The Research Of Traceable Anonymous Electronic Voting Protocol

Voting is one of the most important tools for democracy and it is always in ourlife. In traditional voting, voters should go to the vote-station and may queue for along time in a large scale voting. As the rapid development of computer and networktechnology, voting is imminent to take the next step towards electronic form. In thiskind of voting, electronic ballot is used and counted by computers. By the help ofcryptography and network technology, electronic voting allows voter cast their ballotsin any place that linked into Internet. Compared with the traditional form, electronicvoting is more convenient and efficient. Secure protocol is the core item of theelectronic voting. This paper introduces previous electronic voting protocols, andanalyzes the security requirements of them. A new electronic voting protocol ispresented that called TAEV (traceable anonymous electronic voting) protocol.Our work includes the following aspects:Firstly, TAEV protocol is presented, This protocol uses blind signature and keyescrow to provide anonymity and traceability. Cut-and-choose is used to protectreceipt-freeness. Secure multi-party computation and homomorphic commitment areintroduced in TAEV to achieve universal verifiability. We divide the power ofauthorities by using secret sharing that can prevent corruption. There are four phasesin TAEV: registration phase, vote phase, tally phase and trace phase. The voter willget a new certificate that can protect his/her anonymity in registration phase and castthe ballot in vote phase. In tally phase ballots will be counted and the result will bepublished. The administrator can trace some of the ballots in trace phase if necessary.Secondly, We analyse the security of TAEV and compare it with some typicalprotocols. TAEV can satisfy most properties including anonymity, traceabilityreceipt-freeness etc. based on a group of assumptions. Compared with previousprotocols, TAEV can satisfy more security properties or satisfy the same securityproperty in a lower assumption.Thirdly, a PEQDL-based registration sub-protocol is designed as an option ofregistration phase to reduce reliance on assumptions. Proof of equality of discretelogarithms (PEQDL) is used to bind the private key of identity and vote certificatesand that make TAEV no longer need a strong assumption to support receipt-freeness.But voters should used ELGamal cryptosystem to create their key-pairs.Finally, we evaluate the performance of TAEV on a PC with2.0GHZ CPU and1GB memory by implementing a simple program. We use5key escrow centers,7talliers and8copies for cut-and-choose, and it cost2224ms and9716ms forcomputation in registration phase and vote phase. The communication cost of thesetwo phases is59556byte and51631byte. Comparing with the cost of registrationphase and vote phase, the cost of tally phase can be ignored. We also evaluate theperformance of the PEQDL-based registration sub-protocol and it is shows that the registration phase cost3854ms for computation and74976byte for communication.With the increase of key escrow centers, talliers and copies for cut-and-choose, thecost has a linear growth.TAEV has the following characteristics. First, it is flexible that participants canchoose any kind of cryptosystem to create key pairs and encrypt communication data.Second, there isn’t any authority need to be highly trusted. Third, a certain number offaulty participants can be tolerated and can be traced if necessary. Last, TAEV protectanonymity in the registration phase, so that it can reduce the computational load ofthe vote phase.