Given that digital governance has achieved extensive spread and people rely increasingly on online services, affordable and trustworthy identity management is now one of the core pillars of contemporary e-Governance systems. Conventional identity systems are usually centralized, highly susceptible to cyber-attacks and most likely to breach privacy. Blockchain technology provides a decentralized, tamper-proof, and transparent system, which guarantees data integrity, data security, and the privacy of the user. In this paper, the authors research the adoption of blockchain-based identity management within e-Governance sites. We discuss available solutions, assess the risks along with their weaknesses and strengths, and suggest a design on how to introduce a safe blockchain-based identity system. Important efforts have been on developing a holistic system that brings smart contract, cryptographic protocols and distributed ledger technologies together to make citizen identification and authentication secure. The outcome of the results shows enhanced security, less identity fraud, and better data security, so there is a possibility of scalability and resilient e-Governance applications.
Shihab Sarar, Ali Imran Mehedi, Fabbiha Tahsin Prova, Saha Reno
The modern metropolis essentially demands the use of stateâofâtheâart, realâtime surveillance systems, which should be reliable, scalable, and respectful of privacy at the same time. Critical shortcomings in traditional architectures are single points of failure, poor scalability, frequent data breaches, and inadequately managed privacy. These aspects of themselves make it inept for the demands of dynamic, fastâpaced city environments, without which reliability, security, and adaptability cannot be compromised at any cost. This brings to light the critical need for innovative and decentralized solutions that can overcome these challenges comprehensively. In our proposed approach, a decentralized framework integrates private blockchain technology via Ethereum, a hybrid cryptography model combining advanced encryption standard (AES) and RivestâShamirâAdleman (RSA) encryption, and stateâofâtheâart deep learning techniques such as YOLOv8, DeepSort, and ArcFace. Blockchain technology ensures metadata is immutable and transparent, thus saving metadata from unauthorized access and tampering. The hybrid cryptography model encrypts sensitive data through AES and securely shares the key of AES through RSA encryption, while decryption is efficiently done in a key management system (KMS). Furthermore, YOLOv8 and DeepSort can be used for highâprecision object detection and realâtime tracking, and ArcFace can be used for facial recognition, meeting the splitâsecond decisionâmaking required in urban surveillance. Extensive experiments are performed, and the results indicate that the proposed framework enhances detection precision, tracking accuracy, realâtime responsiveness (60 FPS), and resistance to tampering (>99% chain quality per quorum Byzantine fault tolerance [QBFT]) without compromising efficiency. The adaptive and reliable solution meets modern urban surveillance demands that are evolving at an everâincreasing pace. The scalability of the operation further ensures enhanced public safety. This paper discusses a decentralized urban surveillance system that is both tamperâproof and secure using current blockchain technologies, InterPlanetary file system (IPFS), hybrid AESâRSA, and deep learning technologies to mitigate the risks of a traditional centralized system, such as data tampering and privacy violations. The system uses the Ethereum blockchain to provide immutable metadata, the IPFS protocol to create a fully distributed storage system of video and image frames, and an offâchain KMS service to distribute the keys to the authorized edge devices. The system utilizes realâtime object detection (YOLOv8), tracking (DeepSort), and face recognition (ArcFace) to perform inference locally on the edge devices. We have performed experiments that demonstrate the tamperâproof and secure scalability with low latency and secure tamperâproof data integrity of this urban surveillance system in everâchanging urban environments.
Doaa I. Hasan, Mustafa Hamid Abd Alsadh, Hayder Makki Shakir, Hamsa Emad Mahmood ¡ 7 authors
This is the newest technique to make sure that smart contracts are always secure in very important domains, like world banking. Quantum computers canât break blockchain rules, hence this is conceivable. The major purpose of this research is to see whether post-quantum cryptography can be combined with blockchain technology to make it safer to move money across borders. Quantum computers might easily get into older blockchain systems since they employ well-known encryption methods like ECC and RSA. This makes it easy for other people to hurt them. As quantum computing becomes more common, the safety of smart contracts used in international banking is becoming more and more at danger. We think that the Lattice-Based Cryptographic Integration Framework (LBCIF) might help with these issues. This system leverages lattice-based post-quantum algorithms like Kyber and Dilithium. These algorithms may keep cryptography safe against quantum assaults. You can use these algorithms to sign smart contracts, prove who you are, and agree on blockchains. The LBCIF is an excellent instrument for trade finance since it uses smart contracts to make settlements and letters of credit with banks all around the world automatic. The framework ensures secure key exchange, digital signature validation, and interoperable transactions across regulatory environments. Findings show that LBCIF maintains performance while significantly improving resistance to quantum threats. It enables secure, scalable, and regulation-compliant smart contract execution for global financial operations.
Traditional digital trust architectures suffer from the âLibrary Problemâ: dependency on pre-compiled, static lookup tables or binaries that must be trusted blindly, creating supply-chain vulnerabilities. This paper proposes a paradigm shift to Intrinsic Trust, where encoding infrastructure is mathematically regenerated at runtime rather than distributed. We introduce the 0MXI Calculus, a deterministic lattice system anchored on universal transcendental constants:the golden ratio ÎŚ â 1.618033988749895 and Ď â 3.141592653589793, with a contraction ratio Îť â 0.339949771344778. Operations on a quantized F15 lattice ensure cross-platform determinism, bounded by a Prime Boundary Horizon (N = 23) that guarantees injective reversibility (Theorems 1 and 2).This framework underpins TreeOS, an operating system that bootstraps from a âMath Root-of-Trustâ via autogenesis, regenerating a bijective Tick Table for byte encoding without stored dependencies. TreeBABEL, the verifiable data transport protocol, packages data as JSON artifacts with mathematical manifests for independent receiver validation. Extending this, the VMEM Node Architecture transforms online repositories into externalized memory banks, enabling AI models to scrape and derive OS state on demand, eliminating internal weight bloat and static knowledge cutoffs.We demonstrate adaptability to constrained ledgers (e.g., 280-character limits) for efficient chunking. Through rigorous proofs and a Python reference implementation, we show that trust can be calculated, not stored, decoupling systems from physical hardware and fostering entropy-neutral, zero-trust computation.
We present FADP (the Fluid Agentic Payment Protocol), an HTTP-native twophase protocol for secure DeFi agent-to-agent transactions and agentic payments that couples on-chain transactions with cryptographic identity attestation in a single round-trip. Every FADP identity proof is unique per agent, unforgeable under standard cryptographic assumptions, and unreplayable by construction via four-dimensional nonce protection â making it the first HTTP payment protocol with formal guarantees on all three properties simultaneously. FADP extends RFC 7231's HTTP 402 status code [1] with three header namespaces â X-FADP-* for payment challenge and proof, XPauli-* for zero-knowledge identity binding [2], and X-FLDP-* for ECDSA request signing â yielding a wire format in which the server can verify who placed an order, that the request is fresh, and that the payment is on-chain final, all from headers alone. The protocol operates in a strict two-phase model: Phase Îą (initialization) provisions seven keys across three categories (local private, server public, internal proving), and Phase β (runtime) executes the 402 â onchain settlement â 200 cycle. Private keys never cross the network at any phase; the server holds only public material; the chain is the source of truth for payment finality. We prove four theorems â protocol correctness, liveness independence, replay impossibility, and identity-payment binding â and introduce three new metrics for HTTP-native payment protocols: Authentication Round-Trip Count (ART), Payment Atomicity Score (PAS), and Sovereignty Inheritance (SI). The reference implementation is deployed on Base Mainnet as a beta MVP prototype and submitted to the IETF as draft-fluid-fadp-01. Median end-to-end cycle latency is ~160â215 ms (analytical from measured components: 2 RTT plus on-chain confirmation), and per-call cost is approximately $0.001â$0.01 in stablecoin payment. To our knowledge, FADP is the first published HTTP payment protocol that (i) couples payment with cryptographic identity attestation in a single response, (ii) operates entirely within the existing RFC 7231 status-code framework with no L4 or L3 modifications, and (iii) inherits strict self-custody guarantees (ÎŁ = 5) from a companion identity standard.
Zuodong Wu, Dawei Zhang, Mianxiong Dong, Kaoru Ota
In the data-driven era, the unchecked collection and processing of personal data has given rise to serious privacy concerns. In response, the General Data Protection Regulation (GDPR) was introduced to grant individuals stronger control over the use of their data. Privacy data retrieval methods show considerable promise in this context, but further improvements are required to balance the principles of lawfulness and data minimization. To address this problem, we propose PDRAA, an efficient privacy data retrieval protocol with anonymous authorization based on the verifiable credential (VC). Specifically, our designed VC achieves anonymous identification of data subjects and facilitates fine-grained access control by supporting selective disclosure of attributes. By combining VC with non-interactive zero-knowledge (NIZK) proofs, PDRAA enables data subjects to anonymously authenticate via VC presentation. This allows the data controller to verify the legitimacy of retrieval requests while ensuring compliance with the principle of data minimization. Besides, PDRAA introduces a re-randomization mechanism to prevent linkability attacks during the authorization process and provides lightweight, flexible authorization revocation. Moreover, we utilize Labeled Private Set Intersection (Labeled PSI) technology to meet the privacy requirements of participants and support batch retrieval. Our protocol takes a comprehensive security analysis within the Universal Composability framework. Experimental results demonstrate that PDRAA outperforms existing methods in terms of performance, which is significant for promoting compliance with GDPR.
Mohammad Badhesha, Arun Sekar Rajasekaran, Ashok Kumar Das, Azees Maria ¡ 6 authors
Authenticated key exchange and secure handover between vehicles and roadside units (RSUs) are essential for the reliability of vehicular networks. However, many existing approaches incur high computational and communication overhead or rely on re-authentication, which limits scalability under high mobility. Moreover, conventional schemes based on classical cryptography cannot withstand quantum adversaries, while lattice-based solutions overlook the need for efficient handover and strong privacy protection. To address these limitations, a lattice-based authentication and key agreement protocol that integrates non-interactive zero-knowledge (NIZK) proofs to enable seamless and post-quantum secure handover in both intra-domain and cross-domain vehicular networks (LAKAS-N) is proposed in this work. The scheme establishes mutual key exchange between vehicles and RSUs, eliminates re-authentication within a single domain, and preserves anonymity when transitioning across domains. Security is rigorously validated through informal and formal analyses, including Scyther-based verification, which confirms resistance against classical and quantum attacks. Lastly, a comprehensive evaluation shows that LAKAS-N achieves stronger security with substantially lower computational, communication, storage, and energy costs compared to state-of-the-art protocols, demonstrating its practicality for real-world vehicular networks.
Bitcoin solved the double-spend problem. The security model is sound. The computation produces no output beyond the security it purchases. SHA-256 hashing generates heat and irreversible work, both of which are discarded the moment a block is verified. The network accumulates ledger entries. It accumulates nothing else.
Vehicular Ad Hoc Networks (VANETs), as the core infrastructure of intelligent transportation systems, face critical security challenges such as privacy leakage and difficulties in tracing malicious behavior due to open wireless channels and high node mobility. While blockchain-based identity authentication offers inherent advantages like decentralization, making it suitable for the distributed networking scenarios of VANETs, current solutions still suffer from notable shortcomings, including a lack of compliance with the SM9 standard and insufficient regulatory oversight. To resolve the fundamental tension between vehicle identity privacy protection and regulatory traceability in VANETs, this paper proposes an efficient SM9-ABS vehicle identity authentication scheme on blockchain for VANETs. By optimizing SM9 parameters, the scheme integrates Attribute-Based Signature (ABS) and Zero-Knowledge Succinct Non-Interactive Argument of Knowledge (zk-SNARKs) primitives to construct an efficient fine-grained attribute signature generation and verification algorithm, ensuring both security and computational efficiency. An SM9-based threshold identity tracing mechanism is designed to prevent single-point authority abuse, achieving privacy-preserving authentication with controllable accountability. Finally, a complete formal security proof is provided under the q-Strong Diffie-Hellman (q-SDH) hardness assumption, and comparative experiments demonstrate the superior comprehensive performance of the proposed scheme.
Junhee LEE, Yixi Cai Lili lei Lei Li, Gweonho Jeong, Jihye Kim ¡ 6 authors
Forward-secure digital signatures protect the integrity of past signatures, even if the current signing key is compromised. Among forward-secure signature schemes, the method introduced by Lee et al. [1], based on zero-knowledge succinct non-interactive arguments of knowledge (zk-SNARKs), is particularly notable for achieving constant complexity across all metrics without requiring a predefined maximum time period. However, a naive approach to recursive proof composition results in an excessive amount of redundant computation being repeated for each signing process, which our method reduces significantly. In this paper, we advance a zk-SNARK-based forward-secure signature scheme by significantly improving the efficiency of its signing algorithm. By incorporating commit-and-prove SNARKs, we replace the inner verification process with commit verification within the signing circuit. Furthermore, we employ efficient recursive zk-SNARKs with accumulation and folding schemes to improve the setup and update algorithms. Our implementation demonstrates the practicality of our approach: the signing procedure completes in 0.18 seconds, achieving a 75-fold speedup over the previous scheme, setup time is reduced to 0.71 seconds - over 61 times faster, and public parameters are reduced to 25 MB, more than 16 times smaller.
Andreu Pere Isern-DeyĂ , M. Francisca Hinarejos, Josep LluĂs Ferrer Gomila
Online transactions are becoming increasingly popular, and the purchase and delivery of digital assets is a prominent example. In these transactions, buyers are hesitant to pay for an asset until they receive it, whereas sellers are reluctant to send the asset until they are paid. Unfortunately, actual solutions do not always meet all the requirements to conduct a secure exchange, with fairness being one of the requirements that needs more attention. Historically, solutions to this problem have relied on trusted third parties (TTPs) serving as trusted intermediaries among participants, but the advent of blockchain has enabled the reduction or elimination of TTP involvement in many cases. In this paper, we present a fair blockchain-based solution that does not require any TTP for the secure delivery of digital assets, proving its technical feasibility and cost-effectiveness through assessments on blockchains based on the Ethereum Virtual Machine.
A protocol-level transaction tax faces a structural privacy tradeoff: jurisdictional attribution requires releasing aggregates from which an adversary with auxiliary information may attempt to learn properties of the underlying transactions. This paper formalizes the tradeoff and proves two mechanism-level theorems. Theorem 1 establishes that the composition of Pedersen commitments with zero-knowledge validity proofs preserves individual-transaction hiding under standard cryptographic assumptions, with no distributional requirement on transaction amounts. Theorem 2 separates two cohortaggregation threats that prior analyses have conflated and bounds each. Theorem 2a (event detection): against an adversary attempting to detect that an anomalous transaction of magnitude đ occurred in a cohort of size đ, the optimal likelihood-ratio-test.
This paper presents the post-quantum integrity architecture designed and being implemented within Smart Astro among the rst known platforms delivering Deterministic Engine Computed, AI-Narrated, Blockchain-Veried life guidance at scale. Smart Astro operates across 18 active life-decision intents and over 40 auspicious-timing categories, serving users globally through a real-time, pay-per-question model. Classical asymmetric cryptography underpinning current blockchain infrastructure is vulnerable to Shor's algorithm on fault-tolerant quantum computers. Smart Astro addresses this proactively by integrating NIST-standardised post-quantum cryptographic primitives FIPS 203 (ML-KEM), FIPS 204 (ML-DSA), and FIPS 205 (SLH-DSA) alongside a Solana-anchored proof chain already live in production. The central architectural contribution is a layered separation of concerns: the deterministic engine computes a structured, repeatable output; cryptographic proof generation runs asynchronously outside the delivery path; the AI narration layer is isolated from the proof chain; and only a commitment hash is written to the Solana ledger, with the full postquantum signature bundle stored o-chain. Every paid answer carries an independently veriable SA-PROOF identier with zero personally identiable information (PII) on-chain. A hybrid ML-DSA + SLH-DSA signature scheme provides defence in depth against both lattice cryptanalysis and harvest-now-decrypt-later adversaries. This architecture establishes a replicable standard for cryptographic integrity in AI-narrated deterministic knowledge systems.
This paper presents the post-quantum integrity architecture designed and being implemented within Smart Astro among the rst known platforms delivering Deterministic Engine Computed, AI-Narrated, Blockchain-Veried life guidance at scale. Smart Astro operates across 18 active life-decision intents and over 40 auspicious-timing categories, serving users globally through a real-time, pay-per-question model. Classical asymmetric cryptography underpinning current blockchain infrastructure is vulnerable to Shor's algorithm on fault-tolerant quantum computers. Smart Astro addresses this proactively by integrating NIST-standardised post-quantum cryptographic primitives FIPS 203 (ML-KEM), FIPS 204 (ML-DSA), and FIPS 205 (SLH-DSA) alongside a Solana-anchored proof chain already live in production. The central architectural contribution is a layered separation of concerns: the deterministic engine computes a structured, repeatable output; cryptographic proof generation runs asynchronously outside the delivery path; the AI narration layer is isolated from the proof chain; and only a commitment hash is written to the Solana ledger, with the full postquantum signature bundle stored o-chain. Every paid answer carries an independently veriable SA-PROOF identier with zero personally identiable information (PII) on-chain. A hybrid ML-DSA + SLH-DSA signature scheme provides defence in depth against both lattice cryptanalysis and harvest-now-decrypt-later adversaries. This architecture establishes a replicable standard for cryptographic integrity in AI-narrated deterministic knowledge systems.
Open access
Cryptography and Data Security
Cryptographic Implementations and Security
Physical Unclonable Functions (PUFs) and Hardware Security
This chapter starts at the foundationâthe problem blockchain is actually built to solve. Before any protocol detail makes sense, you need to understand why trust breaks down across a network of strangers, why decades of serious attempts at digital cash kept failing at the same point, and how Bitcoinâs combination of proof-of-work and a longest-chain rule finally closed the gap. The Byzantine Generals Problem is not a historical footnote here; it is the precise shape of the consensus challenge that every distributed ledger must answer. By the end of this chapter, you will have covered: