Deniable Encryption in Replacement of Untappable Channel to Prevent Coercion
The incoerciblety to prevent rigging in e-voting and e-auction have been studied in different literatures. It is realized that the notion of a virtual booth and untappable channel are required to prevent coerciveness. Virtual booth protects the candidates to cast their private values without being observed by the adversary/coercer. However the adversary can influence the candidates after their casting. Adversary used to acquire the encrypted votes/bids either from the colluded authorities (voting server, auctioneer) or by eavesdropping the communicating channel. The adversary then coerces the candidates to disclose their private values with their private keys and verifies whether the ciphers are the encryption of the private values. In the prior literatures of e-voting and e-auctioning, threshold-encryption and receipt-free mechanism are used to prevent the coercion and collusion respectively. But they assumed untappable channel to restrict eavesdropping. However, untappable channel is difficult to achieve. It should be a dedicated trusted link or continuous fiber link to implement untappable channel. In this paper we present an alternative of untappable channel using deniable encryption. Deniable encryption does not restrict the adversary to eavesdrop, but if the candidates are coerced, they are able to find a different value vf and can convince the adversary that the ciphers are the encryption of vf, without reveling the true private value vr. Therefore, eavesdropping does not help the coercer, as he may be plausible denied by the candidates. Our scheme is based on public key probabilistic encryption mechanism. We assume that the sender side (candidate) coercion is only possible, that is, the coercer can not coerce the receivers (authorities).
Unable to display preview. Download preview PDF.
- 1.Benaloh, J., Tuinstra, D.: Receipt-Free Secter-Ballot Election (Extended Abstract). In: Proc. 26th ACM Symposium on the Theory of Computing (STOC), pp. 544–553. ACM, New York (1994)Google Scholar
- 8.Baudron, O., Fouque, P.-A., Pointcheval, D., Stern, J., Poupard, G.: Practical Multi-Candidate Election System. In: Proc. PODC 2001, 20th Annual ACM Symposium on Principles of Distributed Computing, pp. 274–283. ACM, New York (2001)Google Scholar
- 9.Yvo, D.: Threshold Cryptography. Trans. on European Transaction on Telecommunications 5(4), 449–457Google Scholar
- 16.Howlader, J., Ghosh, A., Roy, T.D.: Secure Receipt-Free Sealed-Bid Electronic Auction. In: Proc. IC3 2009. CCIS, vol. 40. Springer, Heidelberg (2009)Google Scholar
- 20.Magkos, E., Burmester, M., Chrissikopoulos, V.: Receipt-Freeness in Large-Scale Elections without Untappable Channels. In: Proc. 1st IFIP Conference on E-Commerce, E-Business, E-Government 2001, IFIP Conference Proceedings, vol. 202, pp. 683–694 (2001)Google Scholar
- 22.Howlader, J., Basu, S.: Sender-Side Public Key Deniable Encryption Scheme. In: Proc. ARTCom 2009, pp. 9–13. IEEE, Los Alamitos (2009)Google Scholar