Quantum protocols for anonymous voting and surveying

We describe quantum protocols for voting and surveying. A key feature of our schemes is the use of entangled states to ensure that the votes are anonymous and to allow the votes to be tallied. The entanglement is distributed over separated sites; the physical inaccessibility of any one site is sufficient to guarantee the anonymity of the votes. The security of these protocols with respect to various kinds of attack is discussed. We also discuss classical schemes and show that our quantum voting protocol represents a N-fold reduction in computational complexity, where N is the number of voters.Comment: 8 pages. V2 includes the modifications made for the published versio

A Novel Blind Signature Scheme Based On Discrete Logarithm Problem With Un-traceability

Blind Signatures are a special type of digital signatures which possess two special properties of blindness and untraceability, which are important for today’s real world applications that require authentication , integrity , security , anonymity and privacy. David Chaum[2] was the first to propose the concept of blind signatures. The scheme's security was based on the difficulty of solving the factoring problem [3, 4]. Two properties that are important for a blind signature scheme in order to be used in various modern applications are blindness and untraceability[2, 5, 6] . Blindness means that the signer is not able to know the contents of the message while signing it, which is achieved by disguising (or blinding) the message through various methods. Untraceability refers to preventing the signer from linking the blinded message it signs to a later unblinded version that it may be called upon to verify. Blind signatures based on discrete logarithm problem are still an area with much scope for research. We aim to propose a novel blind signature scheme with untraceability , based on the discrete logarithm problem

A novel blind signature scheme and its variations based on DLP

Blind Signature is an addendum of Digital Signature.It is a two party protocol,in which a requester sends a message to a signer to get the signature without revealing the contents of the message to the signer. The signer puts the signature using his/her private keys and the generated signature can be verified by anyone using signer’s public keys.Blind signature has a major property called as untraceability or unlinkability i.e after the generation of the signature the signer cannot link the message-signature pair. This is known as blindness property. We have proposed blind signature scheme and its variation based on discrete logarithm problem(DLP),in which major emphasis is given on the untraceability property. We have cryptanalyzed Carmenisch et al.’s blind signature scheme and Lee et al.’s blind signature scheme and proposed an improvement over it. It is found that, the proposed scheme has less computational complexity and they can withstand active attacks. Blind signature has wide applications in real life scenarios, such as, e-cash, e-voting and e-commerece applications. i

Dining Cryptographers are Practical

The dining cryptographers protocol provides information-theoretically secure sender and recipient untraceability. However, the protocol is considered to be impractical because a malicious participant may disrupt the communication. We propose an implementation which provides information-theoretical security for senders and recipients, and in which a disruptor with limited computational capabilities can easily be detected.Comment: 12 page

I2PA : An Efficient ABC for IoT

Internet of Things (IoT) is very attractive because of its promises. However, it brings many challenges, mainly issues about privacy preserving and lightweight cryptography. Many schemes have been designed so far but none of them simultaneously takes into account these aspects. In this paper, we propose an efficient ABC scheme for IoT devices. We use ECC without pairing, blind signing and zero knowledge proof. Our scheme supports block signing, selective disclosure and randomization. It provides data minimization and transactions' unlinkability. Our construction is efficient since smaller key size can be used and computing time can be reduced. As a result, it is a suitable solution for IoT devices characterized by three major constraints namely low energy power, small storage capacity and low computing power

A Light-Weight Group Signature Scheme for Wireless Networks Based-on BBS Short Group Signature

In the natural context of wireless network environment, the communications between wireless nodes are more easily observed for the goal of the network traffic analysis. Thus, to enable a secure and anonymous communication system from thwarting of such analysis attacks would be strongly desirable. In this paper, we propose a secure and anonymous communication system using pairing-based group signatures. The achievement of secure and anonymous communication is performed by allowing all valid member wireless nodes of a particular privilege group to authenticate each other without revealing their own identitie

Authentication Scheme for Flexible Charging and Discharging of Mobile Vehicles in the V2G Networks

Navigating security and privacy challenges is one of the crucial requirements in the vehicle-to-grid (V2G) network. Since electric vehicles (EVs) need to provide their private information to aggregators/servers when charging/discharging at different charging stations, privacy of the vehicle owners can be compromised if the information is misused, traced, or revealed. In a wide V2G network, where vehicles can move outside of their home network to visiting networks, security and privacy become even more challenging due to untrusted entities in the visiting networks. Although some privacy-preserving solutions were proposed in the literature to tackle this problem, they do not protect against well-known security attacks and generate a huge overhead. Therefore, we propose a mutual authentication scheme to preserve privacy of the EV's information from aggregators/servers in the home as well as distributed visiting V2G networks. Our scheme, based on a bilinear pairing technique with an accumulator performing batch verification, yields higher system efficiency, defeats various security attacks, and maintains untraceability, forward privacy, and identity anonymity. A performance analysis shows that our scheme, in comparison with the existing solutions, significantly generates lower communication and computation overheads in the home and centralized V2G networks, and comparable overheads in the distributed visiting V2G networks

Performance and Security of Group Signature in Wireless Networks

A Group signature protocol is a cryptographic scheme that decouples a user identity and location from verification procedure during authentication. In a group signature scheme, a user is allowed to generate signatures on behalf of other group members but identity and location information of the signer is not known by a verifier. This ensures privacy, authentication and unlinkability of users. Although group signature is expensive to implement, its existential anonymity, non-repudiation and untraceablility properties make it attractive especially for resources-constrained devices in wireless network. A general group signature scheme usually contains six basic phases: setup (or key generation), join, message signing (or signature generation), signature verification, open and user revocation. In this paper, an evaluation of the performance of group signature based on three of the phases mentioned above is considered and its security in wireless networks examined. The key generation, signing and verification algorithms are implemented in Java 8. A proof of security of group signature by implication is also presented