The traditional ways of handling academic credentials are considered inefficient, expensive, and very vulnerable to fraud and data alteration as they rely on single-point databases. To counter these drawbacks, the authors of this paper propose a novel conception relying on blockchain technology with its central traits such as decentralization, immutable state, and cryptographic security. Under such framework, all the academic credentials are stored in a distributed ledger as non-variable and visible entries, where each credential is securely encrypted, stamped with the time of its creation, and linked in an irreversible chain, thus practically eliminating the possibility of their falsification or unauthorized change without the agreement of the entire network. The verification process is decentralized so that employers, educational institutions, and students can instantly and directly authenticate the credentials through the blockchain thereby cutting the intermediaries and considerably shortening the administrative delays and reducing overheads. Moreover, smart contracts contribute to further efficiency by automatically taking care of the issuance, management, and verification of credentials according to the pre-defined rules, thus ensuring consistency and accuracy. However, the system still offers the highest user control and privacy through the provision of tools like digital wallets and decentralized identifiers for the students to own and manage their digital credentials. These tools also give the students power to decide who can access their records and under what conditions. To ensure the integrity and confidentiality of the data, advanced security technologies such as cryptographic hashing and zero-knowledge proofs are deployed while still allowing transparency to the process of verification.
Archy Renaldy Pratama Nugraha, Yandra Arkeman, Irman Hermadi, Yani Nurhadryani
Digital identity verification in e-governance faces a trilemma between security, scalability, and regulatory compliance with Indonesia's Personal Data Protection Law (UU PDP). To resolve this, in this paper, we propose the ZMC-Framework, a blockchain-based hybrid architecture integrating Zero-Knowledge Proofs (ZKPs) for privacy-preserving verification and Merkle Trees for efficient, scalable data integrity on-chain. Its core innovation is a Legal Proof Protocol with 3+1 parameter augmentation, which cryptographically binds static identifiers to a user-controlled secret, ensuring compliance with UU PDP (data minimization) and UU ITE (authentication integrity) while aligning with key controls of the international ISO/IEC 27001:2022 standard. Evaluated on Polygon Mainnet, the framework demonstrates 29.9% lower operational costs for batch verifications and 50% better storage efficiency compared to pure ZKP systems. These results validate a practical solution to the verification trilemma, providing a secure, scalable, and legally sound foundation for public service identity management in Indonesia's digital governance ecosystem.
Donggoo Kim, Rajesh Upadhayaya, Milosz Bator, Tao Le
Proof of Reserves (PoR) enables centralized crypto exchanges to demonstrate that on-chain reserves are sufficient to cover customer liabilities. However, existing approaches, including Merkle-tree-based proofs and zero-knowledge PoR systems, remain difficult for everyday users to verify in practice, resulting in limited participation and weakened transparency. We introduce LPOR, a layered, usability-focused PoR framework that separates lightweight user-side checks from auditor-level cryptographic verification, enabling non-technical users to verify inclusion and publicly recompute total liabilities with minimal friction. By lowering verification barriers, LPOR increases user participation and substantially improves the probability of detecting omitted liabilities. We evaluate its scalability and omission detectability at a multi-million-user scale.
S. Praveena, T. Arasulingam, M. Dineshkumar, P. Puvirajan · 7 authors
The rapid expansion of digital commerce has brought forward new challenges in payment security and transactional trust. Buyers and sellers engaging in online platforms face persistent threats such as payment fraud, unauthorized fund diversions, delayed settlements, and an overreliance on centralized financial intermediaries. Traditional mechanisms, which route payments through banks and payment gateway providers, often introduce additional costs while creating points of vulnerability that undermine consumer confidence. This paper proposes a blockchain-driven decentralized crypto escrow payment framework designed to address these shortcomings in a fundamental way. Rather than routing buyer payments directly to merchant accounts, the system temporarily secures those funds within a smart contract-governed escrow until all agreed-upon transaction conditions have been satisfied — including verified order fulfilment and successful product delivery. In the event of a dispute or transaction failure, the system enforces pre-coded refund protocols without requiring manual intervention. The proposed framework is expected to strengthen the relationship between buyers and sellers, meaningfully raise the bar for payment security, and deliver a transparent, auditable transaction environment through the principles of decentralized finance.
Bitcoin is permissionless and does not rely on any central administrator, which gives it strong censorship resistance. At the same time, it is important to incentivize miners to behave in ways that align with the interests of the system as a whole. This paper asks whether miners are individually incentivized to propagate blocks, one of the most fundamental processes in Bitcoin. Miners collectively maintain the blockchain by generating blocks and disseminating them across the network. If miners have an incentive not to propagate some blocks, this would indicate a fundamental flaw in Bitcoin's incentive design. Although prior work has studied how propagation delays affect forks and mining rewards, it has not fully characterized miners' incentives to improve block propagation under different tie-breaking rules. To address this gap, we derive analytical reward expressions for each tie-breaking rule based on a blockchain network model that captures the effect of forks on mining fairness. These expressions explicitly characterize how block propagation delays, hashrate distribution, and tie-breaking rules jointly determine mining rewards. We then use them to analyze miners' incentives to improve block propagation. Our results show, for example, that miners have no mining-reward incentive to relay blocks generated by other miners. By contrast, under the first-seen rule, every non-majority miner is incentivized to receive other miners' blocks more quickly and to propagate its own blocks more quickly. Finally, we compare tie-breaking rules and identify a trade-off between propagation incentives and mining fairness. In particular, the first-seen rule provides the strongest incentives to reduce propagation delays, but it also worsens mining fairness the most.
(English) The accelerated adoption of digital services has highlighted the need for trust-minimized computation, where parties can verify the correctness of computations without re-executing them or revealing sensitive data. Zero-knowledge proof systems, including SNARKs and STARKs, provide cryptographic guarantees of correctness, privacy, and succinct verifiability, enabling applications in scalable blockchains, privacy-preserving identity systems, and verifiable federated learning. This thesis addresses key inefficiencies in constraint-based zero-knowledge proof systems at the arithmetization layer. The research focuses on two complementary problems: optimizing binary comparisons within Rank-1 Constraint Systems (R1CS), and extending the expressiveness of STARKs through an Extended Algebraic Intermediate Representation (eAIR). The first contribution presents a weighted accumulation method for implementing strict binary comparisons in R1CS. Traditional approaches generate a large number of constraints due to the lack of native comparison and control-flow operations in the R1CS model, forcing costly bit-by-bit decompositions and creating performance bottlenecks. The proposed weighted accumulation method significantly reduces constraint overhead without compromising system security or correctness, achieving substantial efficiency improvements over the lexicographic approach. The second contribution introduces the eSTARK protocol, which extends standard STARKs by enabling the concise handling of complex constraints such as lookups, permutations, and copy constraints. These operations are difficult to encode efficiently in standard AIR. The eSTARK protocol integrates vector commitment arguments and polynomial optimizations, providing a flexible and user-friendly framework for representing a broader class of computations without introducing unnecessary arithmetization overhead. Both contributions address practical limitations of current zero-knowledge proof systems. The first focuses on reducing constraint complexity for common operations, while the second expands the expressiveness of the proof system itself. Together, they demonstrate the importance of arithmetization-level optimizations for improving the efficiency and usability of zero-knowledge proofs. (Català) L’adopció accelerada de serveis digitals ha posat en relleu la necessitat de computació amb confiança mínima, on les parts poden verificar la correcció dels càlculs sense haver de tornar-los a executar ni revelar dades sensibles. Els sistemes de proves de coneixement zero, incloent-hi SNARKs i STARKs, ofereixen garanties criptogràfiques de correcció, privacitat i verificabilitat concisa, permetent aplicacions en blockchains escalables, identitat preservant la privacitat i aprenentatge federat verificable. Aquesta tesi aborda les principals ineficiències en els sistemes de proves ZK basats en restriccions a la capa d’aritmetització. La recerca se centra en dos problemes complementaris: optimitzar les comparacions binàries dins dels Rank-1 Constraint Systems (R1CS) i ampliar l’expressivitat dels STARKs mitjançant una Representació Intermèdia Algebraica Estesa (eAIR). La primera contribució presenta un mètode d’acumulació ponderada per implementar comparacions binàries estrictes en R1CS. Els enfocaments tradicionals generen un gran nombre de restriccions a causa de la manca d’operacions natives de comparació i de control de flux en el model R1CS, obligant a descomposicions costoses bit a bit i creant colls d’ampolla en el rendiment. El mètode d’acumulació ponderada proposat redueix de manera significativa la sobrecàrrega de restriccions sense comprometre la seguretat o la correcció del sistema, aconseguint millores substancials d’eficiència respecte a l’enfocament lexicogràfic. La segona contribució introdueix el protocol eSTARK, que amplia els STARKs estàndard permetent la gestió concisa de restriccions complexes com ara lookups, permutacions i restriccions de còpia. Aquestes operacions són difícils d’encodear de manera eficient en l’AIR estàndard. El protocol eSTARK integra arguments de compromís vectorial i optimitzacions polinòmiques, oferint un marc flexible i fàcil d’utilitzar per representar una classe més àmplia de càlculs sense introduir sobrecàrrega d’aritmetització innecessària. Totes dues contribucions aborden limitacions pràctiques dels sistemes de proves de coneixement zero actuals, amb la primera centrada en reduir la complexitat de restriccions per a operacions comunes i la segona en expandir l’expressivitat del sistema de proves en si. Conjuntament, demostren la importància de les optimitzacions a nivell d’aritmetització per millorar l’eficiència i la usabilitat de les proves de coneixement zero. (Español) La adopción acelerada de servicios digitales ha puesto de relieve la necesidad de computación con confianza mínima, donde las partes pueden verificar la corrección de los cálculos sin tener que volver a ejecutarlos ni revelar datos sensibles. Los sistemas de pruebas de conocimiento cero, incluyendo SNARKs y STARKs, ofrecen garantías criptográficas de corrección, privacidad y verificabilidad concisa, permitiendo aplicaciones en blockchains escalables, identidad preservando la privacidad y aprendizaje federado verificable. Esta tesis aborda las principales ineficiencias en los sistemas de pruebas ZK basados en restricciones a la capa de aritmetización. La investigación se centra en dos problemas complementarios: optimizar las comparaciones binarias dentro de los Rank-1 Constraint Systems (R1CS) y ampliar la expresividad de los STARKs mediante una Representación Intermedia Algebraica Extendida (eAIR). La primera contribución presenta un método de acumulación ponderada para implementar comparaciones binarias estrictas en R1CS. Los enfoques tradicionales generan un gran número de restricciones debido a la falta de operaciones nativas de comparación y de control de flujo en el modelo R1CS, obligando a descomposiciones costosas bit a bit y creando cuellos de botella en el rendimiento. El método de acumulación ponderada propuesto reduce de manera significativa la sobrecarga de restricciones sin comprometer la seguridad o la corrección del sistema, logrando mejoras sustanciales de eficiencia respecto al enfoque lexicográfico. La segunda contribución introduce el protocolo eSTARK, que amplía los STARKs estándar permitiendo la gestión concisa de restricciones complejas como lookups, permutaciones y restricciones de copia. Estas operaciones son difíciles de codificar de manera eficiente en el AIR estándar. El protocolo eSTARK integra argumentos de compromiso vectorial y optimizaciones polinómicas, ofreciendo un marco flexible y fácil de usar para representar una clase más amplia de cálculos sin introducir sobrecarga de aritmetización innecesaria. Ambas contribuciones abordan limitaciones prácticas de los sistemas de pruebas de conocimiento cero actuales, con la primera centrada en reducir la complejidad de restricciones para operaciones comunes y la segunda en expandir la expresividad del sistema de pruebas en sí. Conjuntamente, demuestran la importancia de las optimizaciones a nivel de aritmetización para mejorar la eficiencia y la usabilidad de las pruebas de conocimiento cero.
Decentralized Finance (DeFi) services are usually constructed by composing a variety of smart contracts. While composability is a key driver of the success of DeFi, it also creates security risks: adversaries may exploit interactions between newly deployed contracts and the pre-existing ones to inflict economic losses. We introduce MEV non-interference, a formal security notion for DeFi composability requiring that the maximal extractable value from a set of newly deployed contracts is not increased by interactions with the existing blockchain state. To support this notion, we define local MEV, a novel measure of economic attacks that focusses on the loss of a given set of victim contracts. We study two adversarial models, with bounded and unbounded wealth, and establish sufficient conditions and locality principles that enable modular reasoning about secure composability. We apply the framework to representative DeFi compositions, including exchanges, AMMs, options, lending pools, routers, and arbitrage contracts, showing how it distinguishes secure compositions from vulnerable ones. Our results provide a formal foundation for reasoning about the economic security of DeFi compositions.
We present Veil, a decentralized messaging protocol that unifies metadata protection, spam prevention, and offline message delivery through a single mechanism: Proof-of-Relay. In Veil, sending a message requires a zero-knowledge proof that the sender has faithfully relayed messages for others through a stratified mixnet. The relay work itself constitutes the anonymizing infrastructure, eliminating the need for cryptocurrency tokens, blockchain consensus, or trusted third parties. We make three contributions. First, we prove that bilateral non-transferable credits with epoch-bound nullifiers achieve incentive compatibility without a global state, a general result applicable beyond messaging to any peer-to-peer system requiring fair exchange. Second, we establish a Growth-Isolation Impossibility theorem showing that no CRDT merge function can simultaneously resist inflation and guarantee completeness for monotonically growing verifiable evidence, and present a resolution via penalty-log CRDTs with locally-computed growth. Third, we prove a constructive adversary bound: any adversary controlling a fraction f of relay nodes necessarily contributes to sender anonymity entropy, while the individual deanonymization probability remains bounded, ensuring that adversarial participation requires a productive contribution while individual targeting remains negligible. Veil requires no economic investment to participate; privacy is earned through device contribution alone. We analyze the protocol's security under a global passive adversary with formal indistinguishability definitions, bound Sybil infiltration under depth-limited social vouching, and demonstrate mobile feasibility with verified constraint counts via Nova folding over BabyJubjub.
Decentralized verifiable credential systems have seen limited deployment in practice. Existing constructions, built on zero-knowledge proofs, are complex, application-specific, and largely restricted to predicates over structured data. We present Privately Inferred Credentials ($π$Creds): privacy-preserving, legacy-compatible, decentralized verifiable credentials generated by trusted LLM inference over authenticated data. LLMs' ability to semantically reason over unstructured data substantially expands the range of claims $π$Creds can certify over existing credential systems. The use of LLMs also introduces new application-level threats, which we formalize through two problems: the Source-Constrained Adversarial Example (SCAE) problem, which captures robustness against adversaries that manipulate authenticated data to obtain misleading credentials, and the Authenticated Covert Predicate Poisoning (ACPP) problem, which captures privacy leakage through adversarial model selection. We characterize applications of $π$Creds over user data, and a novel class of credentials over proprietary software that certifies properties of a service without revealing its source code. Our prototype supports issuing credentials over live financial, health, email, and code sources, and we empirically study the SCAE and ACPP threats on a product expertise credential over real financial data.
Abstract Ethereum's transaction validity model is currently anchored in ECDSA over secp256k1, whose security assumptions weaken in the presence of large-scale quantum adversaries. While NIST-standardized post-quantum signature schemes such as ML-DSA, SLH-DSA, and FALCON provide resistance against quantum attacks, integrating these schemes into Ethereum introduces significant systems-level challenges involving bounded execution, gas determinism, and adversarial verification complexity. This paper introduces PQSigAbstract, a modular post-quantum signature verification architecture for Ethereum that separates validation into a stateless pre-validation phase and a deferred cryptographic verification phase linked through commitment binding. The design defines typed Verification Modules with explicit gas estimation, a versioned Scheme Registry with quarantine-based deployment safety, and a probabilistic aggregation mechanism for non-aggregatable post-quantum schemes. The proposed architecture preserves EU-CMA security while maintaining compatibility with ERC-4337 and RIP-7560 account abstraction models. Formal gas cost models are derived for ML-DSA-44, FALCON-512, and SLH-DSA-128f, and empirical evaluation demonstrates practical deployment feasibility for high-value Ethereum accounts despite substantially higher verification costs relative to ECDSA. Status: Technical Report / Working Paper Author: Ankita Virani Affiliation: University of Colorado Boulder
Adiwena Putra, Cuong Manh Duong, Anh Quang Pham, Joo-Young Kim
Zero-knowledge proofs (ZKP) allows a prover to convince a verifier of computational correctness without revealing private data, ensuring both privacy and verifiability. However, proof generation is highly compute-intensive, dominated by polynomial (POLY) and elliptic-curve (EC) operations. These workloads pose two key challenges for hardware acceleration: (1) efficiently supporting diverse large-precision modular multiplications, and (2) maintaining high utilization across workloads that dynamically shift between POLY and EC stages. Existing reconfigurable accelerators address these issues only partially, remaining limited in precision scalability, algorithmic flexibility, and resource efficiency. To overcome these limitations, we propose ZK-Flex, a flexible and scalable software-hardware co-designed framework for accelerating ZKP proof generation. The software layer incorporates POLY and EC optimizers that reduce computation through hardware- and workload-aware algorithmic choices, while the hardware integrates TCore, a Toom-Cook-based multi-precision core with a flexible NoC and a linked-list memory mechanism that improves parallelism under limited memory capacity. Across representative ZKP benchmarks, ZK-Flex achieves 5 to 11 times speedup and up to 3.8 times higher area efficiency over the state of the art, establishing a new foundation for high-performance, reconfigurable ZKP acceleration.
Many proof-of-stake protocols finance validator rewards from two sources: transaction fees and a finite reserve of tokens. This creates a dynamic hand-off problem. Early in the life of the system, fees may be too small to fund the target level of security; later, fees may become sufficient. The central question is whether the reserve provides enough runway for the protocol to remain secure until this fee-only region is reached. We study this problem in a discrete-time stochastic model of validator participation. Token price and transaction demand fluctuate over time, while validators choose participation strategically. We solve the validator entry game and derive an exact state-dependent reserve threshold, i.e., the minimal reserve stock necessary and sufficient to sustain a target security level. This threshold separates three regions: infeasibility, reserve-dependent security, and fee-only security. Security fails if the reserve first falls below the state-dependent threshold, and a successful hand-off occurs exactly if the fee-only region is reached before that failure time. We derive stress-test guarantees that convert lower confidence bands for token price and demand into reserve requirements, and obtain explicit failure-probability and expected hand-off-time bounds. Finally, we extend the model to forward-looking validators and derive the Markov participation condition that captures how current participation affects future reserve-funded rewards. The main implication is that reserve policy should not be evaluated by nominal depletion dates or steady-state reward ratios alone. A protocol can have a large nominal reserve and still be close to security failure after adverse price or demand shocks. Conversely, once demand crosses the fee-only threshold, the reserve becomes redundant for security. This paper provides a tractable equilibrium framework for stress-testing this transition.
Este Trabajo Fin de Grado presenta un análisis criptográfico y matemático de la arquitectura de Monero, una criptomoneda diseñada con la privacidad como propiedad fundamental de su protocolo. El estudio comienza con la formalización de los fundamentos algebraicos que conforman el sistema, como las curvas de Edwards retorcidas y la completitud de su ley de grupo, característica que contribuye a mitigar vulnerabilidades asociadas a ataques de canal lateral. Sobre esta base se estudia el protocolo Ring Confidential Transactions (RingCT), núcleo de los mecanismos de privacidad de la red. En particular, se analizan las direcciones sigilosas (stealth addresses), que garantizan la no vinculabilidad de los receptores mediante intercambios Diffie–Hellman sobre curvas elípticas; las firmas de anillo CLSAG y las imágenes de clave, que proporcionan anonimato al emisor y previenen el doble gasto; y los compromisos de Pedersen, utilizados para ocultar las cantidades transferidas. Asimismo, se estudian las pruebas de rango Bulletproofs+, destacando su función en la reducción del tamaño de las transacciones mediante argumentos de producto interno. Finalmente, se examinan diversas vulnerabilidades históricas y técnicas de análisis de trazabilidad aplicadas a Monero, evaluando el grado de resistencia que ofrece el protocolo frente a distintos ataques. Los resultados ponen de manifiesto cómo la integración de herramientas avanzadas de criptografía de clave pública, pruebas de conocimiento cero y estructuras algebraicas sobre curvas elípticas permite construir un sistema financiero con garantías de privacidad, seguridad y fungibilidad. ABSTRACT This Bachelor’s Thesis presents a cryptographic and mathematical analysis of the architecture of Monero, a cryptocurrency designed with privacy as a fundamental property of its protocol. The study begins with the formalization of the algebraic foundations underlying the system, including twisted Edwards curves and the completeness of their group law, a feature that helps mitigate vulnerabilities associated with side-channel attacks. Building upon this mathematical framework, the Ring Confidential Transactions (RingCT) protocol, which forms the core of Monero’s privacy mechanisms, is examined. In particular, the thesis analyzes stealth addresses, which ensure receiver unlinkability through Diffie–Hellman key exchanges over elliptic curves; CLSAG ring signatures and key images, which provide sender anonymity and prevent double-spending; and Pedersen commitments, which are used to conceal transferred amounts. Furthermore, Bulletproofs+ range proofs are studied, highlighting their role in reducing transaction size through efficient inner-product arguments. Finally, several historical vulnerabilities and traceability analysis techniques applied to Monero are reviewed in order to evaluate the protocol’s resistance against different types of attacks. The results demonstrate how the integration of advanced public-key cryptography, zero-knowledge proofs, and algebraic structures based on elliptic curves makes it possible to build a financial system with strong guarantees of privacy, security, and fungibility.
Federated Learning (FL) is increasingly deployed in healthcare to enable collaborative intelligence while keeping sensitive data privately at local institutions. However, existing healthcare-oriented FL frameworks still suffer from several limitations: they are vulnerable to adversarial model updates, provide limited transparency and verifiable auditability, and often lack predictable performance under constrained resources. We present IIN-Health, a blockchain-enhanced intelligent fusion network tailored for dependable healthcare FL. IIN-Health adopts a dual-chain architecture with policy-aware access control and auditable provenance tracking to integrate learning, security, and governance in a unified framework. Evidence-Carrying Access Tokens (ECATs), combined with zero-knowledge proofs, are introduced to enforce patient-defined policies and validate access decisions without disclosing sensitive information. In addition, we design MedBFT-Δ, a domain-specific Byzantine fault-tolerant protocol that ensures reliable system behavior in the presence of faulty or malicious participants. We conduct several experiments to validate its feasibility and accuracy on the MNIST dataset. The results demonstrate that IIN-Health achieves smooth and stable convergence, exhibits strong resilience against poisoning attacks, and maintains graceful performance degradation under resource constraints, while preserving verifiable auditability of model updates and data flows. These observations indicate that IIN-Health can provide a practical balance among performance, security, and regulatory compliance, and thus offers a promising foundation for trustworthy and scalable FL deployments in healthcare.
Jyotiplaban Talukdar, Ferdous Ahmed Barbhuiya, Shouraya Mishra, Shubhashish Shukla
Asset ownership tracking is fundamental to economic activity, yet it remains fragmented across paper-based deeds, centralised registries, and siloed databases. Public blockchains provide immutability but suffer from scalability limitations and inflexible consensus mechanisms unsuitable for enterprise deployment. We present Keychain Signet (KCS), a decentralised architecture designed as a notarised asset ledger that strictly separates application logic, consensus, and persistence. KCS distributes responsibilities: service providers manage application workflows, notaries enforce validity and uniqueness via BLS signatures, and storage nodes execute BFT-Raft consensus to order blocks. This architecture enforces a "notarised append" model where authorised writes are persisted and ordered by the storage cluster. Unlike standard blockchains, our architecture resolves the latest asset state in O(1) time via a disc-backed Distributed Hash Table while maintaining an immutable, cryptographically linked history for auditability. Experimental evaluation demonstrates 401.1 TPS throughput, notary signing latency of 1.6–10.2 ms scaling linearly with committee size, signature verification under 0.81 ms, and storage persistence under 700μs. The system tolerates Byzantine faults, storage corruption, and node crashes while preserving safety and liveness guarantees.
Oblivious Transfer (OT) is a fundamental cryptographic primitive enabling privacy-preserving computation and constitutes a core building block for secure multi-party computation while supporting a wide range of security-sensitive applications: private information retrieval, zero-knowledge proofs, and password-authenticated key exchange, to cite a few. While recent advances in OT extension have significantly reduced amortised costs, their reliance on batches of random base OTs and substantial pre-computation phases limits their practicality in scenarios where the number of transfers is modest or where communication latency and client-side computation are critical constraints. In such settings, efficient base OT protocols remain both relevant and necessary. In this work, we introduce $I$-$(OT)^2$, a novel base 1-out-of-2 OT protocol grounded in the quadratic residuosity problem, specifically designed to minimise receiver-side computation and interaction. Our construction is particularly appealing on client--server architectures in which the receiver operates on low-power hardware, such as Internet of Things (IoT) devices. Through a lightweight offline pre-computation phase, $I$-$(OT)^2$ shifts the on-transfer computational burden almost entirely to the Sender, while reducing online communication to only six messages and four digests exchanged. We provide a detailed description of the protocol, accompanied by a formal proof of its security. Moreover, to demonstrate the viability of $I$-$(OT)^2$, we also present an open-source proof-of-concept implementation (in C language) evaluated on real IoT hardware. Results are staggering: for 128-bit security using a 3072-bit RSA modulus, the receiver incurs an average online cost per OT as low as 2.80 μs on desktop platforms and 39.90 μs on IoT devices, more than 10$\times$ faster than the well known SimplestOT.
Shor's algorithm represents the main threat of quantum computers to cryptography. In order to precisely understand its feasibility, many authors have worked towards reducing its costs, either at the logical level (assuming a fault-tolerant architecture), or at the physical level (taking into account the constraints of envisioned hardware). In particular, recent works by Chevignard et al. (CRYPTO 2024) and Gidney (arXiv 2025) used improved arithmetic to significantly reduce the qubit cost of factoring RSA public keys. Even more recently, Babbush et al. (arXiv 2026) improved the cost of computing elliptic curve discrete logarithms, with a reduction of a factor 2 to 3 in gate count and qubit count compared to a previous work by Litinski (arXiv 2023). Their result relies on optimized point addition circuits on elliptic curves over prime fields. However they did not reveal their logical quantum circuits, relying instead on a zero-knowledge proof. In this paper, we detail a quantum logical circuit architecture which gives similar results as Babbush et al., with a slightly higher number of qubits (around 1.5% increase) and a slightly smaller Toffoli gate count (between 6.5% and 10% reduction) for the curve secp256k1. We also give gate counts for a generic variant of the circuit, which is valid for any prime field.
Background and Gap Information: Positive, negative and hybrid external confirmation processes are the pillars of audit evidence as posed in the standard ISA 505, however the response rate is very low 48-72%, fraud is not detected 12-38% and there is an unresolvable conflict between assurance and data privacy. This “auditor’s dilemma” intensifies with cross-border transactions and tight data privacy regulations such as Iraq’s Personal Data Protection Law No. 10 of 2024. Although there are recent proposals based on blockchain or homomorphic encryption, none of them has presented a mathematically zero-knowledge, empirically verified, and regulatorily compliant confirmation protocol that seamlessly performs over heterogeneous ERP systems without leaking its underlying commercial data. Objective: We present the Decentralized Confirmation Matrix (DCM) - a game-changing evidence of audit protocol based on zero-knowledge succinct non-interactive arguments of knowledge (zk-SNARKs) to cryptographically prove a set of external transactions, while leaking only the fact that they are consistent (“valid/invalid”) together with a timestamp. The paper (1) details the DCM design, including its novel dual-nullifier and heterogeneous trust models; (2) presents an empirical comparison of DCM with traditional techniques based on authentic Iraqi state-owned enterprise (SOE) data; (3) scrutinizes DCM against Iraqi higher educational certification standards and Scopus Q1 repeatability requirements; and (4) delivers an open-source route-to-implementation (ZKCaaS). Methodology: We developed a complete DCM prototype using Circom 2.1.6 and SnarkJS over a permissioned blockchain sandbox (Iraqi National Blockchain Sandbox). 4We acquired genuine transaction logs (n=25,000+ confirmations) from three Iraqi SOEs: Northern Refineries Company (Baghdad), Basra Oil Terminal (Basra), and Iraqi Telecommunications Company (Erbil).A controlled field experiment with 45 Iraqi auditors (repeated measures, counterbalanced) was conducted to evaluate DCM vis-a-vis traditional positive and email-hybrid confirmations on response time, error rates, cost, auditor satisfaction (UTAUT2), and attack resilience. Results: DCM reduced average confirmation response time by 99.6% (to 0.05 days), attained a 100% response rate by automation, elevated fraud detection from traditional 62% to 97%, and brought in cost per confirmation (from 6% to 0.45%). Auditor satisfaction rated 4.6/5, and the dual‑nullifier scheme prevented 100% of replay and collusion attacks - a guarantee not found in any prior work. Audit risk (ISA 315) decreased by 93% (from 6% to 0.45%).Cross‑platform rollup between SAP and Oracle succeeded at 98%, solving a long‑standing interoperability ga. Conclusion: DCM is the first practical, privacy-preserving, and empirically superior external consistency checking protocol that satisfies ISA 500/505 while enabling “cryptographically sealed evidence” as a novel evidence type. The article is in line with the quality requirements of the Iraqi accreditation agency as well as Scopus Q1, which consider theoretical novelty, empirical rigour and open‑source replicability. We propose a strategic vision for 2025-2030 and an Autonomous Audit Agent (AAA) for full automation.
In the Internet of Vehicles (IoV), the large-scale deployment of smart vehicles has triggered new road traffic safety challenges. Particularly, existing vehicle accident report transmission schemes still face challenges such as privacy leakage, Single Point of Failure(SPOF), physical cloning attacks, and excessive computational overhead. To address these issues, this paper proposes a secure accident report transmission scheme that uses Non-Interactive Zero-Knowledge Proof (NIZKP) and Physically Unclonable Functions (PUF). This paper designs a decentralized authentication scheme for vehicle registration that prevents SPOF and privacy leakage. We also use the PUF to realize two-factor authentication login, which effectively resists physical cloning attacks. In addition, the authentication process uses NIZKP based on the Pedersen commitment to realize authentication for accident report coordination. At the end of the accident report coordination, it is passed into the blockchain for storage, realizing the secure transmission of accident reports. To reduce the storage as well as computation overhead, this paper uses a key derivation function to update the key. Finally, formal security analysis was conducted using the Real or Random (ROR) model and the ProVerif tool, the results prove that the proposed protocol meets security requirements. Comparing our proposed scheme with related schemes, the computational overhead of our V2V scheme is reduced by 42.4%, with higher security and lower communication overhead.
Open access
Vehicular Ad Hoc Networks (VANETs)
Physical Unclonable Functions (PUFs) and Hardware Security
Ch Sree Kumar, Jatindra Kumar Dash, K. Hemant Kumar Reddy
Blockchain-enabled healthcare infrastructures demand latency-aware, privacy-preserving, and scalable transaction management due to the stochastic and high-volume nature of clinical data processing in decentralized environments. In this study, we propose a blockchain-aware Modified M/M/C (Mo M/M/C) queueing framework specifically designed for NFT-enabled healthcare systems integrated with Zero-Knowledge Proof (ZKP)-based verification. Unlike classical queueing models that assume single-stage service, the proposed model incorporates a multi-stage transaction pipeline consisting of medical processing, NFT tokenization, ZKP verification, and blockchain validation. Accordingly, an effective service rate formulation and blockchain-adjusted arrival rate are analytically derived to capture cryptographic overhead, consensus latency, and smart contract execution delays within a unified stochastic framework. Patient records, prescriptions, and diagnostic data are securely encapsulated as NFTs to ensure immutability, traceability, and decentralized ownership, while ZKP protocols enable privacy-preserving authentication without exposing sensitive medical information. The model further integrates dynamic priority-aware scheduling and validation-aware utilization to optimize resource allocation under heterogeneous healthcare workloads. Extensive discrete-event simulations conducted over scalable transaction volumes (1,000–100,000) evaluate key performance metrics including throughput, average waiting time, system response time, and latency. The results demonstrate that the proposed Mo M/M/C framework significantly improves queue stability, reduces congestion, and enhances throughput compared to FIFO, LIFO, SIRO, and standard M/M/C models. Overall, the revised framework provides a mathematically grounded, cryptography-aware, and blockchain-consistent solution for secure and real-time healthcare transaction management
By chance or by destiny, Bitcoin mining companies have found themselves with a golden opportunity in their hands: they possess the most scarce asset of the 21st century—energy. Something similar happened back in the mid-19th century, railroad companies acquired millions of acres of land and rights-of-way strictly to lay down train tracks with the main idea of a business fundamentally focused on physical transportation. However, when the telegraph was invented, they realized that the optimal location to deploy electrical communication lines was right alongside those very train tracks. They already possessed the cleared terrain, the physical security, and the legal rights-of-way. And as we have seen, the structural mispricing identified in this thesis represents a finite, high-velocity arbitrage window. Where currently, Wall Street's evaluation models remain anchored to old crypto-mining frameworks, valuing these entities on cyclical hash-rate economics rather than the long-duration infrastructure value of their underlying energized grid connections.
Foundational agent interoperability standards, notably the Agent-to-Agent (A2A) protocol and the Model Context Protocol (MCP), have advanced multi-agent system communication, and complementary identity frameworks leveraging W3C Decentralised Identifiers (DIDs) and Verifiable Credentials (VCs) provide cryptographic agent authentication. However, no existing protocol supports content-based semantic routing of agent payloads across organisational trust boundaries without requiring the routing intermediary to decrypt the payload, which is a hard constraint in compliance-sensitive environments governed by GDPR, HIPAA, and MiFID II. We propose SS-ZKR, a three-mechanism privacy-preserving routing protocol designed as a complementary layer atop A2A/MCP. Mechanism I introduces blind routing via differentially private semantic intent vectors cryptographically bound to zero-knowledge proofs of payload-schema consistency. Mechanism II offers vector-weighted adaptive payload sanitisation with formal (epsilon, delta)-differential privacy for numerical fields and heuristic semantic aggregation for textual fields. Mechanism III presents a spatial-to-cryptographic policy compiler that translates visually defined trust-zone topologies into deterministic zero-knowledge access circuits. We provide a formal threat model, analyse information leakage bounds of intent vectors, present pseudocode for all three mechanisms, and give analytical complexity comparisons against TEE-based and homomorphic encryption-based routing baselines. SS-ZKR lets enterprises in financial services, healthcare, and defence orchestrate heterogeneous AI agents across regulatory boundaries without exposing proprietary data to routing infrastructure.
Quantum computing poses significant challenges to traditional zero-knowledge proof schemes based on number-theoretic assumptions. As a result, code-based cryptography has attracted increasing attention for its resistance against quantum computing. In this paper, we study the Rank Syndrome Decoding problem (RSD) and investigate its ZK proof formulation within the MPC-in-the-Head framework. To prove the possession of a secret witness, we reformulate the secret witness as a mixed-field matrix multiplication preserving the rank constraint, and then obtain a representation that aligns naturally with the local-view paradigm of MPC-in-the-Head. Utilizing this value-to-calculation technique, we introduce the RSD relation into a ZKBoo-style (2, 3)-secret-sharing MPC-in-the-Head framework and obtain an RSD-based zero-knowledge proof scheme via mixed-field secret sharing. The resulting scheme reduces the proof size relative to generic formulations while preserving completeness, soundness, and zero-knowledge for the interactive protocol. The Fiat–Shamir non-interactive extension is analyzed only in the classical random oracle model; we do not claim QROM security for this variant.
Abstract As AI agents evolve into autonomous economic actors, verifiable and legally binding identity frameworks become critical. This paper presents Ricardian-TEA , a novel architecture combining Triple-Entry Accounting (TEA), Ricardian Contracts, and Distributed Ledger Technology to assign “Legal-Technical Identities” to AI agents. We provide rigorous mathematical foundations: a Ricardian-TEA Integrity Theorem proving that constraint enforcement, non-disputability, and identity binding hold with overwhelming probability under standard cryptographic assumptions, and a Cyber-Chama Convergence Proposition characterising reputation-based trust dynamics. The framework ensures GDPR compliance via Zero-Knowledge Architecture and Crypto-Shredding. Proof-of-concept implementations on Ethereum Sepolia and Bitcoin SV testnets demonstrate chain-agnostic applicability, achieving at worst 1.4 s latency per transaction while maintaining 100% auditability of AI transactions.