Deniable Authentication Research Articles

VoteGrid: A mobile ballot system for decision making in grid environment

Abstract One of the frustrations of the INDIAN government is the nation’s lack of voter participation. Many voters claim issues are “not relevant” to them. Taken within the context of mobile grid voting, when an individual is within a time and location that is highly related to the ballot’s issue, we predict that they will be more likely to participate in the voting process. In this work, we proposed a deniable authentication mobile voting scheme that not only meets the general requirements of a secure voting system but also is suitable for application over mobile ad-hoc networks. VoteGrid is an online system for public debate and expression of opinions through voting facilities based on Digital Signature. It functions as a national “debate and voting portal” allowing citizens, businesses, politicians and journalists to participate in debates and votes organised by levels of government, subject, etc. It can handle debates and votes at the local, regional and national levels and it is possible to authentify user identity through login with the Digital Signature.

Full and partial deniability for authentication schemes

Deniable authentication is a type of authentication protocol with the special property of deniability. However, there have been several different definitions of deniability in authentication protocols. In this paper, we clarify this issue by defining two types of deniable authentication: In the first type of deniable authentication, the receiver of the authenticated message cannot prove to a third party that the sender has authenticated any message to him. We call this type of deniability full deniability. In the second type of deniable authentication, whilst the receiver can prove to a third party that the sender has authenticated some message to him, but he cannot prove to a third party that the sender has authenticated any particular message to the receiver. We call this type of deniability partial deniability. Note that partial deniability is not implied by full deniability, and that it has applications different from those of full deniability. Consequently, we present two identity-based authentication schemes and prove that one is fully deniable while the other is partially deniable. These two schemes can be useful in different scenarios.

An efficient non-interactive deniable authentication protocol with anonymous sender protection

Deniable authentication protocols satisfy two basic properties: Deniability and the specifiable receiver properties. However, the deniability also damages the sender right. To protect senders, Hwang and Ma first proposed deniable authentication with anonymous sender protection. The sender’s anonymity is also used to protect the sender’s privacy. To reduce the computation cost, an efficient deniable authentication protocol is proposed. Our new protocol not only achieves the two properties but also provides the protection of sender and receiver to keep the privacy of the sender and receiver. Though the sent message is forgeable by receivers, but the sender can provide evidence to prove the message was really sent by him/her. Due to the efficient performance, our protocol is more practical than the other protocols in the real world.

An efficient non-interactive deniable authentication scheme based on trapdoor commitment schemes

Deniable authentication scheme is one of useful tools for secure communications. The scheme allows a sender to prove the authenticity of a message to a specified receiver without permitting the receiver to prove that the message was authenticated by the sender. Non-interactive schemes are more attractive than interactive schemes in terms of communication overhead, and thus several non-interactive deniable authentication scheme have been proposed. In this paper, we propose an efficient non-interactive deniable authentication scheme based on trapdoor commitment scheme. We construct an efficient trapdoor commitment scheme which provides very efficient commitment evaluation operation. Then we design an efficient non-interactive deniable authentication scheme by using the trapdoor commitment scheme. We also prove the security of our scheme under firmly formalized security model.

Coercion-resistant electronic voting scheme

Based on some security techniques of secret sharing,mix-net,deniable authentication etc,a coercion-resistant electronic voting scheme was proposed,in which the problem on forcing voter to vote and buying vote could be solved due to meeting the essential requirements of e-voting scheme.It was infeasible for the coercer to determine if a coerced voter complied with the demands in the scheme,so it improved coercion-resistance of electronic voting.

Robust Deniable Authentication Protocol

Deniable authentication protocol is a new technique of modern cryptography. The protocol not only enables an intended receiver to identify the source of a received message, but also prevents a third party from identifying the source of the message. Recently, Shao et al. pointed out that Wang et al.'s deniable authentication protocol based on ElGamal cryptosystem is insecure to a person-in-the-middle attack; that is, in the whole process, the receiver cannot be aware of the existence of this adversary as well as the modification of the messages. Furthermore, they also presented a modification of Wang et al.'s protocol to overcome the security flaw. However, this paper demonstrates that Shao et al.'s improved protocol is still susceptible to a malicious receiver's impersonation attack. To mitigate this security breach, we propose a robust deniable authentication protocol based on ElGamal cryptography.

A Secure Internet Voting Protocol Based on Non-interactive Deniable Authentication Protocol and Proof Protocol that Two Ciphertexts are Encryption of the Same Plaintext

Internet voting protocol is the base of the Internet voting systems. Firstly, an improved proof protocol that two ciphertexts are encryption of the same plaintext is introduced. Secondly, a receipt-free and coercion-resistant Internet voting protocol based on the non-interactive deniable authentication protocol and an improved proof protocol that two ciphertexts are encryption of the same plaintext is developed. Thirdly, we analyze the proposed Internet voting protocol. The proposed Internet voting protocol has the properties of universal verifiability, receiptfreeness and coercion-resistance. At the same time the proposed protocol is with the weak physical assumption. Lastly, we compare security properties of the several typical Internet voting protocols with our present protocol.

New Approaches for Deniable Authentication

Deniable Authentication protocols allow a Sender to authenticate a message for a Receiver, in a way that the Receiver cannot convince a third party that such authentication (or any authentication) ever took place. We present two new approaches to the problem of deniable authentication. The novelty of our schemes is that they do not require the use of CCA-secure encryption (all previous known solutions did), thus showing a different generic approach to the problem of deniable authentication. These new approaches are practically relevant as they lead to more efficient protocols. In the process we point out a subtle definitional issue for deniability. In particular, we propose the notion of forward deniability, which requires that the authentications remain deniable even if the Sender wants to later prove that she authenticated a message. We show that a simulation-based definition of deniability, where the simulation can be computationally indistinguishable from the real protocol does not imply forward deniability. Thus, for deniability one needs to restrict the simulation to be perfect (or statistically close). Our new protocols satisfy this stricter requirement.

Fingerprint Biometric-based Self-Authentication and Deniable Authentication Schemes for the Electronic World

This paper presents fingerprint biometric-based self-authentication and deniable authentication schemes, which enable a receiver to identify source of the message but not to prove the identity of the sender to a third party. At first, we identify the security flaws of some recently proposed deniable authentication schemes by three application scenarios, and prove that those schemes are vulnerable to impersonation and eavesdropping attacks. For remedy, we propose two-factor-based self-authentication and deniable authentication schemes in which, firstly, each user has to perform self-authentication by something he knows (password) and something he is (biometrics), and then he can accomplish the transaction, e.g., e-commerce. Security analysis shows that the proposed schemes can overcome the security pitfalls of the previous schemes and are secure, reliable and practicable with high potential to be used in the electronic world.

A Secure Non-Interactive Deniable Authentication Protocol with Strong Deniability Based on Discrete Logarithm Problem and its Application on Internet Voting Protocol

A Secure Non-Interactive Deniable Authentication Protocol with Strong Deniability Based on Discrete Logarithm Problem and its Application on Internet Voting Protocol

A non-interactive deniable authentication scheme based on designated verifier proofs

A deniable authentication protocol enables a receiver to identify the source of the given messages but unable to prove to a third party the identity of the sender. In recent years, several non-interactive deniable authentication schemes have been proposed in order to enhance efficiency. In this paper, we propose a security model for non-interactive deniable authentication schemes. Then a non-interactive deniable authentication scheme is presented based on designated verifier proofs. Furthermore, we prove the security of our scheme under the DDH assumption.

A simple deniable authentication protocol based on the Diffie–Hellman algorithm

Deniable authentication protocol is a new authentication mechanism in secure computer communication, that not only enables an intended receiver to identify the source of a received message but also prevents a third party from identifying the source of the message. In this paper, based on the Diffie–Hellman algorithm, we propose a new simple deniable authentication protocol from a provably secure simple user authentication scheme. Compared with other deniable authentication protocols, our proposed protocol not only achieves the property of deniable authenticity, but also provides the mutual authentication between the sender and the intended receiver and the confidentiality.

An electronic voting protocol with deniable authentication for mobile ad hoc networks

In this article, we propose a deniable electronic voting authentication protocol for mobile ad hoc networks, which meets the essential requirements of a secure e-voting system. Due to the characteristics, constraints, and security requirements of mobile ad hoc networks, our protocol does not require the aid of any centralized administration and mobile nodes could cooperate with each other to securely facilitate e-voting. Finally, the proposed protocol provides the ability to deniable authentication. When a legal voter casts a vote with this voting system, he/she can deny that he/she has voted for a third party and the third party cannot judge who votes.

A new approach for UC security concurrent deniable authentication

Deniable authentication protocols allow a sender to authenticate a message for a receiver, in a way which the receiver cannot convince a third party that such authentication ever took place. When we consider an asynchronous multi-party network with open communications and an adversary that can adaptively corrupt as many parties as it wishes, we present a new approach to solve the problem of concurrent deniable authentication within the framework of universally composable (UC) security. We formulate a definition of an ideal functionality for deniable authentication. Our constructions rely on a modification of the verifiably smooth projective hashing (VSPH) with projection key function by trapdoor commitment. Our protocols are forward deniable and UC security against adaptive adversaries in the common reference string model. A new approach implies that security is preserved under concurrent composition of an unbounded number of protocol executions; it implies non-malleability with respect to arbitrary protocols and more. The novelty of our schemes is the use of witness indistinguishable protocols and the security is based on the decisional composite residuosity (DCR) assumption. This new approach is practically relevant as it leads to more efficient protocols and security reductions.

Design of Fully Deniable Authentication Service for E-mail Applications

Secure electronic mail (e-mail), such as PGP and S/MIME, uses digital signature to provide message authentication, which also provides the undesired non-repudiation evidence of the message sender. In this paper, we introduce a fully deniable e-mail authentication service. Our design can be easily integrated into the current PGP and S/MIME to provide message authentication without non-repudiation evidence. This feature can protect personal privacy of the message sender in most personal communication.

Deniable Authentication Protocol Resisting Man-in-the-Middle Attack

Deniable Authentication Protocol Resisting Man-in-the-Middle Attack

Erratum to “Non-interactive deniable authentication protocol based on factoring”[Computer Standards & Interfaces 27 (2005) 401–405

Erratum to “Non-interactive deniable authentication protocol based on factoring”[Computer Standards & Interfaces 27 (2005) 401–405

Universally Composable Security Concurrent Deniable Authentication Based on Witness Indistinguishable

A new approach and an idea for exploration are presented to the concurrent deniable authentication based on witness-indistinguishable (WI) within the framework of universally composable (UC) security. A definition of an ideal functionality for deniable authentication is formulated. A new deniable authentication protocol is proposed based on two primitives of the verifiably smooth projective Hashing (VSPH) and non-committing encryptions (NCE). This new approach is practically relevant to VSPH based on the Decisional Diffie-Hellman (DDH) assumption and NCE based on the decisional composite residuosity (DCR) assumption. Compared with a timing constraint and public directory model, simulation of the concurrent protocols is not needed to restrict an adversary capability in a common reference string (CRS) model. The protocols are forward deniable and UC security against adaptive adversaries. Unlike previous proposals with the CCA2 public-key cryptosystem or multi-trapdoor commitments paradigm, the new paradigm leads to more efficient protocols.

A New ID-Based Deniable Authentication Protocol

Deniable authenticated protocol is a new cryptographic authentication protocol that enables a designated receiver to identify the source of a given message without being able to prove the identity of the sender to a third party. Therefore, it can be applied to some particular situations in electronic commerce. In this paper, we formally define the security model for the non-interactive ID-based deniable authentication protocol and present a new efficient ID-based deniable authentication protocol based on RSA assumption. What's more, we also use the techniques from provable security to analyze the security of our proposed protocol.

Zaps and Their Applications

A zap is a 2‐round, public coin witness‐indistinguishable protocol in which the first round, consisting of a message from the verifier to the prover, can be fixed “once and for all” and applied to any instance. We present a zap for every language in NP, based on the existence of noninteractive zero‐knowledge proofs in the shared random string model. The zap is in the standard model and hence requires no common guaranteed random string. We present several applications for zaps, including 3‐round concurrent zero‐knowledge and 2‐round concurrent deniable authentication, in the timing model of Dwork, Naor, and Sahai [J. ACM, 51 (2004), pp. 851–898], using moderately hard functions. We also characterize the existence of zaps in terms of a primitive called verifiable pseudorandom bit generators.