Although fair exchange protocols are being widely implemented, there are few formal methods able to verify them. This work introduces the strand spaces method for verifying certified mail delivery protocols, a subclass of fair exchange protocols. Three fair exchange properties are verified: effectiveness, verifiability of TTP and timeliness. For effectiveness and verifiability we used the FPH p...

The Prêt à Voter end-to-end verifiable voting system makes use of receipts, retained by voters, to provide individual verifiability that their vote has been recorded as cast. The paper discusses issues around the production and acceptance of receipts, and presents an alternative approach to individual verifiability based on Authentication Codes. These codes are constructed, in the encrypted dom...

We describe information security requirements for a secure and functional Internet voting scheme. Then we present the voting scheme with multiple parties; this voting scheme satisfies all these security requirements. In this scheme, the voter gets a signed key from the registrar, where the registrar signs the key as blinded. The voter uses this signed key during the voting period. All other par...

The term “end-to-end verifiability” has been used over the past several years to describe multiple voting system proposals. The term has, however, never been formally defined. As a result, its meaning tends to change from voting system to voting system. We propose a definition for end-to-end verifiability of public elections based on performance requirements, as opposed to design requirements. ...

The recently proposed Prêt à Voter election scheme uses decryption mixes to achieve anonymity of votes and verifiability of an election while requiring minimal trust in the component of the election system that performs these mixes. However, this scheme still requires trust in several human and machine components; these requirements make the scheme impractical for use in remote voting. To adapt...

Verifiability is an important component of elections. It is related to aspects like trust in the correctness of the election results, transparency of the election processes, and preparation for a possible contestation of the election. In particular the last aspect is of crucial importance in legally regulated elections. Verifiability in this context means that voting systems must be designed co...

Executive Summary and Recommendations This submission addresses two issues related to e-voting in Victoria: i. Problems with the underlying design of the scaled-down prototype of the vVote e-voting system used in the 2014 Victorian State Election make it unsuitable for larger-scale general use in future elections. ii. Lessons learned from the 2014 vVote trial and from similar trials internation...