Blockchain Papers

Vikas Reddy Mandadhi

No abstract is available for this record.

Yoav Cohen

Decentralized applications often require reliable information about external events whose outcomes are uncertain at the time of reporting but verifiable after settlement. Existing oracle mechanisms typically rely on trusted data providers, token-weighted voting, staking, dispute games, or prediction-market incentives. These approaches may allocate influence according to wealth, identity count, or discrete votes rather than calibrated informational quality. This paper introduces Proof of Market Consistency (PoMC), an information-weighted oracle mechanism for decentralized event resolution. Admitted reporters submit probabilistic forecasts about event outcomes. Reports are evaluated ex post using strictly proper scoring rules, and each reporter accumulates information capital through a multiplicative update rule based on predictive performance. Oracle outputs are obtained by aggregating reports with information-capital weights. We establish four main properties. First, strictly proper scoring rules provide one-shot incentives for truthful probabilistic reporting. Second, under stationary reporting performance, information capital concentrates on the most accurate reporters while uninformative reporters lose influence. Third, the update rule admits an online-learning interpretation and yields a sublinear regret bound relative to the best reporter in hindsight. Fourth, because purely reputation-based systems are vulnerable to Sybil attacks, we introduce a minimal stake-gated admission rule that bounds identity creation while leaving oracle influence determined by predictive accuracy. PoMC is not a replacement for block-level consensus protocols. Rather, it is a properscoring and online-learning layer for decentralized oracle resolution. The mechanism separates economic admission from informational authority: stake limits identity creation, while calibrated predictive performance determines influence.

Balram P, Lakshmi Rai, Mansi Kodag

ZKVault is a privacy-preserving decentralized KYC system aimed at eliminating redundant identity verification and reducing the risks associated with centralized data storage. The project leverages zero-knowledge proofs and blockchain technology to enable users to prove specific identity attributes without exposing sensitive personal information. It ensures secure, tamper-proof, and reusable verification across multiple platforms while maintaining user privacy and regulatory compliance. Experimental results demonstrate efficient performance, with proof generation taking approximately 1.8 seconds and verification under 50 milliseconds, making ZKVault a scalable and practical alternative to traditional KYC systems.

Saurabh Jain, Adarsh Kumar

No abstract is available for this record.

Hugo Hedlund

A majority of well-known blockchains supports Non-Fungible Tokens (NFTs) operations via smartcontracts. Smart contracts often allow users to store arbitrary logic and code for a small programon the blockchain, and run it on the validator nodes when a monetary transaction is made to thecontract’s account. The use of smart contracts creates extra complexity in the blockchain protocolwhen allowing concurrent smart contract execution between shards alongside monetary transactions.To reduce the complexity of the blockchain protocol, native tokens and operations could be supportedby the blockchain, albeit restricting developers to a predefined set of functions and operations. Nativetoken operations can serve as a secure complement to the versatility of Turing-complete smartcontracts, providing robust, predefined primitives that could reduce the surface area for smart contractvulnerabilities. This project introduces a native token model that is centered on unique, non-fungible tokens thatsupport three primary use cases: ownership, rights and authenticity. By requiring bilateral transferconsent, and supporting optional clawback and freeze mechanisms, for revocable rights and non-transferable tokens respectively, the model bridges the gap between blockchains and legal frameworks.Additionally, an indirect transaction cost mechanism is implemented to protect the blockchain networkagainst Denial-of-Service attack during non-monetary operations. The project is supported by an emulator implementing monetary and token operations, alongsidea implementation design of how the token protocol could be integrated within ScaleGraph. The emulator’s throughput displays a slightly degraded performance of token transfer operations of ~150TX/s on average, compared to monetary transfers in the current implementation. Despite this, theemulator maintains a high average throughput of ~1300 TX/s with load generators of both monetaryand token transfer operations, when tested on a VPS with 2 vCPUs and 4GB of ram.If the token operation properties and performance compared to monetary transaction are transferableto ScaleGraph, native tokens could be a preferred way of implementation of tokens independentlywether or not with implementation of smart contracts.

Masaru Kasai

This paper introduces DNET (Dual Network Exchange Technology), an interface architecture that unifies Settlement, Exchange, and Record generation into a single transaction structure for digital payments. Modern payment systems often treat exchange and settlement as separate backend processes, leading to fragmented identifiers, inconsistent idempotency behavior, and operational divergence across implementations. DNET resolves these issues by binding Payment Intent, Exchange Decision, and Settlement Outcome under a single TxID, enabling atomic SER‑coupling across Web2 and Web3 environments. The architecture provides a protocol‑level foundation for multi‑asset payments, ensuring traceability, auditability, and interoperability while reducing operational complexity. This work positions DNET as an OS‑layer interface for value transfer, offering a structural standard for future financial infrastructure.

Ayotunde Oyatomi

The contemporary distributed systems are becoming highly dependent on strong security protocols to secure sensitive information, maintain continuity services, and sustain the trust of people in highly networked systems. With the increasingly advanced cyber threats, centralized security architectures are increasingly limited in ensuring confidentiality, integrity, and availability. This paper explores the idea of Distributed Ledger Technology (DLT) as a new security paradigm to improve trust and resiliency of distributed infrastructures. A systematic review of the literature has been done, with the establishment of a conceptual framework to serve as an assessment of how mechanisms of DLT can be applied to overcome the fundamental security issues. The review summarizes the recent empirical and theoretical research results to evaluate the efficiency of blockchain and ledger technologies associated with securing distributed systems. The findings show that classifications of immutability and cryptographic access controls in data integrity and decentralized consensus models enhance the availability and security of data, respectively. Nonetheless, trade-offs were discovered that were never previously anticipated, specifically, scalability and security. When more transaction throughput is achieved, decentralization tends to decrease, and the risk of vulnerabilities also increases. Also, energy usage and latency are significant issues for large-scale deployments. On the whole, this paper has concluded that even though DLT has significant security advantages, its implementation should be well-coordinated with system needs and operational limitations. The results provide useful advice to secure system designers who want to optimize performance, cost, and resilience of the next generation distributed environment (

Marc Leinweber

Resilience is the ability of a (distributed) system to withstand any stressful situation without imposing massive restrictions and, above all, without long-term consequences. Permissioned distributed ledgers based on state machine replication (SMR) offer a promising approach to achieving high resilience and fairness in federated systems. SMR provides a fault-tolerant service for clients by relying on all replicas being in a consistent state. The consistent state is achieved through a consensus algorithm, typically an atomic broadcast, that decides on a total order of client requests. In the Byzantine fault model, replicas are assumed to be potentially malicious; a Byzantine fault-tolerant (BFT) protocol withstands a fixed share of malicious actors. Classic BFT SMR protocols require $n>3t$ replicas and multiple rounds of communication to withstand $t$ faulty replicas, making the implementation complex and limiting achievable throughput and increasing latency. Trusted Execution Environments (TEEs) allow to implement SMR in the so-called hybrid fault model in which replicas are assumed to be potentially Byzantine but the TEE is restricted to only fail by crashing. In the hybrid fault model, SMR requires less communication and can be implemented with a fault tolerance of $n>2t$ replicas. While many proposals aim to optimize BFT SMR by using TEEs, they still rely on a so-called leader that coordinates the agreement process among the replicas. The leader is known to be a bottleneck and, if it fails, the system has to recover from the failure and elect a new leader. The additional coordination required to elect a new leader can cause significant performance degradation, limiting the achieved resilience. Asynchronous protocols based on directed acyclic graphs (DAGs) eliminate the reliance on distinguished replicas by allowing all replicas to participate equally in the agreement process. While asynchronous approaches and the hybrid fault model independently contribute to increasing the resilience of BFT SMR systems, their combination has largely been unexplored. This dissertation aims to fill this gap by answering the following research question: What is the achievable performance and resilience of DAG-based, hybrid fault-tolerant state machine replication and under which preconditions can the leaderless nature be safely exploited to maximize throughput? We proceed in three steps to enhance the resilience and performance of BFT SMR systems and to identify potential trade-offs that arise from the assumption of TEEs and asynchrony in BFT SMR. First, we investigate the fit of TEE-based SMR for consortium-operated applications using the example of Mobility-as-a-Service ticketing systems. We propose an SMR application that uses TEEs to protect sensitive customer and mobility provider data while limiting possibilities for fraud by both customers and mobility providers, and ensuring correct billing. We find that as long as secure multiparty computation is not competitive in terms of performance, TEE-based SMR can provide significant advantages in terms of efficiency and resilience while providing reasonable confidentiality guarantees. We describe the characteristics of the Mobility-as-a-Service use case and identify similar use cases from other domains, e.g., central bank digital currencies, allowing us to conclude that our findings generalize. In the second step, we establish the foundation for a comprehensive analysis by proposing and proving TEE-Rider, the first hybrid fault-tolerant, asynchronous, and DAG-based atomic broadcast protocol. TEE-Rider builds upon the DAG-Rider protocol family and an optimized, DAG-aware, and TEE-based causal order broadcast we propose and prove. We then identify fundamental issues that arise from the combination of TEEs and asynchrony in BFT SMR. These are the impossibility of a fault-tolerant setup and the impossibility of garbage collection. Furthermore, we prove that for partially synchronous, TEE-based reliable broadcast it is impossible to reinitialize a TEE after a crash without relying on the participation of all $n$ replicas. We conclude the theoretical contributions with the proposal of the NxBFT SMR framework. Following an assumption-algorithm co-design, NxBFT is built upon TEE-Rider for the "Not eXactly Byzantine" (NxB) operating model to maximize throughput without sacrificing resilience. Moreover, NxBFT leverages SMR state transfer to circumvent the limitations imposed by TEEs and asynchrony and provides, under the assumption of partial synchrony, garbage collection, recovery, and reconfiguration. Finally, we contribute an extensive empirical evaluation. To this end, we develop the ABCperf evaluation framework focusing on the fair and straightforward comparison of fault-tolerant SMR and agreement protocols. We investigate the performance characteristics of NxBFT and find that cryptographic operations for signature creation and verification are the main bottleneck. We compare the performance of NxBFT with the state-of-the-art leader-based, hybrid fault-tolerant protocols MinBFT and Chained-Damysus and investigate the impact of the SMR client model (BFT vs. NxB), payload sizes, network sizes, network latencies, and crash faults. While all algorithms can benefit from the NxB client model, NxBFT achieves the highest throughput in all scenarios with up to $\sim500\,000$ requests per second. All algorithms show an improvement of the end-to-end latency when using the BFT instead of the NxB client model. When small latencies are required, MinBFT and Damysus are at an advantage with Damysus showing competitive throughput and impressively low latencies for small deployments. In contrast to leader-based approaches, NxBFT's performance is almost not impacted when actual crash faults occur.

Steven Paul Nohr

Transaction fees are a core economic mechanism in blockchain systems, intended to price scarce blockspace and align resource consumption with economic cost. However, in Proof-of-Stake (PoS) and decentralized finance (DeFi) environments, fee mechanisms can be exploited to impose asymmetric and persistent economic harm without violating protocol rules. This paper defines <b><i>Gas Fee Drain Loops</i></b>, commonly referred to as <i>grief attacks</i>, as a class of economic exhaustion attacks that weaponize execution costs, transaction ordering, and revert semantics to drain capital from targeted participants. We analyze the structural conditions that enable such attacks, demonstrate why conventional fee market assumptions fail under adversarial strategies, and show how gas griefing degrades security through economic exclusion rather than consensus failure. Finally, we propose a logic-layer mitigation model that bounds execution costs, restores economic symmetry, and preserves open participation under adversarial conditions.

Steven Paul Nohr

<b><i>Proof-of-Stake (PoS)</i></b> blockchain networks replace energy-intensive mining with validator-based block production and transaction ordering. While this design improves efficiency and scalability, it introduces a largely unexamined structural vulnerability: deterministic or predictable validator sequencing. This paper defines <b>Sequential Validator Front-Running</b><b> </b>as a validator-level exploit whereby participants leverage foreknowledge of execution slots to extract economic advantage, manipulate outcomes, or preempt competing transactions. Unlike classical Miner/Maximal Extractable Value (MEV), this exploit arises from consensus scheduling itself rather than transaction visibility alone. We analyze the structural causes of this vulnerability, demonstrate why conventional mitigations such as governance controls, slashing, and post-hoc monitoring are insufficient, and propose a logic-layer sequencing constraint framework enforced at block construction time. The proposed approach neutralizes sequencing abuse while preserving throughput, finality, and protocol compliance.

Arda Hacıfevzioğlu, Kübra Kalkan

No abstract is available for this record.

Swaminathan Balasubramaniam, Jorge Sabat, Luana Zaccaria

Proof-of-stake networks implement incentive-compatible transaction verification by requiring validators to post collateral, or stake, that can be forfeited upon failure. While the resilience of these networks rests on decentralization, validation activity is increasingly delegated to few professional operators. Motivated by the September 2025 Kiln security incident, where professional-but not solo-validators experienced a sharp decline in effectiveness, we develop a model of delegated validation. Delegation expands access by pooling collateral and lowering the operational burden borne by individual validators, and can improve efficiency through professional expertise and scale. At the same time, delegated validation concentrates operational infrastructure, increasing exposure to common shocks. The protocol therefore faces a tradeoff: tighter collateral requirements strengthen discipline, but can shift activity toward intermediated providers, raising concentration and correlated losses in stress states. Liquid staking tokens amplify this tradeoff by adding private liquidity and collateral-use benefits to delegation, and can move the system from a low-delegation equilibrium to a self-sustaining high-delegation equilibrium. Anti-correlation penalties mitigate this force by pricing correlated failures more directly and can reduce reliance on high collateral requirements.

Mohammad Pishdar, Jawad Manzoor

ABSTRACT Blockchain technology has emerged as a foundational infrastructure for decentralized applications, where consensus protocols play a critical role in ensuring security, consistency and trust among distributed participants. This paper presents a comprehensive comparative analysis of nine widely adopted consensus protocols across public (proof of work [PoW], proof of stake [PoS], delegated proof of stake [DPoS]) and private (practical Byzantine fault tolerance [PBFT, Raft, Kafka, proof of elapsed time [PoET], yet another consensus [YAC], Paxos) blockchain systems. Unlike prior surveys, this work integrates workflow‐level operational modelling, quantitative performance comparison and application‐driven decision support within a unified analytical framework. Our analysis shows that PoW achieves strong decentralization at 3–15 transactions per second (TPS) with 10–60 min finality, whereas PoS improves throughput to tens to thousands of TPS with seconds‐to‐minutes finality while reducing energy consumption by approximately 99%. Private blockchain protocols such as PBFT and Kafka achieve sub‐second latency and throughput exceeding 10,000 TPS by trading off decentralization for performance and control. Furthermore, we develop a decision‐support framework that maps consensus mechanisms to application requirements and provides a critical synthesis of security risks, scalability limitations, and emerging solutions. The findings highlight that no single protocol satisfies all design goals, reinforcing the necessity of context‐aware consensus selection.

Alsaadah Saif Mohammed ALabri, Shahd Ibrahim Ali AL Balushi

Blockchain is a distributed database used to store an unchangeable, permanent record of all transactions. It is operated by processors that are a member of a peer-to-peer (P2P) network and functions as a decentralized database. Demand for decentralized applications (DApps), which provide accountability, safety, and independence beyond conventional centralized systems, is rising as a result of the quick development of blockchain technology. However, combining frontend, back end, and blockchain components into a unified and effective framework might be difficult for DApp designers. In order to simplify the creation of decentralized applications, this study suggests a full-stack blockchain framework that connects various levels. The framework creates an end-to-end development environment designed for compatibility and scalability by utilizing contemporary technologies, such as Solidity, with Web3.js for smart contract integration, React.js for the front-end, and Node.js/Express.js for the backend. Using cryptographic methods and decentralized storage (like IPFS), a layered architecture is intended to provide modularity, effective data flow, and increased security. The suggested framework streamlines DApp development processes, lowers latency in blockchain interactions, and boosts developer efficiency, according to implementation data. By offering a thorough architectural blueprint and execution method for full-stack DApp creation, this study advances the area of blockchain engineering and opens the door for safe, effective, and user-focused decentralized ecosystems.

Павло Жержерунов, Oleksandr Shmatko

Dockerised blockchain solution can mitigate the low levels of distributed technology adoption in small and medium enterprises. It can be done via designing and implementing an environment which inherits ease of deployment and scalability of containerized systems with safety and transparency of distributed applications. Practical implementation of a dockerized blockchain solution designed as a demonstrative implementation for existing client–server architecture is described in this paper. This solution uses Docker containers to simplify the setup and deployment of a private blockchain network, a mediator server and a reverse proxy. Implementation of this system on a low scale demonstrates feasibility of integrating blockchain technology into existing business processes without fundamental architectural changes and acknowledges deployment and maintaining challenges that usually accompany distributed systems using private blockchain. Discussed implementation is a demonstration of designed architecture being potentially a reproducible and easily maintainable environment for logging and validating data through an immutable ledger on a smaller scale. Proof of concept successfully validates the core idea. The implementation shows a mediator server intercepting client request, recording them on a private Ethereum blockchain via a JSON-RPC interface, and then forwarding them to the original server. This confirms the solution’s ability to introduce a trusted, intermediate layer for data immutability. The project demonstrates a working framework for embedding distributed ledger technologies into client–server ecosystems. While the current Proof of Work consensus mechanism presents scalability limitations, the architecture provides a strong foundation for future research, including migrating to more efficient consensus mechanisms and integrating smart contracts.

Pavlo Zherzherunov, Olexandr Shmatko

Dockerised blockchain solution can mitigate the low levels of distributed technology adoption in small and medium enterprises. It can be done via designing and implementing an environment which inherits ease of deployment and scalability of containerized systems with safety and transparency of distributed applications. Practical implementation of a dockerized blockchain solution designed as a demonstrative implementation for existing client–server architecture is described in this paper. This solution uses Docker containers to simplify the setup and deployment of a private blockchain network, a mediator server and a reverse proxy. Implementation of this system on a low scale demonstrates feasibility of integrating blockchain technology into existing business processes without fundamental architectural changes and acknowledges deployment and maintaining challenges that usually accompany distributed systems using private blockchain. Discussed implementation is a demonstration of designed architecture being potentially a reproducible and easily maintainable environment for logging and validating data through an immutable ledger on a smaller scale. Proof of concept successfully validates the core idea. The implementation shows a mediator server intercepting client request, recording them on a private Ethereum blockchain via a JSON-RPC interface, and then forwarding them to the original server. This confirms the solution’s ability to introduce a trusted, intermediate layer for data immutability. The project demonstrates a working framework for embedding distributed ledger technologies into client–server ecosystems. While the current Proof of Work consensus mechanism presents scalability limitations, the architecture provides a strong foundation for future research, including migrating to more efficient consensus mechanisms and integrating smart contracts.

Marko Vukolić, Orestis Alpos, Jakov Mitrovski, Themis Papameletiou · 6 authors

This paper introduces Bitcoin-IPC, a protocol that scales Bitcoin through a network of permissionless, interconnected, programmable Proof-of-Stake (PoS) Layer-2 chains, called subnets, whose stake is denominated in L1 BTC. These subnets rely on Bitcoin L1 for the communication of critical information, settlement, and security. Subnets can communicate with each other and with Bitcoin: users deposit BTC from Bitcoin to a subnet and withdraw it back, and transfer wBTC directly between subnets. We provide formal definitions of these bridge protocols, incorporating a firewall property that limits the impact of malicious subnets on the security of the broader network. Our design, inspired by SWIFT messaging and embedded within Bitcoin's SegWit mechanism, enables seamless value transfer across L2 subnets. Uniquely, this mechanism reduces the virtual-byte cost per transaction (vB/tx) by up to 23x, compared to transacting natively on Bitcoin L1, effectively increasing monetary-transaction throughput from 7 tps to over 160 tps, without requiring any modifications to Bitcoin L1.

Kichang Lee, Sungmin Lee, Jaeho Jin, JeongGil Ko

Modern cloud-based AI training relies on extensive telemetry and logs to ensure accountability. While these audit trails enable retrospective inspection, they struggle to address the inherent non-determinism of deep learning. Stochastic operations, such as dropout, create an ambiguity surface where attackers can mask malicious manipulations as natural random variance, granting them plausible deniability. Consequently, existing logging mechanisms cannot verify whether stochastic values were generated and applied honestly without exposing sensitive training data. To close this integrity gap, we introduce Verifiable Dropout, a privacy-preserving mechanism based on zero-knowledge proofs. We treat stochasticity not as an excuse but as a verifiable claim. Our approach binds dropout masks to a deterministic, cryptographically verifiable seed and proves the correct execution of the dropout operation. This design enables users to audit the integrity of stochastic training steps post-hoc, ensuring that randomness was neither biased nor cherry-picked, while strictly preserving the confidentiality of the model and data.

Tarik Ouardi

Temporal-Angular Quantum Addressing (TAQA) specifies a practical coordination layer for distributed quantum systems that operationalizes cycle-anchored phase-window execution. TAQA is designed for architectures where long-horizon absolute timestamp synchronization cannot be guaranteed and where continuous external timing infrastructure (GNSS, dedicated timing links, etc.) is undesirable, unavailable, or untrusted. Core idea Instead of scheduling actions at an absolute time, TAQA schedules actions by phase conditions on a shared cyclic phase convention \( \phi(t)\in[0,1)\cong \mathbb{S}^1 \) together with an explicit cycle index. Nodes execute when their locally estimated phase enters an agreed wrap-around-safe acceptance window within the intended cycle. This avoids “same phase / wrong cycle” ambiguity and supports deterministic coordination under explicit short-horizon error assumptions. What TAQA defines TAQA defines how to express and execute distributed quantum-network actions using classical metadata: Execution primitive (Q-Address style): TAQA expresses each executable action as a macro window + micro slot instruction. The macro window encodes the intended cycle and phase acceptance window; the micro slot provides local sequencing/offset ordering within that window using local hardware timing. Tick-canonical semantics: For interoperability and verification, TAQA adopts fixed-point ticks (integers) as canonical semantics (no floating-point boundary checks). Human-facing displays (HS degrees, HS index, SWT labels, etc.) are derived-only and must not be used for verification or boundary gating. Cycle anchoring: Every executable instruction is explicitly anchored to an intended cycle index to prevent ambiguous interpretation across repeated cycles. Optional audit hook: TAQA supports an optional post-execution signed audit receipt (TSAE-style) using the same tick-canonical context fields, suitable for optional anchoring (e.g., a ledger/Clockchain pattern). What TAQA does NOT define TAQA is a control-plane / metadata layer and does not modify quantum mechanics: It does not introduce a quantum time operator and does not change the Hilbert space. It does not define bootstrapping or clock-parameter estimation algorithms (offset/drift). These are handled by external initialization/tracking layers (e.g., bootstrapping protocols). It does not define cryptographic primitives or threat models. Security is defined by external, versioned security profiles. Applications enabled by TAQA TAQA provides a deterministic coordination layer for common distributed-quantum workflows, including: Phase-aligned distributed gate execution: remote node actions are triggered in the same cycle-anchored window; micro timing is local. Entanglement distribution scheduling: photon emission windows and BSM windows can be scheduled to coincide without continuous absolute-time synchronization. Temporal routing labels: cycle-anchored contexts can be used as temporal labels for routing, prioritization, and scheduling in repeater networks and distributed workflows. Security model (plug-in interface) TAQA treats Timeverse/Q-Address/TSAE fields as public context (not secrets). Security (signatures, nonce policy, anti-replay rules, canonical encoding, algorithm suites) is provided by an external Security Profile selected via a suite identifier (e.g., security_profile_id). TAQA fields may be bound as associated data (domain separation), but confidentiality and integrity are provided by the security layer. Normative dependencies (DOIs) TAQA is interoperable by construction and relies on the following published normative specifications: Phase-Coordination Series Conventions:https://doi.org/10.5281/zenodo.18068999 Q-Address: Macro Phase + Micro Slot:https://doi.org/10.5281/zenodo.18068997 Timeverse Security Profile:https://doi.org/10.5281/zenodo.18069423 Related context Theorem of Temporal Resolution Limitation and the Phase-Coordination Principle (v1.1):https://doi.org/10.5281/zenodo.17955430 Quantum Bootstrapping Protocol (QBP) v1.2:https://doi.org/10.5281/zenodo.18064435 Keywords: TAQA, distributed quantum computing, quantum networks, phase coordination, phase windows, cycle anchoring, Q-Address, ticks, interoperability, control plane, audit receipts, security profiles.

Sinka Gao, Guoqiang Li

Abstract In the realm of blockchains, synchronization challenges are two-folded. First, smart contracts from different blockchains cannot communicate with each other, making it hard to establish a trustworthy communication channel to share and maintain a universal state between each other. Second, transactions on different blockchains can hardly be ordered. Hence interference is expected. We need a novel way to handle interference. Traditional solutions involving third parties have safety and liveness issues and thus compromise between safety, permissionless, and liveness. ZK Multi-Blockchain Aggregatoris a multi-blockchain execution layer that leverages the power of zero-knowledge proof to minimize the trust base of multi-blockchain communication, which does not compromise safety, liveness, permissionless, and atomicity. In contrast to traditional blockchain bridges performing transactions on different blockchains separately and using a relay system to enforce the order of transactions and prevent interference, our method uses an entirely new approach, such that for each multi-blockchain transaction, it simulates the multi-blockchain transaction in its aggregator chain. Our aggregator uses zero-knowledge proofs of the simulation to convince involved blockchains to update their local state accordingly. On top of this layer, rich applications over multi-blockchains can run safely and efficiently.

Xi Lin, Junfeng Tian

Blockchain consensus mechanisms are fundamental to the security and decentralization of distributed ledgers. In Proof-of-Stake (PoS) systems, which are lauded for their energy efficiency, the fair and unpredictable selection of block proposers is paramount and relies heavily on secure random number generation. The RANDAO random number generation mechanism in the Gasper protocol is susceptible to hash collision attack, which can introduce adversarial bias in the block proposer selection process. From the perspective of resisting adversarial bias attacks, this paper examines the optimization of the Gasper consensus protocol, focusing on security issues such as vulnerabilities to hash collisions in RANDAO and high latency in asynchronous network environments. By analyzing the spatial–temporal distribution of historical block hashes, we propose a dual-round random number verification mechanism that enhances reliability through multiple validation models. We develop a dynamic game-theoretic model under incomplete information to analyze node strategy selection and interaction dynamics. Our experimental results demonstrate that the improved protocol (RABA-Gasper) offers superior resistance to attacks, fairness, and efficiency compared to conventional protocols. RABA-Gasper outperforms conventional ones, achieving a 6.8% attack success rate (vs. 32.7% for RANDAO and 18.2% for Two Look-Back) with 94.3% hash collision detection, a proposer Gini coefficient below 0.23, 2.3x higher throughput retention than RANDAO in asynchronous networks, and a slightly increased random number generation latency of 125 ms. Supported by a game-theoretic model, it guarantees security when honest nodes account for ≥2/3 of the total.

Ali Farahbakhsh, Giuliano Losa, Youer Pu, Lorenzo Alvisi · 5 authors

Permissionless blockchains achieve consensus while allowing unknown nodes to join and leave the system at any time. They typically come in two flavors: proof of work (PoW) and proof of stake (PoS), and both are vulnerable to attacks. PoS protocols suffer from long-range attacks, wherein attackers alter execution history at little cost, and PoW protocols are vulnerable to attackers with enough computational power to subvert execution history. PoS protocols respond by relying on external mechanisms like social consensus; PoW protocols either fall back to probabilistic guarantees, or are slow. We present Sieve-MMR, the first fully-permissionless protocol with deterministic security and constant expected latency that does not rely on external mechanisms. We obtain Sieve-MMR by porting a PoS protocol (MMR) to the PoW setting. From MMR we inherit constant expected latency and deterministic security, and proof-of-work gives us resilience against long-range attacks. The main challenge to porting MMR to the PoW setting is what we call time-travel attacks, where attackers use PoWs generated in the distant past to increase their perceived PoW power in the present. We respond by proposing Sieve, a novel algorithm that implements a new broadcast primitive we dub time-travel-resilient broadcast (TTRB). Sieve relies on a black-box, deterministic PoW primitive to implement TTRB, which we use as the messaging layer for MMR.

Jiayong Chai, Jun Guo, Muhua Wei, Mo Chen · 5 authors

Blockchain systems have been widely adopted in today’s society, with consensus algorithms serving as their core component to ensure all participants in the network agree on a specific data state. Existing consensus algorithms such as Proof of Work (PoW), Proof of Stake (PoS), and the Practical Byzantine Fault-Tolerant Algorithm (PBFT) exhibit certain limitations in terms of scalability, security, and efficiency. To address these limitations, this paper proposes a novel Network-based Reputation Consensus (NRC) algorithm. The main research contributions of this work include the following: (1) An intelligent grouping mechanism that dynamically groups nodes based on network awareness, forming consensus groups with low internal latency and high bandwidth utilization, significantly reducing intra-group communication overhead. (2) A dynamic reputation system incorporating a “diminishing returns” reward function and a “multiplicative penalty” mechanism, effectively incentivizing honest node participation while preventing power monopoly. (3) A two-phase model of “intra-group BFT consensus + global communication committee ordering” that decomposes complex global consensus into parallel intra-group processing and coordination among a small set of elite nodes, thereby drastically improving efficiency. (4) Comprehensive simulations comparing the NRC algorithm with mainstream consensus algorithms, demonstrating its superior performance in communication overhead, throughput, latency, and tolerance to malicious nodes, thereby laying the foundation for large-scale applications.

Ayush Nainwal, Atharva Kamble, Nitin Awathare

Zero-knowledge proofs (ZKPs) are central to secure and privacy-preserving computation, with zk-SNARKs and zk-STARKs emerging as leading frameworks offering distinct trade-offs in efficiency, scalability, and trust assumptions. While their theoretical foundations are well studied, practical performance under real-world conditions remains less understood. In this work, we present a systematic, implementation-level comparison of zk-SNARKs (Groth16) and zk-STARKs using publicly available reference implementations on a consumer-grade ARM platform. Our empirical evaluation covers proof generation time, verification latency, proof size, and CPU profiling. Results show that zk-SNARKs generate proofs 68x faster with 123x smaller proof size, but verify slower and require trusted setup, whereas zk-STARKs, despite larger proofs and slower generation, verify faster and remain transparent and post-quantum secure. Profiling further identifies distinct computational bottlenecks across the two systems, underscoring how execution models and implementation details significantly affect real-world performance. These findings provide actionable insights for developers, protocol designers, and researchers in selecting and optimizing proof systems for applications such as privacy-preserving transactions, verifiable computation, and scalable rollups.