Masquerade: Verifiable Multi-Party Aggregation with Secure Multiplicative Commitments

The article presents a comprehensive overview of zero-knowledge proof (ZKP) protocols as a fundamental concept of modern cryptography. The historical background of their emergence and the main properties ensuring reliability and confidentiality, i.e., completeness, soundness, and zero-knowledge — are considered. A classification of protocols into interactive and non-interactive ones is provided, with a special focus on modern solutions such as the zk-SNARK and the zk-STARK. The mathematical foundations of ZKPs are described in detail, including discrete logarithm proofs, the use of homomorphic encryption, polynomial commitments, hashing, and elliptic curves. Practical application areas are analyzed, including cryptocurrencies (Zcash, Ethereum), authentication systems, digital identity, and electronic voting. The advantages of using ZKPs are shown, such as enhanced privacy, reduced need for trusted intermediaries, and strengthened security. At the same time, key challenges are outlined, including scalability, implementation complexity, the problem of trusted setup, and potential vulnerability to quantum computing. It is concluded that zero-knowledge proof protocols are a powerful tool for ensuring confidentiality and reliability of digital systems, while further research is aimed at creating more efficient and quantum-resistant solutions.

Suguru is a paper and pencil puzzle invented by Naoki Inaba. The goal of the game is to fulfil a grid with numbers between 1 and 5 and to respect three simple constraints. In this paper we design a physical Zero-Knowledge Proof (ZKP) protocol for Suguru. A ZKP protocol allows a prover (P) to prove that he knows a solution of a Suguru grid to a verifier (V) without leaking any information on the solution. For constructing such a physical ZKP protocol, we only rely on a small number of physical cards and an adapted encoding. For a grid of Suguru with n cells, we only use \(5n+5\) cards. Moreover, we prove the three classical security properties of a ZKP: completeness, extractability, and zero-knowledge.

Often clients (e.g., sensors, organizations) need to outsource joint computations that are based on some joint inputs to external untrusted servers. These computations often rely on the aggregation of data collected from multiple clients, while the clients want to guarantee that the results are correct and, thus, an output that can be publicly verified is required. However, important security and privacy challenges are raised, since clients may hold sensitive information. In this paper, we propose an approach, called verifiable additive homomorphic secret sharing (VAHSS), to achieve practical and provably secure aggregation of data, while allowing for the clients to protect their secret data and providing public verifiability i.e., everyone should be able to verify the correctness of the computed result. We propose three VAHSS constructions by combining an additive homomorphic secret sharing (HSS) scheme, for computing the sum of the clients’ secret inputs, and three different methods for achieving public verifiability, namely: (i) homomorphic collision-resistant hash functions; (ii) linear homomorphic signatures; as well as (iii) a threshold RSA signature scheme. In all three constructions, we provide a detailed correctness, security, and verifiability analysis and detailed experimental evaluations. Our results demonstrate the efficiency of our proposed constructions, especially from the client side.

Public auditing for cloud storage is of critical importance as the users relies on semi-trusted cloud storage service for data sharing which does not guarantee/assure the integrity of the data being stored. With public auditing of clouds, users resort to a third party auditor (TPA) who verify and assure the internal consistency/lack of corruption of their data in cloud storage services. Despite the good work previously done by researchers in auditing while preserving privacy, still available mechanisms do not efficiently conceal users' privacy from TPA during sharing of data and yet supporting data and group dynamics. In this paper, we propose privacypreserving auditing scheme that exploits the ring signature to calculate verifications needed to audit data integrity.In this proposed approach, the identities of the user are kept private from public verifier and dynamic groups are supported -that is a new user can be added into the group and an existing group member can be revoked during data sharing.

Aggregator oblivious encryption was proposed by Shi et al. (NDSS 2011), where an aggregator can compute an aggregated sum of data and is unable to learn anything else (aggregator obliviousness). Since the aggregator does not learn individual data that may reveal users’ habits and behaviors, several applications, such as privacy-preserving smart metering, have been considered. In this paper, we propose aggregator oblivious encryption schemes with public verifiability where the aggregator is required to generate a proof of an aggregated sum and anyone can verify whether the aggregated sum has been correctly computed by the aggregator. Though Leontiadis et al. (CANS 2015) considered the verifiability, their scheme requires an interactive complexity assumption to provide the unforgeability of the proof. Our schemes are proven to be unforgeable under a static and simple assumption (a variant of the Computational Diffie-Hellman assumption). Moreover, our schemes inherit the tightness of the reduction of the Benhamouda et al. scheme (ACM TISSEC 2016) for proving aggregator obliviousness. This tight reduction allows us to employ elliptic curves of a smaller order and leads to efficient implementation.

The idea of Zero Knowledge Proof (ZKP) was first proposed by Goldwasser, Micali and Racko [S. Goldwasser, et al. 1989.] in 1989. It is a mutual protocol to solve the problem: the prover demonstrates to the verifier that he has some secret information, but after that the verifier doesn’t know what the secret information is. In the verification process, the prover lets out zero information about the secret to the verifier. ZKP can be divided into two basic kinds: interactive and non-interactive zero knowledge proof . Zero knowledge proof protocols are used extensively in the field of information security, such as identity authentication, fair exchange, key agreement, electronic voting and electronic payment system, etc.

Systems for generating and managing digital identities are in the process of being transformed to improve data sharing security and increase decentralization. Addressing both issues, a theoretical solution to create and manage Self-Sovereign Identities (SSI) is proposed using two Zero-Knowledge Proof (ZKP) protocols based on the discrete logarithm difficulty. Automorphism group properties are introduced to link several identities, their identifiers and attributes to produce a proof. The proposed SSI protocol does not encounter the problem of reusing the same secret key as in the case of the initial ZKP Schnorr protocol. The designed protocol ensures minimal disclosure of information to a single trusted third party. In addition, it allows zero disclosure of information to service providers requiring proof of authentication or identification. Such a SSI protocol is compliant with Electronic IDentification And Trust Services (eIDAS) as well as General Data Protection Regulation (GDPR) regulations.

: Authentication is deemed to be a critical function in the operation of tactical wireless ad hoc networks. The dynamic nature and unpredictability of these self - organizing networks requires that new security protocols be deployed that allow users to efficiently gain access to network resources without the burden of a centralized security infrastructure. Authentication protocols based on Zero - Knowledge Proof (ZKP) of identity schemes provide a means for establishing mutual trust between network entities. While many papers have looked at the virtues of ZKP - based authentication protocols from an academic perspective, little work has been carried out to actually deploy and test the protocols in fielded wireless networks. In this paper we present lessons - learned regarding the installation of ZKP - based authentication protocol on processing hardware designed for deployment on AFRL's small unmanned aerial vehicle (UAV) test bed.

Public auditing schemes for cloud storage systems have been extensively explored with the increasing importance of data integrity. A third-party auditor (TPA) is introduced in public auditing schemes to verify the integrity of outsourced data on behalf of users. To resist malicious TPAs, many blockchain-based public verification schemes have been proposed. However, existing auditing schemes rely on a centralized TPA, and they are vulnerable to tempting auditors who may collude with malicious blockchain miners to produce biased auditing results. In this article, we propose a blockchain-based decentralized public auditing (BDPA) scheme by utilizing a decentralized blockchain network to undertake the responsibility of a centralized TPA, and also mitigate the influence of tempting auditors and malicious blockchain miners by taking the concept of decentralized autonomous organization (DAO). A detailed security analysis shows that BDPA can preserve data integrity against tempting auditors and malicious blockchain miners. A comprehensive performance evaluation demonstrates that BDPA is feasible and scalable.

Public auditing is a topic issue as it makes a third party auditor replace user to verify the data integrity. Hence, it handles users' problems such as cannot be on-line all times and with constrained computing resources. However, this technology may reveal user's information to the verifier. Therefore, privacy-preserving should be considered in public auditing. What's more, the existing public auditing schemes are mainly based on signatures what need to transfer signature and message together. This kind of public verification scheme is not suitable in small bandwidth situation. Especially, due to unstable network, it will be difficult to upload large files and cloud server cannot ensure that the message he gets is correct. Message recovery signature is adaptable in this circumstance as it only transfers signature and the message can be recovered from the corresponding valid signature. Moreover, certificate-based schemes have certificate management problem and ID-based schemes have key escrow problem. To solve above problems, in this paper, we proposed a certificateless privacy-preserving public verification scheme which also supports message recovery and dynamic group. What's more, our scheme eliminates problems of certificates management and key escrow. Furthermore, we show that our scheme is secure and efficient in performance analysis.

This paper proposes a methodology to evaluate the maximum power, which can be drawn out from a PV plant on the basis of its geographic location and local weather conditions. These evaluations are carried out through data analytics, starting from an experimental knowledge base, which is built through aggregation of data coming from electric characterization tests, temperature measurements and weather stations. The first part of this methodology is focused on the characterization of irradiance sensors, highlighting the dependency of its measurements on sun elevation angle. The evaluations are then focused on a real application, which consists in a Hetero Junction Intrinsic Thin Layer (HIT) PV panel equipped with temperature sensors. The estimations are obtained by using weather data coming from measurement stations located near the PV panel. The comparison with experimental results highlights the performance of the proposed power prediction method, especially during summer periods.

In wireless sensor networks, data aggregation is critical to network lifetime. It implies that data will be aggregated while flowing from multiple sources to a specific node named sink. The construction of routing trees aware of the data aggregation has a considerable cost and solutions in the literature are not efficient for scenarios where the events are of short duration. This paper presents the Dynamic Data-Aggregation Aware Routing Protocol (DDAARP) for wireless sensor networks. This novel protocol builds dynamic routes, which improve the cost and quality of final routing tree. It also reduces the number of messages necessary to set up a routing tree, maximize the number of overlapping routes, selects routes with the highest aggregation rate, and performs reliable data aggregation transmission. DDAARP was compared with two existing solutions reported in the literature regarding communication costs, delivery efficiency and tree quality created. routing tree built by DDAARP has the best quality of aggregation compared with other algorithms. Results show that DDAARP outperforms these solutions for different scenarios in all evaluations performed. Furthermore, it also shows that the proposed algorithm is a good solution for scenarios with short-term events and for events of long duration.

Integrity protecting hierarchical concealed data aggregation for wireless sensor networks

Energy Internet is considered as a promising approach to solve the problems of energy crisis and carbon emission. It needs to collect user’s real-time data for optimizing the energy utilization. Edge nodes like GWs (gateway) are used for data aggregation to improve the efficiency of the system. Due to a large number of GWs are widely distributed and difficult to be managed, which brings potential security threats for the Energy Internet. Existing data aggregation schemes fails in preventing the adversary from controlling or destroying GWs. In this paper, we propose an IBE-based Device Traceable Privacy-Preserving Aggregation Scheme, named IBE-DTPPA. Increasing the RA (Residential Area) users’ data aggregation integrity verification by BGN Cryptosystem; using IBE Cryptosystem to encrypt aggregation data, calculating ciphertext based on GW’s dynamic ID, realizing the target GW traceability; choosing CC (Control Center) dynamic identity information as public key to realize CC authentication, preventing adversary from using CC’s identity fraudulently. Through extensive analysis, we demonstrate that IBE-DTPPA resists various security threats, and can trace target GW efficiently.

As the number of active Internet of Things (IoT) devices increases, managing and securing the enormous amount of data generated by these devices become harder. With their always‐connected smart meters and internet‐enabled electrical appliances, smart grids (SGs) are major data generation sources in IoT. Traditional SGs store and process their collected data in centralized cloud servers. Secure data aggregation (SDA) protocols play an essential role in efficient and private data collection and storage in cloud‐based SGs. Due to a high number of connected devices, centralized cloud‐based SGs may become inadequate to satisfy the processing and storage needs of the collected data. This article introduces two efficient and lightweight SDA protocols for fog computing‐based SGs (FCSG), namely, FCSG‐DF and FCSG‐P, as a complementary solution for processing and storage needs of cloud‐based SGs. By leveraging the distributed nature and other extended capabilities of fog computing, the proposed SDA protocols have a better response time with less computational overhead. Moreover, the privacy of fine‐grained energy consumption data is preserved with the help of the privacy‐preserving data aggregation processes in the hierarchical fog computing structure of FCSG. Extensive performance evaluation results demonstrate that the proposed protocols have superiority in terms of data transmission and storage efficiency compared to cloud‐assisted schemes without data aggregation. Both protocols are analyzed by comparing their success in transmission and storage efficiencies. Moreover, privacy analysis verifies that both protocols effectively ensure the privacy of the data in each layer.