dynamic features of OTP authentication to apply the OTP technique to the electronic voting schemes, in this way, the electronic voting identity certificate can be achieved effectively in the network environment. However, when used in the electronic voting, OTP will generate the problems like repeated ballot and impossibility of mutual authentication from time to time.The second part of the thesis puts forward an electronic voting scheme based on the SOTP, which possesses the following features:1. It sets up a new authentication architecture, using the combination of the uniqueness of identity certificate and the dynamic of SOTP to accomplish the voters' identity authentication.2. Registration Authority works in concert with CA (Certificate Authority) to judge the validity of the ballot, warding off the repeated ballot.3. During the public verification, this scheme can harness SOTP to appeal secretly, which is not only able to guarantee the correctness of tally, but also can prevent private information of the voters from leaking.The third part comes up with an electronic voting scheme on the basis of point-inclusion protocol, which has the features in possession as follow: 1. It introduces decision tools of point inclusion to the electronic voting, using the XY coordinates as affirmative vote/opposing vote as well as furnishing the electronic voting with a new form of ballot, which is more convenient to calculate thus offering a new mode of tally.2. It owns the authority bulletin board with the features of timed commitments; the bulletin board can display different information in the light of each voting phase. By using this item, with unique management authority, different participants will be able to possess different voting information, which in turn prevents private information from leaking.3.It achieves the coercion-resistant and receipt-freeness in the electronic voting by using random number r to interfere with the calculation (x', y')= (x+r, y+r) rendering a new method to meet the demands of the receipt-freeness of the electronic voting.