761 Key Concepts and Protocols in E-Voting Rui F. L. Joaquim CCISEL, Portugal K IntroductIon With today's technology, it is possible to improve the decision support of our networked and virtual organi- zations. More specific we are talking about e-voting systems, namely Internet voting systems, which are a convenient way to express actors' will and/or opinion with all properties of traditional voting, such as: ac- curacy, democracy, privacy, and verifiability. To look at e-voting systems only as a modern way to conduct political or private organizations' elections is diminutive of its potential. Whenever people's pri- vacy is at stake e-voting expertise can come in hand. Examples of such scenarios are quality surveys to improve service quality, for instance banks and other private or public service entities; health related surveys, for instance sexual behavior survey to help in the cre- ation of a plan to fight sexual transmitted diseases, and teaching quality surveys to help adapt classes' content to students' needs. Currently, commercially-available e-voting solu- tions are mainly "black box software." Most sellers hide the problems of deploying an e-voting applica- tion just for the profit. It is necessary to be aware of the risks, difficulties, and problems raised by e-voting systems, as well as the current solutions. Only well- informed actors, who know the risks and guaranties of e-voting systems, can consciously decide on the use of e-voting systems to improve networked and virtual organizations. After all, we are talking about protecting our own privacy. The main problems we face when designing an e- voting system occur exactly when we try to conciliate all voting properties, namely when we try to conciliate privacy with the other properties, for example how to conciliate privacy with verifiability. As a result of research in the field for the last 25 years, advanced cryptographic techniques such as blind signatures, mix-nets, and homomorphic ciphers were used to tackle such problems. e-VotIng propertIes Before starting our discussion on e-voting it is useful to define the core properties of any voting system. · Accuracy: A voting system is accurate if (1) it is not possible to alter a vote, (2) it is not possible to eliminate a valid vote from the final tally, and (3) it is not possible to include an invalid vote in the final tally. Democracy: A voting system is democratic if (1) it only allows eligible voters to vote, (2) it ensures that eligible voters vote only once, and (3) ensures the equality of knowledge, that is no partial results. Privacy: A voting system has the privacy property if (1) neither the voting authorities nor anyone else can link any ballot to the voter who cast it, and (2) no voter can prove that she voted in a particular way. An e-voting system that holds the condition (2) is also called receipt-free. Verifiability: A voting system is verifiable if it provides mechanisms to verify the correctness of the final tally. · · · tHe rIsks oF e-VotIng E-voting systems, namely Internet voting systems, still face several problems that prevent their widespread use today (California, 2000; Caltech-MIT, 2001; Cranor, 2001; Rivest, 2001; Rubin, 2002; Internet Policy In- stitute, 2001). The problems can be broadly divided in three main classes. The first class includes security and fault tolerance problems inherited from the current Internet architec- ture. Vital services, such as DNS name resolution, can be tampered in order to mislead users into spoofing servers (Lioy, Maino, Marian, & Mazzocchi, 2000). IP routing mechanisms and protocols, managed by many different organizations, should deal with partial Copyright © 2008, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited.