Introducing Verifiability in the POLYAS Remote Electronic Voting System

Remote electronic voting continues to attract attention. A greater number of election officials are opting to enable a remote electronic voting channel. More and more scientific papers have been published introducing or improving existing remote electronic voting protocols. However, while the scientific papers focus on different aspects of verifiability, most of the systems in use do not provide verifiability. This gap is closed in this paper by extending a widely used remote electronic voting system, the POLYAS system, to provide verifiability. This approach has been tested in the 2010 election of the German Society for Computer Scientists and will be applied in future elections

Partial Verifiability in POLYAS for the GI Elections

We discuss the use of POLYAS, an Internet voting system, in GI elections before 2010, in 2010 and 2011, as well as in future. We briefly describe how the system was extended in 2010 to provide partial verifiability and how the integrity of the GI election result was verified in the 2010 and 2011 elections. Information necessary for partial verifiability has so far only been made available to a small group of researchers. In future it would be ideal to make this, and more information, available to the general public, or to GI members, in order to increase the level of verifiability. We highlight legal considerations accompanying these possibilities, including publishing more details about the election results, the requirement for secret elections and avoiding vote buying, and how to handle complaints. Motivated by legal constraints, we propose further improvements to the POLYAS system. Finally, we generalize our findings to any partially verifiable Internet voting system

Evaluation and Improvement of Internet Voting Schemes Based on Legally-Founded Security Requirements

In recent years, several nations and private associations have introduced Internet voting as additional means to conduct elections. To date, a variety of voting schemes to conduct Internet-based elections have been constructed, both from the scientific community and industry. Because of its fundamental importance to democratic societies, Internet voting – as any other voting method – is bound to high legal standards, particularly imposing security requirements on the voting method. However, these legal standards, and resultant derived security requirements, partially oppose each other. As a consequence, Internet voting schemes cannot enforce these legally-founded security requirements to their full extent, but rather build upon specific assumptions. The criticality of these assumptions depends on the target election setting, particularly the adversary expected within that setting. Given the lack of an election-specific evaluation framework for these assumptions, or more generally Internet voting schemes, the adequacy of Internet voting schemes for specific elections cannot readily be determined. Hence, selecting the Internet voting scheme that satisfies legally-founded security requirements within a specific election setting in the most appropriate manner, is a challenging task. To support election officials in the selection process, the first goal of this dissertation is the construction of a evaluation framework for Internet voting schemes based on legally-founded security requirements. Therefore, on the foundation of previous interdisciplinary research, legally-founded security requirements for Internet voting schemes are derived. To provide election officials with improved decision alternatives, the second goal of this dissertation is the improvement of two established Internet voting schemes with regard to legally-founded security requirements, namely the Polyas Internet voting scheme and the Estonian Internet voting scheme. Our research results in five (partially opposing) security requirements for Internet voting schemes. On the basis of these security requirements, we construct a capability-based risk assessment approach for the security evaluation of Internet voting schemes in specific election settings. The evaluation of the Polyas scheme reveals the fact that compromised voting devices can alter votes undetectably. Considering surrounding circumstances, we eliminate this shortcoming by incorporating out of band codes to acknowledge voters’ votes. It turns out that in the Estonian scheme, four out of five security requirements rely on the correct behaviour of voting devices. We improve the Estonian scheme in that regard by incorporating out of band voting and acknowledgment codes. Thereby, we maintain four out of five security requirements against adversaries capable of compromising voting devices

Cast-as-Intended Mechanism with Return Codes Based on PETs

We propose a method providing cast-as-intended verifiability for remote electronic voting. The method is based on plaintext equivalence tests (PETs), used to match the cast ballots against the pre-generated encrypted code tables. Our solution provides an attractive balance of security and functional properties. It is based on well-known cryptographic building blocks and relies on standard cryptographic assumptions, which allows for relatively simple security analysis. Our scheme is designed with a built-in fine-grained distributed trust mechanism based on threshold decryption. It, finally, imposes only very little additional computational burden on the voting platform, which is especially important when voters use devices of restricted computational power such as mobile phones. At the same time, the computational cost on the server side is very reasonable and scales well with the increasing ballot size

ANALISA FAKTOR COMPATIBILITY TERHADAP IMPLEMENTASI E-VOTING

sebuah peralihan proses pemilihan yang bersifat manual kepada bentuk yang terkomputerisasi. Berdasarkan penelitian yang dilakukan oleh rahmad, Compatibility memberikan pengaruh sebesar 80% terhadap minat seseorang dalam menggunakan e-voting (intention to use). Penelitian ini merupakan pengembangan dari penelitian rahmad, dengan melakukan analisa terhadap keterkaitan faktor compatibility dengan implementasi e-voting.Kaitan faktor compatibility terhadap implementasi e-voting dibagi menjadi tiga kelompok yaitu infrastructure & equipment, e-voting technology dan implementation

Formal Treatment of Distributed Trust in Electronic Voting

Electronic voting systems are among the most security critical distributed systems. Different trust concepts are implemented to mitigate the risk of conspiracies endangering security properties. These concepts render systems often very complex and end users no longer recognize whom they need to trust. Correspondingly, specific trust considerations are necessary to support users. Recently, resilience terms have been proposed in order to express, which entities can violate the addressed security properties in particular by illegal collaborations. However, previous works derived these resilience terms manually. Thus, successful attacks can be missed. Based on this approach, we propose a framework to formally and automatically derive these terms. Our framework comprises a knowledge calculus, which allows us to model knowledge and reason about knowledge of collaborating election entities. The introduced framework is applied to deduce previously manually derived resilience terms of three remote electronic voting systems, namely Polyas, Helios and the Estonian voting system. Thereby, we were able to discover mistakes in previous derivations

A Protocol for Cast-as-Intended Verifiability with a Second Device

Numerous institutions, such as companies, universities, or non-governmental organizations, employ Internet voting for remote elections. Since the main purpose of an election is to determine the voters' will, it is fundamentally important to ensure that the final election result correctly reflects the voters' votes. To this end, modern secure Internet voting schemes aim for what is called end-to-end verifiability. This fundamental security property ensures that the correctness of the final result can be verified, even if some of the computers or parties involved are malfunctioning or corrupted. A standard component in this approach is so called cast-as-intended verifiability which enables individual voters to verify that the ballots cast on their behalf contain their intended choices. Numerous approaches for cast-as-intended verifiability have been proposed in the literature, some of which have also been employed in real-life Internet elections. One of the well established approaches for cast-as-intended verifiability is to employ a second device which can be used by voters to audit their submitted ballots. This approach offers several advantages - including support for flexible ballot/election types and intuitive user experience - and it has been used in real-life elections, for instance in Estonia. In this work, we improve the existing solutions for cast-as-intended verifiability based on the use of a second device. We propose a solution which, while preserving the advantageous practical properties sketched above, provides tighter security guarantees. Our method does not increase the risk of vote-selling when compared to the underlying voting protocol being augmented and, to achieve this, it requires only comparatively weak trust assumptions. It can be combined with various voting protocols, including commitment-based systems offering everlasting privacy

Matters of Coercion-Resistance in Cryptographic Voting Schemes

This work addresses coercion-resistance in cryptographic voting schemes. It focuses on three particularly challenging cases: write-in candidates, internet elections and delegated voting. Furthermore, this work presents a taxonomy for analyzing and comparing a huge variety of voting schemes, and presents practical experiences with the voting scheme Bingo Voting

sElect: A Lightweight Verifiable Remote Voting System

Modern remote electronic voting systems, such as the prominent Helios system, are designed to provide vote privacy and verifiability, where, roughly speaking, the latter means that voters can make sure that their votes were actually counted. In this paper, we propose a new practical voting system called sElect (secure/simple elections). This system, which we implemented as a platform independent web-based application, is meant for low-risk elections and is designed to be particularly simple and lightweight in terms of its structure, the cryptography it uses, and the user experience. One of the unique features of sElect is that it supports fully automated verification, which does not require any user interaction and is triggered as soon as a voter looks at the election result. Despite its simplicity, we prove that this system provides a good level of privacy, verifiability, and accountability for low-risk elections