The ultra-high speed,ultra-low latency,and massive connectivity of the 6 th Generation Mobile Network(6G)present unprecedented challenges to network security.In addition,the deep integration of Artificial Intelligence...The ultra-high speed,ultra-low latency,and massive connectivity of the 6 th Generation Mobile Network(6G)present unprecedented challenges to network security.In addition,the deep integration of Artificial Intelligence(AI)into 6G networks introduces AI-native features that further complicate the design and implementation of secure network architectures.To meet the security demands posed by the massive number of devices and edge nodes in 6G networks,a decentralized security architecture is essential,as it effectively mitigates the performance bottlenecks typically associated with centralized systems.Blockchain technology offers a promising trust mechanism among devices in 6G networks.However,conventional blockchain systems suffer from limited scalability under high-load conditions,making them inadequate for supporting a large volume of nodes and frequent data exchanges.To overcome these limitations,We propose Shard-DAG,a scalable architecture that structurally integrates Directed Acyclic Graphs(DAG)and sharding.Each shard adopts a Block-DAG structure for parallel block processing,effectively overcoming the performance bottlenecks of traditional chain-based blockchains.Furthermore,we introduce a DAG-based transaction ordering mechanism within each shard to defend against double-spending attacks.To ensure inter-shard security,Block-DAG adopts a black-box interaction approach to prevent cross-shard double-spending.Theoretical analysis and experimental evaluations demonstrate that Shard-DAG achieves near-linear scalability.In a network of 1,200 nodes with 8 shards,Shard-DAG achieves peak throughput improvements of 14.64 times over traditional blockchains,8.61 times over standalone BlockDAG,and 2.05 times over conventional sharded blockchains.The results validate Shard-DAG's ability to scale efficiently while maintaining robust security properties.展开更多
Managing sensitive data in dynamic and high-stakes environments,such as healthcare,requires access control frameworks that offer real-time adaptability,scalability,and regulatory compliance.BIG-ABAC introduces a trans...Managing sensitive data in dynamic and high-stakes environments,such as healthcare,requires access control frameworks that offer real-time adaptability,scalability,and regulatory compliance.BIG-ABAC introduces a transformative approach to Attribute-Based Access Control(ABAC)by integrating real-time policy evaluation and contextual adaptation.Unlike traditional ABAC systems that rely on static policies,BIG-ABAC dynamically updates policies in response to evolving rules and real-time contextual attributes,ensuring precise and efficient access control.Leveraging decision trees evaluated in real-time,BIG-ABAC overcomes the limitations of conventional access control models,enabling seamless adaptation to complex,high-demand scenarios.The framework adheres to the NIST ABAC standard while incorporating modern distributed streaming technologies to enhance scalability and traceability.Its flexible policy enforcement mechanisms facilitate the implementation of regulatory requirements such as HIPAA and GDPR,allowing organizations to align access control policies with compliance needs dynamically.Performance evaluations demonstrate that BIG-ABAC processes 95% of access requests within 50 ms and updates policies dynamically with a latency of 30 ms,significantly outperforming traditional ABAC models.These results establish BIG-ABAC as a benchmark for adaptive,scalable,and context-aware access control,making it an ideal solution for dynamic,high-risk domains such as healthcare,smart cities,and Industrial IoT(IIoT).展开更多
The Internet of Things(IoT)ecosystem faces growing security challenges because it is projected to have 76.88 billion devices by 2025 and $1.4 trillion market value by 2027,operating in distributed networks with resour...The Internet of Things(IoT)ecosystem faces growing security challenges because it is projected to have 76.88 billion devices by 2025 and $1.4 trillion market value by 2027,operating in distributed networks with resource limitations and diverse system architectures.The current conventional intrusion detection systems(IDS)face scalability problems and trust-related issues,but blockchain-based solutions face limitations because of their low transaction throughput(Bitcoin:7 TPS(Transactions Per Second),Ethereum:15-30 TPS)and high latency.The research introduces MBID(Multi-Tier Blockchain Intrusion Detection)as a groundbreaking Multi-Tier Blockchain Intrusion Detection System with AI-Enhanced Detection,which solves the problems in huge IoT networks.The MBID system uses a four-tier architecture that includes device,edge,fog,and cloud layers with blockchain implementations and Physics-Informed Neural Networks(PINNs)for edge-based anomaly detection and a dual consensus mechanism that uses Honesty-based Distributed Proof-of-Authority(HDPoA)and Delegated Proof of Stake(DPoS).The system achieves scalability and efficiency through the combination of dynamic sharding and Interplanetary File System(IPFS)integration.Experimental evaluations demonstrate exceptional performance,achieving a detection accuracy of 99.84%,an ultra-low false positive rate of 0.01% with a False Negative Rate of 0.15%,and a near-instantaneous edge detection latency of 0.40 ms.The system demonstrated an aggregate throughput of 214.57 TPS in a 3-shard configuration,providing a clear,evidence-based path for horizontally scaling to support overmillions of devices with exceeding throughput.The proposed architecture represents a significant advancement in blockchain-based security for IoT networks,effectively balancing the trade-offs between scalability,security,and decentralization.展开更多
Confronting the escalating global challenge of counterfeit products,developing advanced anticounterfeiting materials and structures with physical unclonable functions(PUFs)has become imperative.All-optical PUFs,distin...Confronting the escalating global challenge of counterfeit products,developing advanced anticounterfeiting materials and structures with physical unclonable functions(PUFs)has become imperative.All-optical PUFs,distinguished by their high output complexity and expansive response space,offer a promising alternative to conventional electronic counterparts.For practical authentications,the expansion of optical PUF keys usually involves intricate spatial or spectral shaping of excitation light using bulky external apparatus,which largely hinders the applications of optical PUFs.Here,we report a plasmonic PUF system based on heterogeneous nanostructures.The template-assisted shadow deposition technique was employed to adjust the morphological diversity of densely packed metal nanoparticles in individual PUFs.Transmission images were processed via a hash algorithm,and the generated PUF keys with a scalable capacity from 2875 to 243401 exhibit excellent uniqueness,randomness,and reproducibility.Furthermore,the wavelength and the polarization state of the excitation light are harnessed as two distinct expanding strategies,offering the potential for multiscenario applications via a single PUF.Overall,our reported plasmonic PUFs operated with the multidimensional expanding strategy are envisaged to serve as easy-to-integrate,easy-to-use systems and promise efficacy across a broad spectrum of applications,from anticounterfeiting to data encryption and authentication.展开更多
The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneousl...The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneously continues to elude most blockchain systems,often forcing trade-offs that limit their real-world applicability.This review paper synthesizes current research efforts aimed at resolving the trilemma,focusing on innovative consensus mechanisms,sharding techniques,layer-2 protocols,and hybrid architectural models.We critically analyze recent breakthroughs,including Directed Acyclic Graph(DAG)-based structures,cross-chain interoperability frameworks,and zero-knowledge proof(ZKP)enhancements,which aimto reconcile scalability with robust security and decentralization.Furthermore,we evaluate the trade-offs inherent in these approaches,highlighting their practical implications for enterprise adoption,decentralized finance(DeFi),and Web3 ecosystems.By mapping the evolving landscape of solutions,this review identifies gaps in currentmethodologies and proposes future research directions,such as adaptive consensus algorithms and artificial intelligence-driven(AI-driven)governance models.Our analysis underscores that while no universal solution exists,interdisciplinary innovations are progressively narrowing the trilemma’s constraints,paving the way for next-generation blockchain infrastructures.展开更多
The integration of the dynamic adaptive routing(DAR)algorithm in unmanned aerial vehicle(UAV)networks offers a significant advancement in addressing the challenges posed by next-generation communication systems like 6...The integration of the dynamic adaptive routing(DAR)algorithm in unmanned aerial vehicle(UAV)networks offers a significant advancement in addressing the challenges posed by next-generation communication systems like 6G.DAR’s innovative framework incorporates real-time path adjustments,energy-aware routing,and predictive models,optimizing reliability,latency,and energy efficiency in UAV operations.This study demonstrated DAR’s superior performance in dynamic,large-scale environments,proving its adaptability and scalability for real-time applications.As 6G networks evolve,challenges such as bandwidth demands,global spectrum management,security vulnerabilities,and financial feasibility become prominent.DAR aligns with these demands by offering robust solutions that enhance data transmission while ensuring network reliability.However,obstacles like global route optimization and signal interference in urban areas necessitate further refinement.Future directions should explore hybrid approaches,the integration of machine learning,and comprehensive real-world testing to maximize DAR’s capabilities.The findings underscore DAR’s pivotal role in enabling efficient and sustainable UAV communication systems,contributing to the broader landscape of wireless technology and laying a foundation for the seamless transition to 6G networks.展开更多
A new scheme combining a scalable transcoder with space time block codes (STBC) for an orthogonal frequency division multiplexing (OFDM) system is proposed for robust video transmission in dispersive fading channe...A new scheme combining a scalable transcoder with space time block codes (STBC) for an orthogonal frequency division multiplexing (OFDM) system is proposed for robust video transmission in dispersive fading channels. The target application for such a scalable transcoder is to provide successful access to the pre-encoded high quality video MPEG-2 from mobile wireless terminals. In the scalable transcoder, besides outputting the MPEG-4 fine granular scalability (FGS) bitstream, both the size of video frames and the bit rate are reduced. And an array processing algorithm of layer interference suppression is used at the receiver which makes the system structure provide different levels of protection to different layers. Furthermore, by considering the important level of scalable bitstream, the different bitstreams can be given different level protection by the system structure and channel coding. With the proposed system, the concurrent large diversity gain characteristic of STBC and alleviation of the frequency-selective fading effect of OFDM can be achieved. The simulation results show that the proposed schemes integrating scalable transcoding can provide a basic quality of video transmission and outperform the conventional single layer transcoding transmitted under the random and bursty error channel conditions.展开更多
Topology aggregation is necessary for scalable QoS routing mechanisms. Thekey issue is how to gain good performance while summarizing the topological information. In thispaper, we propose a new method to describe the ...Topology aggregation is necessary for scalable QoS routing mechanisms. Thekey issue is how to gain good performance while summarizing the topological information. In thispaper, we propose a new method to describe the logical link, which is simple and effective innetwork with additive and constrained concave parameters. We extend the method to network associatedwith multi-parameters. Furthermore, we propose a modified star aggregation algorithm. Simulationsare used to evaluate the performance. The results show that our algorithm is relatively good.展开更多
针对区域防空反导作战中各要素复杂耦合所导致的战场态势快速演变、来袭目标数量动态变化等难题,提出一种基于可动态扩展且带时空推理的QMIX(QMIX with Dynamic extension and Spatiotemporal reasoning, QMIX-DS)的火力分配方法,以火...针对区域防空反导作战中各要素复杂耦合所导致的战场态势快速演变、来袭目标数量动态变化等难题,提出一种基于可动态扩展且带时空推理的QMIX(QMIX with Dynamic extension and Spatiotemporal reasoning, QMIX-DS)的火力分配方法,以火力单元作为智能体构建决策网络,生成火力分配策略。核心改进为:为每个智能体的决策网络设计可动态扩展特征编码模块,自适应处理数量变化的来袭目标,并引入对比学习突出目标类别属性,形成差异化特征表征;构建两层多头自注意力机制捕捉不同类别目标间的动态时空依赖关系,快速推理任务过程中的态势演变,优化火力分配策略。基于墨子平台不同规模的仿真结果表明,所提出的火力分配方法能够在动态变化的战场条件下生成有效的防空反导策略,与基线算法及其他主流算法相比,所提QMIX-DS算法在目标拦截率、阵地存活率、导弹消耗数量等指标上均体现出了优势,并在不同场景中展现出较高的扩展性和泛化性。展开更多
Lightweight nodes are crucial for blockchain scalability,but verifying the availability of complete block data puts significant strain on bandwidth and latency.Existing data availability sampling(DAS)schemes either re...Lightweight nodes are crucial for blockchain scalability,but verifying the availability of complete block data puts significant strain on bandwidth and latency.Existing data availability sampling(DAS)schemes either require trusted setups or suffer from high communication overhead and low verification efficiency.This paper presents ISTIRDA,a DAS scheme that lets light clients certify availability by sampling small random codeword symbols.Built on ISTIR,an improved Reed–Solomon interactive oracle proof of proximity,ISTIRDA combines adaptive folding with dynamic code rate adjustment to preserve soundness while lowering communication.This paper formalizes opening consistency and prove security with bounded error in the random oracle model,giving polylogarithmic verifier queries and no trusted setup.In a prototype compared with FRIDA under equal soundness,ISTIRDA reduces communication by 40.65%to 80%.For data larger than 16 MB,ISTIRDA verifies faster and the advantage widens;at 128 MB,proofs are about 60%smaller and verification time is roughly 25%shorter,while prover overhead remains modest.In peer-to-peer emulation under injected latency and loss,ISTIRDA reaches confidence more quickly and is less sensitive to packet loss and load.These results indicate that ISTIRDA is a scalable and provably secure DAS scheme suitable for high-throughput,large-block public blockchains,substantially easing bandwidth and latency pressure on lightweight nodes.展开更多
Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom a...Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom arrays,scalability is primarily constrained by the capacity to generate large numbers of optical tweezers,and conventional techniques using acousto-optic deflectors or spatial light modulators struggle to produce arrays much beyond∼10,000 tweezers.Moreover,these methods require additional microscope objectives to focus the light into micrometer-sized spots,which further complicates system integration and scalability.Here,we demonstrate the experimental generation of an optical tweezer array containing 280×280 spots using a metasurface,nearly an order of magnitude more than most existing systems.The metasurface leverages a large number of subwavelength phase-control pixels to engineer the wavefront of the incident light,enabling both large-scale tweezer generation and direct focusing into micron-scale spots without the need for a microscope.This result shifts the scalability bottleneck for atom arrays from the tweezer generation hardware to the available laser power.Furthermore,the array shows excellent intensity uniformity exceeding 90%,making it suitable for homogeneous single-atom loading and paving the way for trapping arrays of more than 10,000 atoms in the near future.展开更多
This paper presents a novel full-chip scalable routing framework that simultaneously considers the routing congestion and the circuit performance. In order to bridge the gap, the presented framework calls the detailed...This paper presents a novel full-chip scalable routing framework that simultaneously considers the routing congestion and the circuit performance. In order to bridge the gap, the presented framework calls the detailed router immediately after a global route is extracted. With the interleaving mode of global routing immediately followed by detailed routing, accurate routing resource and congestion information can be obtained, which provides valuable guidance for the following global routing process. The framework features the fast pattern and framed shortest path global router,a maze-based congestion-driven detailed router, and better interaction between the two routers. In the framework, timing critical nets can be assigned higher priority for performance concern, and different net ordering techniques can be adopted for different routing objectives. The framework is tested on a set of commonly used benchmark circuits and compared with a previous multilevel routing framework. Experimental results show that the presented framework obtains significantly better routing solutions than the previous one considering circuit performance, routing completion rate, and runtime.展开更多
The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design ...The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC. Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL) and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, in- cluding the design criteria, use cases, signaling and payload structure.展开更多
Dynamic Controller Provisioning Problem(DCPP) is a key problem for scalable SDN. Previously, the solution to this problem focused on adapting the number of controllers and their locations with changing network conditi...Dynamic Controller Provisioning Problem(DCPP) is a key problem for scalable SDN. Previously, the solution to this problem focused on adapting the number of controllers and their locations with changing network conditions, but ignored balancing control loads via switch migration. In this paper, we study a scalable control mechanism to decide which switch and where it should be migrated for more balanced control plane, and we define it as Switch Migration Problem(SMP). The main contributions of this paper are as follows. First, we define a SDN model to describe the relation between controllers and switches from the view of loads. Based on this model, we form SMP as a Network Utility Maximization(NUM) problem with the objective of serving more requests under available control resources. Second, we design a synthesizing distributed algorithm for SMP--- Distributed Hopping Algorithm(DHA), by approximating our optimal objective via Log-Sum-Exp function. In DHA, individual controller performs algorithmic procedure independently. With the solution space F, we prove that the optimal gap caused by approximation is at most 1/βlog|F|, and DHA procedure is equal to implementation of a time-reversible Markov Chain process. Finally, the results are corroborated by several numerical simulations.展开更多
Network Functions Virtualization(NFV) is an attempt to help operators more effectively manage their networks by implementing traditional network functions embedded in specialized hardware platforms in term of virtuali...Network Functions Virtualization(NFV) is an attempt to help operators more effectively manage their networks by implementing traditional network functions embedded in specialized hardware platforms in term of virtualized software instances. But, existing novel network appliances designed for NFV infrastructure are always architected on a general-purpose x86 server, which makes the performance of network functions limited by the hosted single server. To address this challenge, we propose ApplianceB ricks, a novel NFV-enable network appliance architecture that is used to explore the way of consolidating multiple physical network functions into a clustered network appliance, which is able to improve the processing capability of NFV-enabled network appliances.展开更多
基金supported by National Natural Science Foundation of China:Education Big Data Analysis based on Software Defined Networking Architecture(No.62177019,F0701)。
文摘The ultra-high speed,ultra-low latency,and massive connectivity of the 6 th Generation Mobile Network(6G)present unprecedented challenges to network security.In addition,the deep integration of Artificial Intelligence(AI)into 6G networks introduces AI-native features that further complicate the design and implementation of secure network architectures.To meet the security demands posed by the massive number of devices and edge nodes in 6G networks,a decentralized security architecture is essential,as it effectively mitigates the performance bottlenecks typically associated with centralized systems.Blockchain technology offers a promising trust mechanism among devices in 6G networks.However,conventional blockchain systems suffer from limited scalability under high-load conditions,making them inadequate for supporting a large volume of nodes and frequent data exchanges.To overcome these limitations,We propose Shard-DAG,a scalable architecture that structurally integrates Directed Acyclic Graphs(DAG)and sharding.Each shard adopts a Block-DAG structure for parallel block processing,effectively overcoming the performance bottlenecks of traditional chain-based blockchains.Furthermore,we introduce a DAG-based transaction ordering mechanism within each shard to defend against double-spending attacks.To ensure inter-shard security,Block-DAG adopts a black-box interaction approach to prevent cross-shard double-spending.Theoretical analysis and experimental evaluations demonstrate that Shard-DAG achieves near-linear scalability.In a network of 1,200 nodes with 8 shards,Shard-DAG achieves peak throughput improvements of 14.64 times over traditional blockchains,8.61 times over standalone BlockDAG,and 2.05 times over conventional sharded blockchains.The results validate Shard-DAG's ability to scale efficiently while maintaining robust security properties.
文摘Managing sensitive data in dynamic and high-stakes environments,such as healthcare,requires access control frameworks that offer real-time adaptability,scalability,and regulatory compliance.BIG-ABAC introduces a transformative approach to Attribute-Based Access Control(ABAC)by integrating real-time policy evaluation and contextual adaptation.Unlike traditional ABAC systems that rely on static policies,BIG-ABAC dynamically updates policies in response to evolving rules and real-time contextual attributes,ensuring precise and efficient access control.Leveraging decision trees evaluated in real-time,BIG-ABAC overcomes the limitations of conventional access control models,enabling seamless adaptation to complex,high-demand scenarios.The framework adheres to the NIST ABAC standard while incorporating modern distributed streaming technologies to enhance scalability and traceability.Its flexible policy enforcement mechanisms facilitate the implementation of regulatory requirements such as HIPAA and GDPR,allowing organizations to align access control policies with compliance needs dynamically.Performance evaluations demonstrate that BIG-ABAC processes 95% of access requests within 50 ms and updates policies dynamically with a latency of 30 ms,significantly outperforming traditional ABAC models.These results establish BIG-ABAC as a benchmark for adaptive,scalable,and context-aware access control,making it an ideal solution for dynamic,high-risk domains such as healthcare,smart cities,and Industrial IoT(IIoT).
基金supported in part by Multimedia University under the Research Fellow Grant MMUI/250008in part by Telekom Research&Development Sdn Bhd underGrantRDTC/241149Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2025R140),Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘The Internet of Things(IoT)ecosystem faces growing security challenges because it is projected to have 76.88 billion devices by 2025 and $1.4 trillion market value by 2027,operating in distributed networks with resource limitations and diverse system architectures.The current conventional intrusion detection systems(IDS)face scalability problems and trust-related issues,but blockchain-based solutions face limitations because of their low transaction throughput(Bitcoin:7 TPS(Transactions Per Second),Ethereum:15-30 TPS)and high latency.The research introduces MBID(Multi-Tier Blockchain Intrusion Detection)as a groundbreaking Multi-Tier Blockchain Intrusion Detection System with AI-Enhanced Detection,which solves the problems in huge IoT networks.The MBID system uses a four-tier architecture that includes device,edge,fog,and cloud layers with blockchain implementations and Physics-Informed Neural Networks(PINNs)for edge-based anomaly detection and a dual consensus mechanism that uses Honesty-based Distributed Proof-of-Authority(HDPoA)and Delegated Proof of Stake(DPoS).The system achieves scalability and efficiency through the combination of dynamic sharding and Interplanetary File System(IPFS)integration.Experimental evaluations demonstrate exceptional performance,achieving a detection accuracy of 99.84%,an ultra-low false positive rate of 0.01% with a False Negative Rate of 0.15%,and a near-instantaneous edge detection latency of 0.40 ms.The system demonstrated an aggregate throughput of 214.57 TPS in a 3-shard configuration,providing a clear,evidence-based path for horizontally scaling to support overmillions of devices with exceeding throughput.The proposed architecture represents a significant advancement in blockchain-based security for IoT networks,effectively balancing the trade-offs between scalability,security,and decentralization.
基金supported by the National Natural Science Foundation of China(Grant Nos.62422503,62105080,22004016,and U22A2093)the Guangdong Basic and Applied Basic Research Foundation Regional Joint Fund(Grant Nos.2023A1515011944,2020B1515130006,and 2021B515120056)+1 种基金the Talent Recruitment Project of Guangdong(Grant No.2021QN02X179)the Science and Technology Innovation Commission of Shenzhen(Grant Nos.JCYJ20220531095604009 and RCYX20221008092907027).
文摘Confronting the escalating global challenge of counterfeit products,developing advanced anticounterfeiting materials and structures with physical unclonable functions(PUFs)has become imperative.All-optical PUFs,distinguished by their high output complexity and expansive response space,offer a promising alternative to conventional electronic counterparts.For practical authentications,the expansion of optical PUF keys usually involves intricate spatial or spectral shaping of excitation light using bulky external apparatus,which largely hinders the applications of optical PUFs.Here,we report a plasmonic PUF system based on heterogeneous nanostructures.The template-assisted shadow deposition technique was employed to adjust the morphological diversity of densely packed metal nanoparticles in individual PUFs.Transmission images were processed via a hash algorithm,and the generated PUF keys with a scalable capacity from 2875 to 243401 exhibit excellent uniqueness,randomness,and reproducibility.Furthermore,the wavelength and the polarization state of the excitation light are harnessed as two distinct expanding strategies,offering the potential for multiscenario applications via a single PUF.Overall,our reported plasmonic PUFs operated with the multidimensional expanding strategy are envisaged to serve as easy-to-integrate,easy-to-use systems and promise efficacy across a broad spectrum of applications,from anticounterfeiting to data encryption and authentication.
文摘The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneously continues to elude most blockchain systems,often forcing trade-offs that limit their real-world applicability.This review paper synthesizes current research efforts aimed at resolving the trilemma,focusing on innovative consensus mechanisms,sharding techniques,layer-2 protocols,and hybrid architectural models.We critically analyze recent breakthroughs,including Directed Acyclic Graph(DAG)-based structures,cross-chain interoperability frameworks,and zero-knowledge proof(ZKP)enhancements,which aimto reconcile scalability with robust security and decentralization.Furthermore,we evaluate the trade-offs inherent in these approaches,highlighting their practical implications for enterprise adoption,decentralized finance(DeFi),and Web3 ecosystems.By mapping the evolving landscape of solutions,this review identifies gaps in currentmethodologies and proposes future research directions,such as adaptive consensus algorithms and artificial intelligence-driven(AI-driven)governance models.Our analysis underscores that while no universal solution exists,interdisciplinary innovations are progressively narrowing the trilemma’s constraints,paving the way for next-generation blockchain infrastructures.
基金This research was supported by ESIEA Paris through internal research resources provided by esieaLab LDR.
文摘The integration of the dynamic adaptive routing(DAR)algorithm in unmanned aerial vehicle(UAV)networks offers a significant advancement in addressing the challenges posed by next-generation communication systems like 6G.DAR’s innovative framework incorporates real-time path adjustments,energy-aware routing,and predictive models,optimizing reliability,latency,and energy efficiency in UAV operations.This study demonstrated DAR’s superior performance in dynamic,large-scale environments,proving its adaptability and scalability for real-time applications.As 6G networks evolve,challenges such as bandwidth demands,global spectrum management,security vulnerabilities,and financial feasibility become prominent.DAR aligns with these demands by offering robust solutions that enhance data transmission while ensuring network reliability.However,obstacles like global route optimization and signal interference in urban areas necessitate further refinement.Future directions should explore hybrid approaches,the integration of machine learning,and comprehensive real-world testing to maximize DAR’s capabilities.The findings underscore DAR’s pivotal role in enabling efficient and sustainable UAV communication systems,contributing to the broader landscape of wireless technology and laying a foundation for the seamless transition to 6G networks.
文摘A new scheme combining a scalable transcoder with space time block codes (STBC) for an orthogonal frequency division multiplexing (OFDM) system is proposed for robust video transmission in dispersive fading channels. The target application for such a scalable transcoder is to provide successful access to the pre-encoded high quality video MPEG-2 from mobile wireless terminals. In the scalable transcoder, besides outputting the MPEG-4 fine granular scalability (FGS) bitstream, both the size of video frames and the bit rate are reduced. And an array processing algorithm of layer interference suppression is used at the receiver which makes the system structure provide different levels of protection to different layers. Furthermore, by considering the important level of scalable bitstream, the different bitstreams can be given different level protection by the system structure and channel coding. With the proposed system, the concurrent large diversity gain characteristic of STBC and alleviation of the frequency-selective fading effect of OFDM can be achieved. The simulation results show that the proposed schemes integrating scalable transcoding can provide a basic quality of video transmission and outperform the conventional single layer transcoding transmitted under the random and bursty error channel conditions.
文摘Topology aggregation is necessary for scalable QoS routing mechanisms. Thekey issue is how to gain good performance while summarizing the topological information. In thispaper, we propose a new method to describe the logical link, which is simple and effective innetwork with additive and constrained concave parameters. We extend the method to network associatedwith multi-parameters. Furthermore, we propose a modified star aggregation algorithm. Simulationsare used to evaluate the performance. The results show that our algorithm is relatively good.
文摘针对区域防空反导作战中各要素复杂耦合所导致的战场态势快速演变、来袭目标数量动态变化等难题,提出一种基于可动态扩展且带时空推理的QMIX(QMIX with Dynamic extension and Spatiotemporal reasoning, QMIX-DS)的火力分配方法,以火力单元作为智能体构建决策网络,生成火力分配策略。核心改进为:为每个智能体的决策网络设计可动态扩展特征编码模块,自适应处理数量变化的来袭目标,并引入对比学习突出目标类别属性,形成差异化特征表征;构建两层多头自注意力机制捕捉不同类别目标间的动态时空依赖关系,快速推理任务过程中的态势演变,优化火力分配策略。基于墨子平台不同规模的仿真结果表明,所提出的火力分配方法能够在动态变化的战场条件下生成有效的防空反导策略,与基线算法及其他主流算法相比,所提QMIX-DS算法在目标拦截率、阵地存活率、导弹消耗数量等指标上均体现出了优势,并在不同场景中展现出较高的扩展性和泛化性。
基金supported in part by the Research Fund of Key Lab of Education Blockchain and Intelligent Technology,Ministry of Education(EBME25-F-08).
文摘Lightweight nodes are crucial for blockchain scalability,but verifying the availability of complete block data puts significant strain on bandwidth and latency.Existing data availability sampling(DAS)schemes either require trusted setups or suffer from high communication overhead and low verification efficiency.This paper presents ISTIRDA,a DAS scheme that lets light clients certify availability by sampling small random codeword symbols.Built on ISTIR,an improved Reed–Solomon interactive oracle proof of proximity,ISTIRDA combines adaptive folding with dynamic code rate adjustment to preserve soundness while lowering communication.This paper formalizes opening consistency and prove security with bounded error in the random oracle model,giving polylogarithmic verifier queries and no trusted setup.In a prototype compared with FRIDA under equal soundness,ISTIRDA reduces communication by 40.65%to 80%.For data larger than 16 MB,ISTIRDA verifies faster and the advantage widens;at 128 MB,proofs are about 60%smaller and verification time is roughly 25%shorter,while prover overhead remains modest.In peer-to-peer emulation under injected latency and loss,ISTIRDA reaches confidence more quickly and is less sensitive to packet loss and load.These results indicate that ISTIRDA is a scalable and provably secure DAS scheme suitable for high-throughput,large-block public blockchains,substantially easing bandwidth and latency pressure on lightweight nodes.
基金supported by the National Natural Science Foundation of China (Grant No.92576208)Tsinghua University Initiative Scientific Research Program+1 种基金Beijing Science and Technology Planning ProjectTsinghua University Dushi Program。
文摘Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom arrays,scalability is primarily constrained by the capacity to generate large numbers of optical tweezers,and conventional techniques using acousto-optic deflectors or spatial light modulators struggle to produce arrays much beyond∼10,000 tweezers.Moreover,these methods require additional microscope objectives to focus the light into micrometer-sized spots,which further complicates system integration and scalability.Here,we demonstrate the experimental generation of an optical tweezer array containing 280×280 spots using a metasurface,nearly an order of magnitude more than most existing systems.The metasurface leverages a large number of subwavelength phase-control pixels to engineer the wavefront of the incident light,enabling both large-scale tweezer generation and direct focusing into micron-scale spots without the need for a microscope.This result shifts the scalability bottleneck for atom arrays from the tweezer generation hardware to the available laser power.Furthermore,the array shows excellent intensity uniformity exceeding 90%,making it suitable for homogeneous single-atom loading and paving the way for trapping arrays of more than 10,000 atoms in the near future.
文摘This paper presents a novel full-chip scalable routing framework that simultaneously considers the routing congestion and the circuit performance. In order to bridge the gap, the presented framework calls the detailed router immediately after a global route is extracted. With the interleaving mode of global routing immediately followed by detailed routing, accurate routing resource and congestion information can be obtained, which provides valuable guidance for the following global routing process. The framework features the fast pattern and framed shortest path global router,a maze-based congestion-driven detailed router, and better interaction between the two routers. In the framework, timing critical nets can be assigned higher priority for performance concern, and different net ordering techniques can be adopted for different routing objectives. The framework is tested on a set of commonly used benchmark circuits and compared with a previous multilevel routing framework. Experimental results show that the presented framework obtains significantly better routing solutions than the previous one considering circuit performance, routing completion rate, and runtime.
文摘The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC. Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL) and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, in- cluding the design criteria, use cases, signaling and payload structure.
基金supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (Grant No. 2016YFB0800100, No. 2016YFB0800101)the National Natural Science Foundation of China (Grant No. 61521003)the National Key R&D Program of China (Grant No. 61309020)
文摘Dynamic Controller Provisioning Problem(DCPP) is a key problem for scalable SDN. Previously, the solution to this problem focused on adapting the number of controllers and their locations with changing network conditions, but ignored balancing control loads via switch migration. In this paper, we study a scalable control mechanism to decide which switch and where it should be migrated for more balanced control plane, and we define it as Switch Migration Problem(SMP). The main contributions of this paper are as follows. First, we define a SDN model to describe the relation between controllers and switches from the view of loads. Based on this model, we form SMP as a Network Utility Maximization(NUM) problem with the objective of serving more requests under available control resources. Second, we design a synthesizing distributed algorithm for SMP--- Distributed Hopping Algorithm(DHA), by approximating our optimal objective via Log-Sum-Exp function. In DHA, individual controller performs algorithmic procedure independently. With the solution space F, we prove that the optimal gap caused by approximation is at most 1/βlog|F|, and DHA procedure is equal to implementation of a time-reversible Markov Chain process. Finally, the results are corroborated by several numerical simulations.
基金supported by Program for National Basic Research Program of China (973 Program) "Reconfigurable Network Emulation Testbed for Basic Network Communication"
文摘Network Functions Virtualization(NFV) is an attempt to help operators more effectively manage their networks by implementing traditional network functions embedded in specialized hardware platforms in term of virtualized software instances. But, existing novel network appliances designed for NFV infrastructure are always architected on a general-purpose x86 server, which makes the performance of network functions limited by the hosted single server. To address this challenge, we propose ApplianceB ricks, a novel NFV-enable network appliance architecture that is used to explore the way of consolidating multiple physical network functions into a clustered network appliance, which is able to improve the processing capability of NFV-enabled network appliances.