With the development of location-based services based on smart terminals and positioning technologies, location forgery and privacy leakage become an important issue, making it difficult for the existing methods of proof of location to guarantee the accuracy, authenticity and privacy of user trajectory information. By using the decentralized, non-tamperable and traceable characteristics of blockchain and combining with zero-knowledge proof method, this paper proposes a personal trajectory verification algorithm to provide a solution to solve the limitation of traditional location proof method for trajectory verification problems.
With the proliferation of social networks, user data is increasingly vulnerable to unauthorized access, profiling, and data breaches. Cryptography has emerged as a critical defense mechanism to ensure data confidentiality, integrity, and user privacy. This paper explores the application of modern cryptographic techniques—such as homomorphic encryption, zero-knowledge proofs, and attribute-based encryption—to enhance privacy controls within social networking platforms. It further highlights the challenges of balancing usability with security and presents solutions for deploying cryptographic protocols in dynamic, large-scale environments like Facebook, Twitter, and LinkedIn. The paper concludes with future directions for integrating decentralized privacy models using blockchain-based cryptographic frameworks.
The continuous development of the mobile computing environment has led to the emergence of fintech to enable convenient financial transactions in this environment. Previously proposed financial identity services mostly adopted centralized servers that are prone to single-point-of-failure problems and performance bottlenecks. Blockchain-based self-sovereign identity (SSI), which emerged to address this problem, is a technology that solves centralized problems and allows decentralized identification. However, the verifiable credential (VC), a unit of SSI data transactions, guarantees unlimited right to erasure for self-sovereignty. This does not suit the specificity of the financial transaction network, which requires the restriction of the right to erasure for credit evaluation. This paper proposes a model for VC generation and revocation verification for credit scoring data. The proposed model includes double zero knowledge - succinct non-interactive argument of knowledge (zk-SNARK) proof in the VC generation process between the holder and the issuer. In addition, cross-revocation verification takes place between the holder and the verifier. As a result, the proposed model builds a trust platform among the holder, issuer, and verifier while maintaining the decentralized SSI attributes and focusing on the VC life cycle. The model also improves the way in which credit evaluation data are processed as VCs by granting opt-in and the special right to erasure.
Passwords are currently the king in online authentication. But passwords come with a lot of baggage - how to use them, store them, hide them, and obfuscate them. Every year, there are plenty of cyber-attacks which involves passwords being stolen. These passwords are stored and transmitted over networks and hence, many mistakes can be made while doing so. In this paper, a relatively new form of authentication is explored - one based on the concept of Zero-Knowledge Proof (ZKP). It further explores how ZKP can provide additional security to the authentication mechanism by taking the transmission of passwords out of the picture. This paper also discusses the Replay attack vulnerability present in the non-interactive implementation of ZKP and proposes a two-fold mitigation strategy against the vulnerability.
Distributed Ledger Technology (DLT) and Blockchain Technology (BCT) are options for introducing smart and transitive energy trading via a Know Your Customer or Know Your Client (KYC) system using an Ethereum Blockchain. The most significant context in which BCT can create transformative change is in the verification of other parties in an energy trading system. Currently the KYC trade mostly relies on internal controls to send and receive KYC information across the globe, resulting in slower and error prone data management and governance. BCT can solve this by providing immutable and verifiable data sources. Implementing smart contract addressing, the issue of storing critical data necessary at different stages of KYC and making it verifiable by all stakeholders is of critical importance. The literature review looks at the current research in BCT, programming languages used in BCT, Game Theory, Zero-Knowledge Proofs and energy trading in context to KYC. Having a foundational concept mathematically by creating game theoretic models and a simple computer programming simulation is the first step in the task of creating a true BCT platform that can be used in energy trading for KYC. Simulating the scenarios of n-player games is important to the advancement of this platform. The key result of these games and interaction between traders will help change the trading systems regionally and internationally. This can deliver new ways of working and brings visibility and control to each energy trade. The researcher analyses the strength of the system through the decisions of the traders using infinite games. New trading strategies and BCT resources with different parameters gain a larger market presence in international trade with these proofs, codifications and simulations. A gap exists in the literature in BCT in the creation of game theory algorithms as well as using simulation tools and software and using these methods to create forecasted energy trading scenarios with the implementation of KYC. Looking at an infinite game mathematically and presenting a simple codified computer simulation using Ethereum via Solidity involving a supplier, operator and regulator will give new implications in game theory and conflict-resolution scenarios within context to energy trading and KYC via BCT.
Igor Mazurok, Yevhen Leonchyk, Oleksandr S. Antonenko, Kyrylo S. Volkov
Nowadays, Decentralized Networks based on Blockchain technology are actively researched. A special place in these researches is occupied by Smart Contracts that are widely used in many areas, such as Decentralized Finance (DeFi), real estate, gambling, electoral process, etc. Nevertheless, the possibility of their widespread adoption is still not a solved problem. This is caused by the fact of their limited flexibility and scalability. In other words, Smart Contracts cannot process a large number of contract calls per second, lack of direct Internet access, inability to operate with a large amount of data, etc. This article is devoted to the development of the Sharding Concept for Decentralized Applications (DApps) that are expressed in form of Smart Contracts written in WebAssembly. The aim of the research is to offer a new Concept of Smart Contract that will increase the scaling due to applying the idea of Sharding that allows avoiding doing the same work by all nodes on the Network and flexibility due to the possibility of interaction with the Internet without special Oracles. During the research, decentralized 0ata storages with the possibility of collective decision-making were developed. The scheme of forming Drives that assumes that each Contract is executed by a set of randomly selected nodes that allows avoiding cahoots and prevents Sybil Attack is offered. Such an approach allowed using Drives as a base layer for Smart Contracts. Moreover, Drives can be used as a standalone solution for decentralized data storing. The features of coordination of results of Contracts execution that greatly expands the possibilities of the Contracts compared to Ethereum Smart Contracts, and, in particular, allow the Contracts to interact with the Internet are described. The Rewards Concept that incentivizes all nodes that honestly execute the Contracts, unlike other systems where only the block producer is rewarded, is developed. It is based on the specially developed Proof of Executiona special algorithm that allows detecting all the nodes that honestly execute the Contracts. In order to make the Proof of Execution more compact, an extension for the existing discrete logarithm zero-knowledge proofs that makes it possible to consistently prove knowledge of dynamically expanding set of values with minimal computational and memory complexity so-called Cumulative Discrete Logarithm Zero-Knowledge Proof is developed. Thus, in this article, the new concept of Smart Contracts Sharding empowered by economic leverages is researched. The main advantages of the proposed approach are the possibility of interaction with the Internet and big data processing. Moreover, the mechanism of incentivizing nodes to honestly execute the Smart Contracts is developed. In addition, the Cumulative Proof that is necessary for the cryptographic strength of the specified mechanism is offered and its correctness is proven. The obtained results can be used to implement Smart Contracts in decentralized systems, in particular, working on the basis of Blockchain technology, especially in the case of demanding high bandwidth and performance.
In this paper, we create a single-use and full syntax zero-knowledge proof system, a.k.a zk-Fabric. Comparing with zk-SNARKS and another variant zero-knowledge proofing system, zkBOO and it's variant zkBOO++. We present multiple new approaches on how to use partitioned garbled circuits to achieve a joint zero-knowledge proof system, with the benefits of less overhead and full syntax verification. zk-Fabric based on partitioned garbled circuits has the advantage of being versatile and single-use, meaning it can be applied to arbitrary circuits with more comprehensive statements, and it can achieve the non-interactivity among all participants. One of the protocols proposed within is used for creating a new kind of partitioned garbled circuits to match the comprehensive Boolean logical expression with multiple variables, we use the term "polythitic syntax" to refer to the context-based multiple variables in a comprehensive statement. We also designed a joint zero knowledge proof protocol that uses partitioned garbled circuits
Quiz sites are typically made up of a front end, a back end, and a database of questions. Our objective is to further commonize this structure. Problem verification and solution keeping are aspects that have already been thoroughly studied and modified. However, the fairness of answer validation is often unclear to the end user. We propose a system that reduces the cost of creating a quiz site and a quiz scoring system for e-learning by putting part of the structure on a blockchain. Our system verifies answers using zero-knowledge proofs, stores the answers with Ethereum, an open-source platform for decentralized applications, and tracks them. Blockchain can be used to prevent the falsification of answer records. Ethereum is a new technique that has attracted considerable attention in recent years, and we use its program executions, i.e., smart contracts, to validate answers. After receiving an answer, the system stores it as an Ethereum transaction event.
Jesús García-Rodríguez, Rafael Torres Moreno, Jorge Bernal Bernabé, Antonio Skármeta
Despite the latest efforts to foster the adoption of privacy-enhancing Attribute-Based Credential (p-ABC) systems in electronic services, those systems are not yet broadly adopted. The main reasons behind this are performance efficiency issues, lack of interoperability with standards, and the centralized architectural scheme that relies on a unique Identity Provider (IdP) for credential issuance. To cope with these limitations, this paper describes the first implementation of the Pointcheval–Sanders Multi-Signatures (PS-MS) crypto scheme proposed by Camenisch et al. and its integration in a distributed and privacy-preserving identity management system proposed in OLYMPUS H2020 European research project. Our efficient implementation provides remarkable privacy-preservation features for identity management in online transactions leveraging p-ABC systems, including unforgeability, minimal disclosure of personal data through zero-knowledge proofs, unlinkability in online transactions and fully distributed credential issuance across different IdPs, thereby removing the IdP as a unique point of failure. The performance of the implementation has been exhaustively analyzed and evaluated with different curves, signers and number of attributes, and compared against Identity Mixer, the best known p-ABC system, outperforming significantly the credential issuance and zero-knowledge proving and verification processes (2–4 times less execution time).
Binary Attestation (BA) ist ein Sicherheitsmechanismus, der schon lange zur Sicherstellung der Integrität der auszuführenden Software auf einem Computerssystem verwendet wird. Dies wird durch die Anwendung der Konzepte von Trusted Computing Technologie erreicht. Die Konzepte der Trusted Computing Technologie sind: Trusted Platform Module (TPM), measured/trusted boot und Linux Integrity Measurement Architecture (IMA). Damit die Vertrauenswürdigkeit des Betriebszustandes des Systems überprüft werden kann, wird eine Logdatei erstellt. Diese enthält den Dateinamen und die Hash-Summe der Softwarekomponenten, welche an das TPM gebunden wird. Zu einem späteren Zeitpunkt kann eine entfernte Partei (Verifier) die Evidenz verifizieren, um zu sehen, ob der Betriebszustand des Systems vertrauenswürdig ist. Dies wird als Remote Attestation (RA) bezeichnet.Auf den Systemen im Bereich der Cyber-physische Systeme (z. B.: Energie Netze und Kernkraftwerke) und im Bereich der Verkehrsmittel (z. B.: Züge und Automobil Fahrzeuge) laufen mehrere Anwendungen von verschiedenen Herstellern. Bei bisherigen Ansätzen der BA, werden alle Einträge der Logdatei von allen laufenden Anwendungen aller Hersteller während der RA an die entfernte Partei preisgegeben. Daher gewährleistet die Binary Remote Attestation keine Privatheit. Diese Masterarbeit adressiert die genannte Schwäche von der Binary Remote Attestation indem es eine Privacy-Preserving Remote Attestation Ansatz erstellt. Im Kern der Arbeitsteht die Konzeptionierung eines Ansatzes, welches den Trusted Computing Sektor mit Privacy-Enhancing Technologie verknüpft. Der Ansatz bewahrt die Privatheit, indem alle Logeinträge verschleiert werden. Dabei werden dem Verifier nur die jeweilig zugehörigen Einträge offengelegt. Dadurch kann der Attester dem Verifier durch die Anwendung des Schnorr Non-Interactive Zero-Knowledge Proofs über eine elliptische Kurve (Schnorr-Signatur) beweisen, dass es sich bei den ausgeblendeten Einträgen um die tatsächlich laufende Anwendung auf dem System des Attesters handelt, ohne die anderen Einträge preiszugeben. Dieser Ansatz wird in dieser Arbeit als Proof-of-Concept umgesetzt. Die Leistung und die Privatheit des Proof-of-Concepts wurden in dieser Arbeit analysiert. Hierdruch wird gezeigt, dass die Privatheit gegenüber der entfernten Partei gewährleistet wird, während die Integrität und Authentizität des Betriebszustands des Systems vom Attester sichergestellt wird. Die Gewährleistung der Privatheit geht allerdings mit einem Anstieg der benötigten Ressourcen einher.
Abstract Introduction/Objective My role model when I was a medical technologist intern was a chief pathologist who taught me to speak up when something is unsafe and to serve willingly, do what is right, be fair and excellent in work. His character impacted my whole life and career. Every moment matters; life is precious and something to protect. The patient and their care teams depend upon accurate, safe and high-quality clinical laboratory tests result to achieve positive patient outcomes. Methods/Case Report Clinical Practice Results (if a Case Study enter NA) We can do better. Everybody can be surveyors with greater understanding of pathophysiologic processes in disease, extensive experience working in laboratories and in-depth knowledge about complaince, quality, mistake-proofing care, patient-focused and laboratory management. Diagnostic testing would be the method to screen for disease, confirm disease, and monitor disease in hopes of secondary prevention - to identify latent disease to “catch it early.” The screening tests could be anything from newborn screening for inborn metabolism errors, adult screening tests (like mammograms, pap smears, and colonoscopies), to high-risk population screenings to detect HIV, RPR, and gonorrhea. The disease must have a high prevalence to justify the expense of therapy and should be detectable before symptoms arise. The test must not have many false positives but extremely high sensitivity. The results of these tests could lead to the three different methods of prevention. Primary prevention would reduce the risk of developing cardiovascular disease or stroke. Secondary prevention would detect the disease early to prevent progression of the disease. Tertiary prevention would reduce disabilty and promotion of rehabilitation from the disease like strokes or rehab programs. Conclusion In conclusion, this information provides clinicians with a laboratory test menu guidelines to improve clinical practice. We can all learn well to focus on what really matters. Together, we can make healthcare better, more patient-centered, less costly, and safer.
Songqi Wu, Jin Li, Fenghui Duan, Yueming Lu · 6 authors
This paper introduces the mainstream secure multi-party computing technology in the blockchain, which provides a reference for further research in the blockchain field. First, we analyze the privacy protection issues in the blockchain and conclude that secure multi-party computing can make up for the security flaws in the blockchain. Secondly, we summarize the developing secure multi-party computing technology based on blockchain, which are the Zero-knowledge proof scheme, the secret sharing scheme, and the homomorphic encryption scheme. At the same time, we have conducted a security analysis of the multi-party computing technology in the blockchain, and believe that these three technologies can well solve the privacy protection problem in the blockchain. Finally, we look forward to the development trend of the secure multi-party computing in the blockchain, which is expected to solve the problems of poor scalability, key distribution, and non-resistance to quantum attacks. Although the secure multi-party computing technology in the blockchain is still in the development stage, the combination of cryptography and blockchain will become the mainstream development trend in the future.
5G has Introduced the primary and secondary authentication procedures to authenticate the user equipment requesting access to mobile network operators (MNOs) and service providers (SPs) data networks, respectively. However, the possibility of running distributed denial of service (DDoS) attacks on the MNO 5G core network (CN) and the SPs data networks still remains. In this paper, we introduce a zero- knowledge proof (ZKP) authentication algorithm called Partial- ID ZKP that authenticates users without revealing their service credentials. We show that Partial-ID ZKP has completeness and soundness properties. Based on Partial-ID ZKP, we then propose an extensible authentication protocol called EAP-ZKP that can be used in primary and secondary authentications to mitigate DDoS attacks at the CN edge. Finally, as a proof of concept, we implement EAP-ZKP in the 5G authentication procedure. Using the 5G simulators free5GC and gnbsim, we show that EAP-ZKP significantly reduces the authentication time for fake authentication attempts during DDoS attacks. Results also demonstrate that EAP-ZKP is able to recognize DDoS attack authentication attempts in about 10 msec. Interestingly, for the legitimate authentication attempts, the average authentication time slightly increases from 3.05 sec in current 5G authentication protocols to 3.06 sec in EAP-ZKP. This indicates that EAP-ZKP is promising for Beyond 5G.
인증 프로세스는 사용자가 합법적인지 확인하는 데 사용되어야 하는 주요 단계이며, 사용자가 합법적인 사용자인지 확인하고 해당 사용자에게만 액세스 권한을 부여하는 데 사용되어야 한다. 최근에는 로그인 프로세스에 보안 계층을 추가하여 인증에 하나의 요소만 사용하는 취약점을 해결하기 위해 대부분의 애플리케이션에서는 이중인증과 OTP체계를 사용하고 있지만, 이 방법도 허가 없이 사용자 계정에 액세스할 수 있는 방법이 알려져 보안에 취약하다. 본 논문에서는 최소한의 개인정보만을 노출 조건으로 사용자를 인증하는 블록체인의 Smart Contract 기반으로 영지식(ZKP:Zero Knowledge Proofs)개인정보 인증 기법을 제안한다. 이는 블록체인 기술을 기반으로 인증 프로세스에 많은 보안 기술을 제공하고, 개인정보 인증을 기존의 인증방식보다 안전하게 수행할 수 있다는 장점이 있다.
In known constructions of classical zero-knowledge protocols for NP, either of zero-knowledge or soundness holds only against computationally bounded adversaries. Indeed, achieving both statistical zero-knowledge and statistical soundness at the same time with classical verifier is impossible for NP unless the polynomial-time hierarchy collapses, and it is also believed to be impossible even with a quantum verifier. In this work, we introduce a novel compromise, which we call the certified everlasting zero-knowledge proof for QMA. It is a computational zero-knowledge proof for QMA, but the verifier issues a classical certificate that shows that the verifier has deleted its quantum information. If the certificate is valid, even unbounded malicious verifier can no longer learn anything beyond the validity of the statement. We construct a certified everlasting zero-knowledge proof for QMA. For the construction, we introduce a new quantum cryptographic primitive, which we call commitment with statistical binding and certified everlasting hiding, where the hiding property becomes statistical once the receiver has issued a valid certificate that shows that the receiver has deleted the committed information. We construct commitment with statistical binding and certified everlasting hiding from quantum encryption with certified deletion by Broadbent and Islam [TCC 2020] (in a black box way), and then combine it with the quantum sigma-protocol for QMA by Broadbent and Grilo [FOCS 2020] to construct the certified everlasting zero-knowledge proof for QMA. Our constructions are secure in the quantum random oracle model. Commitment with statistical binding and certified everlasting hiding itself is of independent interest, and there will be many other useful applications beyond zero-knowledge.
Abstract: Evolution and modernization have brought about progress in technology and this has led to the reduction in privacy & internet security due to an increase in cybercrime and threats. As a result of this turn of events, Cryptography is now being used as a means of keeping information of any kind safe from third party individual(s). Research has shown that with the Encryption of information, third party individual(s) have no chance or less chance of getting past this security measure. Hence, Cryptographers keep improving algorithms to make it impossible for a third party to decrypt this information without the key which is where database Privacy and Security come in. The database contains all the information which is a major asset, there are encryptions which can be used at different levels to provide security. Lastly, for encryption algorithms which are breached by unknown third-party individual(s), the zero knowledge of proof helps to figure out the identity of this individual. They are an extremely interesting and useful construct. They are fascinating because of their definition, which is mutually opposed, their applicability is very vast in cryptography; they are used to restrict the malevolent users to work according to the protocol. Zero-knowledge serve as a good medium to understand the problems regarding cryptographic protocols. Keywords: Cipher, Encryption, Decryption, Key, Security, Database, Zero-Knowledge
Ceren Kocaoğullar, Arthur Gervais, Benjamin Livshits
While quantitative automation related to trading crypto-assets such as ERC-20 tokens has become relatively commonplace, with services such as 3Commas and Shrimpy offering user-friendly web-driven services for even the average crypto trader, we have not yet seen the emergence of on-chain trading as a phenomenon. We hypothesize that just like decentralized exchanges (DEXes) that by now are by some measures more popular than traditional exchanges, process in the space of decentralized finance (DeFi) may enable attractive online trading automation options. In this paper we present ChainBot, an approach for creating algorithmic trading bots with the help of blockchain technology. We show how to partition the computation into on- and off-chain components in a way that provides a measure of end-to-end integrity, while preserving the algorithmic "secret sauce". Our system is enabled with a careful use of algorithm partitioning, zero-knowledge proofs and smart contracts. We also show that with layer-2 (L2) technologies, trades can be kept private, which means that algorithmic parameters are difficult to recover by a chain observer. Our approach offers more transparent access to liquidity and better censorship-resistance compared to traditional off-chain trading approaches. We develop a sample ChainBot and train it on historical data, resulting in returns that are up to 2.4x the buy-and-hold strategy, which we use as our baseline. Our measurements show that across 1000 runs, the end-to-end average execution time for our system is 48.4 seconds. We demonstrate that the frequency of trading does not significantly affect the rate of return and Sharpe ratio, which indicates that we do not have to trade at every block, thereby significantly saving in terms of gas fees. In our implementation, a user who invests \$1,000 would earn \$105, and spend \$3 on gas; assuming a user pool of 1,000 subscribers.
Jingchi Li, Shaohua An, Honglin Ji, Xingfeng Li · 6 authors
For high-capacity and short-reach applications, carrier-assisted differential detection (CADD) has been proposed, in which the optical field of a complex-valued double sideband (DSB) signal is reconstructed without using a sharp-edge optical bandpass filter or local oscillator laser. The CADD receiver features a transfer function with periodical nulls in the frequency domain, while the signal-signal beat interference (SSBI) is severely amplified around the frequency nulls of the transfer function. Since the null magnitude at the zero frequency is inevitable, a guard band is required between the carrier and the signal, leading to a higher receiver bandwidth and implementation cost. To reduce the needed guard band, we propose a parallel dual delay-based CADD (PDD-CADD), in which an additional delay is placed parallel to the original delay in the conventional CADD. By this means, the modified transfer function has a sharper roll-off edge around the zero frequency. Consequently, the requirement on the guard band can be relaxed, which maximizes the bandwidth utilization of the system. The parallel delay is first optimized through numerical simulation. We then perform a proof-of-concept experiment to transmit a 100-Gb/s orthogonal frequency division multiplexing (OFDM) 16-ary quadrature amplitude modulation (16-QAM) signal over an 80-km single-mode fiber (SMF). After the fiber transmission, the proposed PDD-CADD can reduce the required guard band from 3 to about 1.2 GHz compared with the single delay-based conventional CADD. To our best knowledge, for the direct detection of a single polarization complex-valued DSB signal without using a sharp-roll-off optical filter, we achieve a record electrical spectral efficiency of 5.9 b/s/Hz.
The vast majority of communication on the Internet and private networks heavily relies on Public-key infrastructure (PKI). One possible solution, to avoid complexities around PKI, is to use Password Authenticated Key-Exchange (PAKE) protocols. PAKE protocols enable a secure communication link between the two parties who only share a low-entropy secret (password). PAKEs were introduced in the 1990s, and with the introduction of the first security models and security proofs in the early 2000s, it was clear that PAKEs have a potential for wide deployment - filling the gap where PKI falls short. PAKEs’ PKI-free nature, resistance to phishing attacks and forward secrecy are just some of the properties that make them interesting and important to study. This dissertation includes three works on various aspects of PAKEs: an attack on an existing PAKE proposal, an application of PAKEs in login (for password leak detection) and authentication protocols (HoneyPAKEs), and a security analysis of the J-PAKE protocol, that is used in practice, and its variants. In our first work, we provide an empirical analysis of the zkPAKE protocol proposed in 2015. Our findings show that zkPAKE is not safe against offline dictionary attacks, which is one of the basic security requirements of the PAKE protocols. Further, we demonstrate an implementation of an efficient offline dictionary attack, which emphasizes that, it is necessary to provide a rigorous security proof when proposing a new protocol. In our second contribution, we propose a combined security mechanism called HoneyPAKE. The HoneyPAKE construction aims to detect the loss of password files and ensures that PAKE intrinsically protects that password. This makes the PAKE part of the HoneyPAKE more resilient to server-compromise and pre-computation attacks which are a serious security threat in a client-server communication. Our third contribution facilitates the wider adoption of PAKEs. In this work, we revisit J-PAKE and simplify it by removing a non-interactive zero knowledge proof from the last round of the protocol and derive a lighter and more efficient version called sJ-PAKE. Furthermore, we prove sJ-PAKE secure in the indistinguishability game-based model, the so-called Real-or-Random, also satisfying the notion of perfect forward secrecy.