Results 1-20 of 29.
((uid:50009016))

Bookmark and Share    
Full Text
Peer Reviewed
See detailShort paper: Mechanized Proofs of Verifiability and Privacy in a paper-based e-voting Scheme
Zollinger, Marie-Laure UL; Roenne, Peter UL; Ryan, Peter UL

in International Conference on Financial Crypto Workshop on Advances in Secure Electronic Voting (2020, February)

Detailed reference viewed: 23 (0 UL)
Full Text
Peer Reviewed
See detailCoercion-Resistant Voting in Linear Time via Fully Homomorphic Encryption: Towards a Quantum-Safe Scheme
Roenne, Peter UL; Atashpendar, Arash UL; Kristian, Gjøsteen et al

in Financial Cryptography and Data Security 2019. FC 2019: International Workshops, CIW, VOTING, and WTSC (2020)

We present an approach for performing the tallying work in the coercion-resistant JCJ voting protocol, introduced by Juels, Catalano, and Jakobsson, in linear time using fully homomorphic encryption (FHE ... [more ▼]

We present an approach for performing the tallying work in the coercion-resistant JCJ voting protocol, introduced by Juels, Catalano, and Jakobsson, in linear time using fully homomorphic encryption (FHE). The suggested enhancement also paves the path towards making JCJ quantum-resistant, while leaving the underlying structure of JCJ intact. The pairwise comparison-based approach of JCJ using plaintext equivalence tests leads to a quadratic blow-up in the number of votes, which makes the tallying process rather impractical in realistic settings with a large number of voters. We show how the removal of invalid votes can be done in linear time via a solution based on recent advances in various FHE primitives such as hashing, zero-knowledge proofs of correct decryption, verifiable shuffles and threshold FHE. We conclude by touching upon some of the advantages and challenges of such an approach, followed by a discussion of further security and post-quantum considerations. [less ▲]

Detailed reference viewed: 279 (76 UL)
Full Text
See detailAuthenticated Key Distribution: When the Coupon Collector is Your Enemy
Beunardeau, Marc; El Orche, Fatima Ezzahra UL; Maimut, Diana et al

in Innovative Security Solutions for Information Technology and Communications (2019, November 14)

We introduce new authenticated key exchange protocols which on the one hand do not resort to standard public key setups with corresponding assumptions of computationally hard problems, but on the other ... [more ▼]

We introduce new authenticated key exchange protocols which on the one hand do not resort to standard public key setups with corresponding assumptions of computationally hard problems, but on the other hand, are more efficient than distributing symmetric keys among the participants. To this end, we rely on a trusted central authority distributing key material whose size is independent of the total number of users, and which allows the users to obtain shared secret keys. We analyze the security of our construction, taking into account various attack models. Importantly, only symmetric primitives are needed in the protocol making it an alternative to quantum-safe key exchange protocols which rely on hardness assumptions. [less ▲]

Detailed reference viewed: 10 (2 UL)
Full Text
Peer Reviewed
See detailUser Experience Design for E-Voting: How mental models align with security mechanisms
Zollinger, Marie-Laure UL; Distler, Verena UL; Roenne, Peter UL et al

in Electronic Voting (2019, October)

This paper presents a mobile application for vote-casting and vote-verification based on the Selene e-voting protocol and explains how it was developed and implemented using the User Experience Design ... [more ▼]

This paper presents a mobile application for vote-casting and vote-verification based on the Selene e-voting protocol and explains how it was developed and implemented using the User Experience Design process. The resulting interface was tested with 38 participants, and user experience data was collected via questionnaires and semi-structured interviews on user experience and perceived security. Results concerning the impact of displaying security mechanisms on UX were presented in a complementary paper. Here we expand on this analysis by studying the mental models revealed during the interviews and compare them with theoretical security notions. Finally, we propose a list of improvements for designs of future voting protocols. [less ▲]

Detailed reference viewed: 109 (7 UL)
Full Text
Peer Reviewed
See detailA Lightweight Implementation of NTRUEncrypt for 8-bit AVR Microcontrollers
Cheng, Hao UL; Groszschädl, Johann UL; Roenne, Peter UL et al

Scientific Conference (2019, August)

Introduced in 1996, NTRUEncrypt is not only one of the earliest but also one of the most scrutinized lattice-based cryptosystems and a serious contender in NIST’s ongoing Post-Quantum Cryptography (PQC ... [more ▼]

Introduced in 1996, NTRUEncrypt is not only one of the earliest but also one of the most scrutinized lattice-based cryptosystems and a serious contender in NIST’s ongoing Post-Quantum Cryptography (PQC) standardization project. An important criterion for the assessment of candidates is their computational cost in various hardware and software environments. This paper contributes to the evaluation of NTRUEncrypt on the ATmega class of AVR microcontrollers, which belongs to the most popular 8-bit platforms in the embedded domain. More concretely, we present AvrNtru, a carefully-optimized implementation of NTRUEncrypt that we developed from scratch with the goal of achieving high performance and resistance to timing attacks. AvrNtru complies with version 3.3 of the EESS#1 specification and supports recent product-form parameter sets like ees443ep1, ees587ep1, and ees743ep1. A full encryption operation (including mask generation and blinding- polynomial generation) using the ees443ep1 parameters takes 834,272 clock cycles on an ATmega1281 microcontroller; the decryption is slightly more costly and has an execution time of 1,061,683 cycles. When choosing the ees743ep1 parameters to achieve a 256-bit security level, 1,539,829 clock cycles are cost for encryption and 2,103,228 clock cycles for decryption. We achieved these results thanks to a novel hybrid technique for multiplication in truncated polynomial rings where one of the operands is a sparse ternary polynomial in product form. Our hybrid technique is inspired by Gura et al’s hybrid method for multiple-precision integer multiplication (CHES 2004) and takes advantage of the large register file of the AVR architecture to minimize the number of load instructions. A constant-time multiplication in the ring specified by the ees443ep1 parameters requires only 210,827 cycles, which sets a new speed record for the arithmetic component of a lattice-based cryptosystem on an 8-bit microcontroller. [less ▲]

Detailed reference viewed: 29 (1 UL)
Full Text
Peer Reviewed
See detailSecurity – Visible, Yet Unseen? How Displaying Security Mechanisms Impacts User Experience and Perceived Security
Distler, Verena UL; Zollinger, Marie-Laure UL; Lallemand, Carine UL et al

in Proceedings of ACM CHI Conference on Human Factors in Computing Systems (CHI2019) (2019, April)

An unsolved debate in the field of usable security concerns whether security mechanisms should be visible, or blackboxed away from the user for the sake of usability. However, tying this question to ... [more ▼]

An unsolved debate in the field of usable security concerns whether security mechanisms should be visible, or blackboxed away from the user for the sake of usability. However, tying this question to pragmatic usability factors only might be simplistic. This study aims at researching the impact of displaying security mechanisms on user experience (UX) in the context of e-voting. Two versions of an e-voting application were designed and tested using a between-group experimental protocol (N=38). Version D displayed security mechanisms, while version ND did not reveal any security-related information. We collected data on UX using standardised evaluation scales and semi-structured interviews. Version D performed better overall in terms of UX and need fulfilment. Qualitative analysis of the interviews gives further insights into factors impacting perceived security. Our study adds to existing research suggesting a conceptual shift from usability to UX and discusses implications for designing and evaluating secure systems. [less ▲]

Detailed reference viewed: 373 (47 UL)
Full Text
Peer Reviewed
See detailRisk-Limiting Tallies
Jamroga, Wojciech UL; Roenne, Peter UL; Ryan, Peter UL et al

in Electronic Voting: Proceedings of E-Vote-ID (2019)

Detailed reference viewed: 5 (1 UL)
Full Text
Peer Reviewed
See detailHoneyPAKEs
Lopez Becerra, José Miguel UL; Roenne, Peter UL; Ryan, Peter UL et al

in Security Protocols XXVI: Lecture Notes in Computer Science (2018, November 27)

We combine two security mechanisms: using a Password-based Authenticated Key Establishment (PAKE) protocol to protect the password for access control and the Honeywords construction of Juels and Rivest to ... [more ▼]

We combine two security mechanisms: using a Password-based Authenticated Key Establishment (PAKE) protocol to protect the password for access control and the Honeywords construction of Juels and Rivest to detect loss of password files. The resulting construction combines the properties of both mechanisms: ensuring that the password is intrinsically protected by the PAKE protocol during transmission and the Honeywords mechanisms for detecting attempts to exploit a compromised password file. Our constructions lead very naturally to two factor type protocols. An enhanced version of our protocol further provides protection against a compromised login server by ensuring that it does not learn the index to the true password. [less ▲]

Detailed reference viewed: 69 (10 UL)
Full Text
Peer Reviewed
See detailRevisiting Deniability in Quantum Key Exchange via Covert Communication and Entanglement Distillation
Atashpendar, Arash UL; Policharla, Guru Vamsi; Roenne, Peter UL et al

in Secure IT Systems, 23rd Nordic Conference, NordSec 2018. Lecture Notes in Computer Science, vol 11252. Springer, Cham (2018, November 02)

We revisit the notion of deniability in quantum key exchange (QKE), a topic that remains largely unexplored. In the only work on this subject by Donald Beaver, it is argued that QKE is not necessarily ... [more ▼]

We revisit the notion of deniability in quantum key exchange (QKE), a topic that remains largely unexplored. In the only work on this subject by Donald Beaver, it is argued that QKE is not necessarily deniable due to an eavesdropping attack that limits key equivocation. We provide more insight into the nature of this attack and how it extends to other constructions such as QKE obtained from uncloneable encryption. We then adopt the framework for quantum authenticated key exchange, developed by Mosca et al., and extend it to introduce the notion of coercer-deniable QKE, formalized in terms of the indistinguishability of real and fake coercer views. Next, we apply results from a recent work by Arrazola and Scarani on covert quantum communication to establish a connection between covert QKE and deniability. We propose DC-QKE, a simple deniable covert QKE protocol, and prove its deniability via a reduction to the security of covert QKE. Finally, we consider how entanglement distillation can be used to enable information-theoretically deniable protocols for QKE and tasks beyond key exchange. [less ▲]

Detailed reference viewed: 197 (56 UL)
Full Text
Peer Reviewed
See detailElectryo, In-person Voting with Transparent Voter Verifiability and Eligibility Verifiability
Roenne, Peter UL; Ryan, Peter UL; Zollinger, Marie-Laure UL

E-print/Working paper (2018)

Selene is an e-voting protocol that allows voters to directly check their individual vote, in cleartext, in the final tally via a tracker system, while providing good coercion mitigation. This is in ... [more ▼]

Selene is an e-voting protocol that allows voters to directly check their individual vote, in cleartext, in the final tally via a tracker system, while providing good coercion mitigation. This is in contrast to conventional, end-to-end verifiable schemes in which the voter verifies the presence of an encryption of her vote on the bulletin board. The Selene mechanism can be applied to many e-voting schemes, but here we present an application to the polling station context, resulting in a voter-verifiable electronic tally with a paper audit trail. The system uses a smartcard-based public key system to provide the individual verifica- tion and universal eligibility verifiability. The paper record contains an encrypted link to the voter’s identity, requiring stronger assumptions on ballot privacy than normal paper voting, but with the benefit of pro- viding good auditability and dispute resolution as well as supporting (comparison) risk limiting audits. [less ▲]

Detailed reference viewed: 114 (10 UL)
Full Text
Peer Reviewed
See detailCholesteric Liquid Crystal Shells as Enabling Material for Information-Rich Design and Architecture.
Schwartz, Mathew; Lenzini, Gabriele UL; Geng, Yong UL et al

in Advanced Materials (2018)

The responsive and dynamic character of liquid crystals (LCs), arising from their ability to self-organize into long-range ordered structures while maintaining fluidity, has given them a role as key ... [more ▼]

The responsive and dynamic character of liquid crystals (LCs), arising from their ability to self-organize into long-range ordered structures while maintaining fluidity, has given them a role as key enabling materials in the information technology that surrounds us today. Ongoing research hints at future LC-based technologies of entirely different types, for instance by taking advantage of the peculiar behavior of cholesteric liquid crystals (CLCs) subject to curvature. Spherical shells of CLC reflect light omnidirectionally with specific polarization and wavelength, tunable from the UV to the infrared (IR) range, with complex patterns arising when many of them are brought together. Here, these properties are analyzed and explained, and future application opportunities from an inter- disciplinary standpoint are discussed. By incorporating arrangements of CLC shells in smart facades or vehicle coatings, or in objects of high value subject to counterfeiting, game-changing future uses might arise in fields spanning infor- mation security, design, and architecture. The focus here is on the challenges of a digitized and information-rich future society where humans increasingly rely on technology and share their space with autonomous vehicles, drones, and robots. [less ▲]

Detailed reference viewed: 243 (8 UL)
Full Text
Peer Reviewed
See detailSecurity in the Shell : An Optical Physical Unclonable Function made of Shells of Cholesteric Liquid Crystals
Lenzini, Gabriele UL; Samir, Ouchani; Roenne, Peter UL et al

in Proc. of the 9th IEEE Workshop on Information Forensics and Security (2017, October 02)

We describe the application in security of shells of Cholesteric Liquid Crystals (ChLCs). Such shells have a diameter in the microns range and can be gathered in hundreds in a surface area as small as a ... [more ▼]

We describe the application in security of shells of Cholesteric Liquid Crystals (ChLCs). Such shells have a diameter in the microns range and can be gathered in hundreds in a surface area as small as a nail’s head. Because of their structural properties, a bundle of them reflects light, creating colorful patterns that we argue to be unique and computationally hard to predict. We argue also that the bundle itself is unclonable. These are typical properties of Physically Unclonable Functions, a family to which shells of ChLCs belong too. Herein we discuss their physical and security properties and their potential use in object authentication. [less ▲]

Detailed reference viewed: 301 (41 UL)
Peer Reviewed
See detailDeniability in Quantum Cryptography
Atashpendar, Arash UL; Roenne, Peter UL; Ostrev, Dimiter UL et al

Poster (2017, June 14)

This poster describes ongoing work on deniability in quantum cryptography, an area of research that remains almost entirely unexplored in the quantum information processing literature. Deniability is a ... [more ▼]

This poster describes ongoing work on deniability in quantum cryptography, an area of research that remains almost entirely unexplored in the quantum information processing literature. Deniability is a well-known and fundamental concept in classical cryptography and it can be defined as the ability for the sender of a message to deny the contents of a message or the very act of having participated in an exchange, e.g. having sent the said message. We discuss deniability in the context of quantum key exchange and address a particular problem, first discovered by Donald Beaver, where he claims that all QKD protocols are undeniable. The claim is that while we do get a one-time pad (OTP) using QKD, it does not provide the property of key equivocation as it is expected in the Shannon sense for a OTP. Intuitively, this difficulty lies in the quantum channel alone and it has to do with the fact that in QKD, while we generate entropy by expanding an initially short pre-shared key into an arbitrary longer secret key, we do so by exchanging information over a quantum as well as a classical channel, which could potentially leave a binding transcript of Alice's decisions to the final secret key. This is in contrast with the implicit assumption that Eve knows nothing about how two given parties have established their shared OTP in the first place. We discuss the importance of deniability in cryptography and its wide range of applications, along with cryptographic primitives other than key exchange where deniability might be a desired property. Finally, we present a series of fundamental open questions in this area of research and discuss quantum cryptographic primitives that lend themselves to devising deniable protocols. [less ▲]

Detailed reference viewed: 251 (24 UL)
Full Text
Peer Reviewed
See detailUsing Selene to Verify your Vote in JCJ
Iovino, Vincenzo UL; Rial, Alfredo UL; Roenne, Peter UL et al

in Workshop on Advances in Secure Electronic Voting (VOTING'17) (2017, April 07)

Detailed reference viewed: 233 (29 UL)
Full Text
Peer Reviewed
See detailIs a visuo-haptic differentiation of zebra mussel and quagga mussel based on a single external morphometric shell character possible?
Teubner, Diana; Wesslein, Ann-Katrin; Roenne, Peter UL et al

in Aquatic Invasions (2016)

Detailed reference viewed: 144 (2 UL)
Full Text
Peer Reviewed
See detailJCJ with Improved Verifiability Guarantees
Roenne, Peter UL

Scientific Conference (2016)

Detailed reference viewed: 99 (5 UL)
Full Text
Peer Reviewed
See detailCorrespondences between WZNW models and CFTs with W-algebra symmetry
Creutzig, Thomas; Hikida, Yasuaki; Roenne, Peter UL

in JHEP (2016), 02

Detailed reference viewed: 108 (5 UL)
See detail(Universal) Unconditional Verifiability in E-Voting without Trusted Parties
Gallegos-Garcia, Gina; Iovino, Vincenzo UL; Roenne, Peter UL et al

E-print/Working paper (2016)

Detailed reference viewed: 94 (4 UL)
Full Text
Peer Reviewed
See detailMarginal deformations and the Higgs phenomenon in higher spin AdS3 holography
Hikida, Yasuaki; Roenne, Peter Browne UL

in Journal of High Energy Physics [=JHEP] (2015), 7

Detailed reference viewed: 96 (15 UL)
Full Text
Peer Reviewed
See detailSelene: Voting with Transparent Verifiability and Coercion-Mitigation
Ryan, Peter UL; Roenne, Peter UL; Iovino, Vincenzo UL

in Abstract book of 1st Workshop on Advances in Secure Electronic Voting (2016), 2015

Detailed reference viewed: 389 (42 UL)