In order to incorporate smart elements into distribution networks at ITELCA laboratories in Bogotá-Colombia, a Machine-to-Machine-based solution has been developed. This solution aids in the process of low-cost e...In order to incorporate smart elements into distribution networks at ITELCA laboratories in Bogotá-Colombia, a Machine-to-Machine-based solution has been developed. This solution aids in the process of low-cost electrical fault location, which contributes to improving quality of service, particularly by shortening interruption time spans in mid-voltage grids. The implementation makes use of MQTT protocol with an intensive use of Internet of things (IoT) environment which guarantees the following properties within the automation process: Advanced reports and statistics, remote command execution on one or more units (groups of units), detailed monitoring of remote units and custom alarm mechanism and firmware upgrade on one or more units (groups of units). This kind of implementation is the first one in Colombia and it is able to automatically recover from an N-1 fault.展开更多
With the rapid development of the sixth generation(6G)network and Internet of Things(IoT),it has become extremely challenging to efficiently detect and prevent the distributed denial of service(DDoS)attacks originatin...With the rapid development of the sixth generation(6G)network and Internet of Things(IoT),it has become extremely challenging to efficiently detect and prevent the distributed denial of service(DDoS)attacks originating from IoT devices.In this paper we propose an innovative trust model for IoT devices to prevent potential DDoS attacks by evaluating their trustworthiness,which can be deployed in the access network of 6G IoT.Based on historical communication behaviors,this model combines spatial trust and temporal trust values to comprehensively characterize the normal behavior patterns of IoT devices,thereby effectively distinguishing attack traffic.Experimental results show that the proposed method can efficiently distinguish normal traffic from DDoS traffic.Compared with the benchmark methods,our method has advantages in terms of both accuracy and efficiency in identifying attack flows.展开更多
The important issues of network TCP congestion control are how to compute the link price according to the link status and regulate the data sending rate based on link congestion pricing feedback information.However,it...The important issues of network TCP congestion control are how to compute the link price according to the link status and regulate the data sending rate based on link congestion pricing feedback information.However,it is difficult to predict the congestion state of the link-end accurately at the source.In this paper,we presented an improved NUMFabric algorithm for calculating the overall congestion price.In the proposed scheme,the whole network structure had been obtained by the central control server in the Software Defined Network,and a kind of dual-hierarchy algorithm for calculating overall network congestion price had been demonstrated.In this scheme,the first hierarchy algorithm was set up in a central control server like Opendaylight and the guiding parameter B is obtained based on the intelligent data of global link state information.Based on the historical data,the congestion state of the network and the guiding parameter B is accurately predicted by the machine learning algorithm.The second hierarchy algorithm was installed in the Openflow link and the link price was calculated based on guiding parameter B given by the first algorithm.We evaluate this evolved NUMFabric algorithm in NS3,which demonstrated that the proposed NUMFabric algorithm could efficiently increase the link bandwidth utilization of cloud computing IoT datacenters.展开更多
Blockchain has recently sparked interest in both the technological and businessfirms.The Internet of Things's(IoT)core principle emerged due to the connectivity of several new technologies,including wireless techno...Blockchain has recently sparked interest in both the technological and businessfirms.The Internet of Things's(IoT)core principle emerged due to the connectivity of several new technologies,including wireless technology,the Inter-net,embedded automation systems,and micro-electromechanical devices.Manu-facturing environments and operations have been successfully converted by implementing recent advanced technology like Cloud Computing(CC),Cyber-Physical System(CSP),Information and Communication Technologies(ICT)and Enterprise Model,and other technological innovations into the fourth indus-trial revolution referred to as Industry 4.0.Data management is defined as the pro-cess of accumulation in order to make better business decisions,and process,secure and store information about a company.In the incipient model,there are interconnected contrivances and Machine-to-Machine(M2M)interactions,and transaction data are stored on the Blockchain.Security is a challenging aspect that must be punctiliously considered during the design and development phases of a CSP.In this research article,we proposed a Secure and Distributed Framework for Resource Management(SDFRM)in Industry 4.0 environments within a distribu-ted and collaborative Industry 4.0 system,the dynamic and trust-based Distributed Management Framework(DMF)of shared resource access.Such issues are focused by taking into account of the traditional characteristics of IoT/Industrial Internet of Things’(IIoT)-predicated environments,an SDFRM in Industry 4.0 environments within a distributed and collaborative Industry 4.0 system.Also,to ensure strong privacy over the procedures associated with Access Control(AC),a privacy-preserving method is proposed and integrated into the DMF.The proposed DMF,based on blockchain technology and peer-to-peer networks,allows dynamic access management and system governance without using third parties who could be attacked.We worked hard to design and implement the pro-posal to demonstrate its viability and evaluate its performance.Our proposal out-performs the Multichain Blockchain in terms of successful storage transactions with an achieved average throughput of 98.15%.展开更多
The Internet of Things(IoT)consists of interconnected smart devices communicating and collecting data.The Routing Protocol for Low-Power and Lossy Networks(RPL)is the standard protocol for Internet Protocol Version 6(...The Internet of Things(IoT)consists of interconnected smart devices communicating and collecting data.The Routing Protocol for Low-Power and Lossy Networks(RPL)is the standard protocol for Internet Protocol Version 6(IPv6)in the IoT.However,RPL is vulnerable to various attacks,including the sinkhole attack,which disrupts the network by manipulating routing information.This paper proposes the Unweighted Voting Method(UVM)for sinkhole node identification,utilizing three key behavioral indicators:DODAG Information Object(DIO)Transaction Frequency,Rank Harmony,and Power Consumption.These indicators have been carefully selected based on their contribution to sinkhole attack detection and other relevant features used in previous research.The UVM method employs an unweighted voting mechanism,where each voter or rule holds equal weight in detecting the presence of a sinkhole attack based on the proposed indicators.The effectiveness of the UVM method is evaluated using the COOJA simulator and compared with existing approaches.Notably,the proposed approach fulfills power consumption requirements for constrained nodes without increasing consumption due to the deployment design.In terms of detection accuracy,simulation results demonstrate a high detection rate ranging from 90%to 100%,with a low false-positive rate of 0%to 0.2%.Consequently,the proposed approach surpasses Ensemble Learning Intrusion Detection Systems by leveraging three indicators and three supporting rules.展开更多
The proliferation of Internet of Things(IoT)devices that operate unattended providing a multitude of important and often sensitive services highlights the need for seamless interoperability and increased security.We a...The proliferation of Internet of Things(IoT)devices that operate unattended providing a multitude of important and often sensitive services highlights the need for seamless interoperability and increased security.We argue that digital twins of IoT devices,with the right design,can enhance the security,reliability,auditability,and interoperability of IoT systems.The salient features of digital twins have made them key elements for the IoT and Industry 4.0.In this paper,we leverage advances in W3C’s Web of Things(WoT)standards and distributed ledger technologies(DLTs)to present a novel design of the smart contract-based digital twins with enhanced security,transparency,interoperability,and reliability.We provide two different variations of that general design using two different blockchains(one public and one private,permissioned blockchain),and we present design trade-offs.Furthermore,we introduce an architecture for accessing and controlling IoT devices securely and reliably,providing full auditability,while at the same time using the proposed digital twins as an indirection mechanism(proxy).The proposed architecture leverages the blockchain to offer notable properties,namely,decentralization,immutability,auditability,non-repudiation,availability,and reliability.Moreover,it introduces mass actuation,easier management of IoT devices,and enhanced security to the IoT gateways,enables new business models,and makes consumer devices(vendor-)agnostic.展开更多
The rapid development of Internet Plus Smart Energy requires further strengthening of three kinds of interconnections based on traditional power systems: physical interconnection, information interconnection, and comm...The rapid development of Internet Plus Smart Energy requires further strengthening of three kinds of interconnections based on traditional power systems: physical interconnection, information interconnection, and commercial interconnection. Due to the integration of renewable energy, the reform of the electricity market, and the deployment of the Smart Grid, a large amount of data will be generated. Thus, it is necessary to establish a Ubiquitous Power Internet of Things (UPIoT) to realize connections among people and things, things and things, and people and people in power systems. This paper studies the concept and architecture of the UPIoT and indicates the deployment of the perception layer and network layer as the key to building UPIoT in the initial stage. As UPIoT tends to cover a wide area and produce massive and distributed data, signal processing and data analytics theories and techniques are needed to handle the data and observe the state of the large-scale system. Further studies on distributed sensing and cooperative estimation theories and techniques of UPIoT are also required. Finally, the application prospects of UPIoT and the directions for future research are discussed.展开更多
Wireless Sensor Networks(WSNs) have many applications, such as climate monitoring systems, fire detection, smart homes, and smart cities. It is expected that WSNs will be integrated into the Internet of Things(IoT...Wireless Sensor Networks(WSNs) have many applications, such as climate monitoring systems, fire detection, smart homes, and smart cities. It is expected that WSNs will be integrated into the Internet of Things(IoT)and participate in various tasks. WSNs play an important role monitoring and reporting environment information and collecting surrounding context. In this paper we consider a WSN deployed for an application such as environment monitoring, and a mobile sink which acts as the gateway between the Internet and the WSN. Data gathering is a challenging problem in WSNs and in the IoT because the information has to be available quickly and effectively without delays and redundancies. In this paper we propose several distributed algorithms for composite event detection and reporting to a mobile sink. Once data is collected by the sink, it can be shared using the IoT infrastructure. We analyze the performance of our algorithms using WSNet simulator, which is specially designed for event-based WSNs. We measure various metrics such as average residual energy, percentage of composite events processed successfully at the sink, and the average number of hops to reach the sink.展开更多
This paper advocates the use of the distributed compressed sensing(DCS)paradigm to deploy energy harvesting(EH)Internet of Thing(IoT)devices for energy self-sustainability.We consider networks with signal/energy model...This paper advocates the use of the distributed compressed sensing(DCS)paradigm to deploy energy harvesting(EH)Internet of Thing(IoT)devices for energy self-sustainability.We consider networks with signal/energy models that capture the fact that both the collected signals and the harvested energy of different devices can exhibit correlation.We provide theoretical analysis on the performance of both the classical compressive sensing(CS)approach and the proposed distributed CS(DCS)-based approach to data acquisition for EH IoT.Moreover,we perform an in-depth comparison of the proposed DCSbased approach against the distributed source coding(DSC)system.These performance characterizations and comparisons embody the effect of various system phenomena and parameters including signal correlation,EH correlation,network size,and energy availability level.Our results unveil that,the proposed approach offers significant increase in data gathering capability with respect to the CS-based approach,and offers a substantial reduction of the mean-squared error distortion with respect to the DSC system.展开更多
The objective of this paper is to provide a robust Virtual Power Plant(VPP)network collaborated with Internet of Things(IoT)which uses a conceptual model to integrate each device in the grid.Based on the functionality...The objective of this paper is to provide a robust Virtual Power Plant(VPP)network collaborated with Internet of Things(IoT)which uses a conceptual model to integrate each device in the grid.Based on the functionality all the devices which are purely distributed within the grid are networked initially from residential units to substations and up to service data and demand centres.To ensure the trapping of the available power and the efficient transfer of Distributed Generation(DG)power to the grid Distribution Active Control(DAC)strategy is used.Synchronized optimization of DG parameter which includes DG size,location and type are adopted using Dispatch strategy.The case studies are optimized by rescheduling the generation and with load curtailment.Maximized Customer Benefit(MCB)is taken as an objective function and a straight forward solution is given by heuristic search techniques.This method was vindicated in a practical Indian Utility system.This control proposes better performances,ensures reliability and efficiency even under parameter variations along with disturbances which is justified using IEEE 118 bus system and real time Indian utility 63 bus system.Results reveal that the proposed technique proves advantages of low computational intricacy.展开更多
针对数据量剧增的配电物联网中存在的带宽利用率低和业务数据服务质量(quality of service,QoS)难以满足通信需求等问题,提出一种多优先级排队论的带宽分配方法。首先,对感知终端到边缘物联网关的业务数据传输过程进行改进,改进后的传...针对数据量剧增的配电物联网中存在的带宽利用率低和业务数据服务质量(quality of service,QoS)难以满足通信需求等问题,提出一种多优先级排队论的带宽分配方法。首先,对感知终端到边缘物联网关的业务数据传输过程进行改进,改进后的传输过程可根据不同业务数据对QoS的不同要求进行数据优先级的划分,对不同优先级数据设置不同的服务机制;然后,对业务数据传输中的马尔科夫过程进行分析,基于改进后的数据传输过程建立以带宽利用率为目标,丢包率和延时时间为约束的多优先级排队论带宽分配模型;并将所提出的带宽分配方法与传统方法进行对比。结果表明:QoS指标有所改善,而且带宽利用率比传统不分优先级带宽分配方法高9.73%,比弹性系数法高31.17%。最后,探究多优先级排队论带宽分配方法的动态性能,结果表明适当地提高带宽可以改善QoS指标,但要注意带宽增大时所带来的带宽利用率减小问题。合理的带宽分配可以避免资源的浪费。展开更多
Active distribution network(ADN),as a typically cyber-physical system,develops with the evolution of Internet of Things(IoTs),which makes the network vulnerable to cybersecurity threats.In this paper,the eavesdropping...Active distribution network(ADN),as a typically cyber-physical system,develops with the evolution of Internet of Things(IoTs),which makes the network vulnerable to cybersecurity threats.In this paper,the eavesdropping attacks that lead to privacy breaches are addressed for the IoT-enabled ADN.A privacy-preserving energy management system(EMS)is proposed and empowered by secure data exchange protocols based on the homomorphic cryptosystem.During the information transmission among distributed generators and load customers in the EMS,private information including power usage and electricity bidding price can be effectively protected against eavesdropping attacks.The correctness of the final solutions,e.g.,optimal market clearing price and unified power utilization ratio,can be deterministically guaranteed.The simulation results demonstrate the effectiveness and the computational efficiency of the proposed homomorphically encrypted EMS.展开更多
文摘In order to incorporate smart elements into distribution networks at ITELCA laboratories in Bogotá-Colombia, a Machine-to-Machine-based solution has been developed. This solution aids in the process of low-cost electrical fault location, which contributes to improving quality of service, particularly by shortening interruption time spans in mid-voltage grids. The implementation makes use of MQTT protocol with an intensive use of Internet of things (IoT) environment which guarantees the following properties within the automation process: Advanced reports and statistics, remote command execution on one or more units (groups of units), detailed monitoring of remote units and custom alarm mechanism and firmware upgrade on one or more units (groups of units). This kind of implementation is the first one in Colombia and it is able to automatically recover from an N-1 fault.
基金This work was supported in part by the National Key R&D Program of China under Grant 2020YFA0711301in part by the National Natural Science Foundation of China under Grant 61922049,and Grant 61941104in part by the Tsinghua University-China Mobile Communications Group Company Ltd.,Joint Institute.
文摘With the rapid development of the sixth generation(6G)network and Internet of Things(IoT),it has become extremely challenging to efficiently detect and prevent the distributed denial of service(DDoS)attacks originating from IoT devices.In this paper we propose an innovative trust model for IoT devices to prevent potential DDoS attacks by evaluating their trustworthiness,which can be deployed in the access network of 6G IoT.Based on historical communication behaviors,this model combines spatial trust and temporal trust values to comprehensively characterize the normal behavior patterns of IoT devices,thereby effectively distinguishing attack traffic.Experimental results show that the proposed method can efficiently distinguish normal traffic from DDoS traffic.Compared with the benchmark methods,our method has advantages in terms of both accuracy and efficiency in identifying attack flows.
基金supported by National Key R&D Program of China—Industrial Internet Application Demonstration-Sub-topic Intelligent Network Operation and Security Protection(2018YFB1802400).
文摘The important issues of network TCP congestion control are how to compute the link price according to the link status and regulate the data sending rate based on link congestion pricing feedback information.However,it is difficult to predict the congestion state of the link-end accurately at the source.In this paper,we presented an improved NUMFabric algorithm for calculating the overall congestion price.In the proposed scheme,the whole network structure had been obtained by the central control server in the Software Defined Network,and a kind of dual-hierarchy algorithm for calculating overall network congestion price had been demonstrated.In this scheme,the first hierarchy algorithm was set up in a central control server like Opendaylight and the guiding parameter B is obtained based on the intelligent data of global link state information.Based on the historical data,the congestion state of the network and the guiding parameter B is accurately predicted by the machine learning algorithm.The second hierarchy algorithm was installed in the Openflow link and the link price was calculated based on guiding parameter B given by the first algorithm.We evaluate this evolved NUMFabric algorithm in NS3,which demonstrated that the proposed NUMFabric algorithm could efficiently increase the link bandwidth utilization of cloud computing IoT datacenters.
文摘Blockchain has recently sparked interest in both the technological and businessfirms.The Internet of Things's(IoT)core principle emerged due to the connectivity of several new technologies,including wireless technology,the Inter-net,embedded automation systems,and micro-electromechanical devices.Manu-facturing environments and operations have been successfully converted by implementing recent advanced technology like Cloud Computing(CC),Cyber-Physical System(CSP),Information and Communication Technologies(ICT)and Enterprise Model,and other technological innovations into the fourth indus-trial revolution referred to as Industry 4.0.Data management is defined as the pro-cess of accumulation in order to make better business decisions,and process,secure and store information about a company.In the incipient model,there are interconnected contrivances and Machine-to-Machine(M2M)interactions,and transaction data are stored on the Blockchain.Security is a challenging aspect that must be punctiliously considered during the design and development phases of a CSP.In this research article,we proposed a Secure and Distributed Framework for Resource Management(SDFRM)in Industry 4.0 environments within a distribu-ted and collaborative Industry 4.0 system,the dynamic and trust-based Distributed Management Framework(DMF)of shared resource access.Such issues are focused by taking into account of the traditional characteristics of IoT/Industrial Internet of Things’(IIoT)-predicated environments,an SDFRM in Industry 4.0 environments within a distributed and collaborative Industry 4.0 system.Also,to ensure strong privacy over the procedures associated with Access Control(AC),a privacy-preserving method is proposed and integrated into the DMF.The proposed DMF,based on blockchain technology and peer-to-peer networks,allows dynamic access management and system governance without using third parties who could be attacked.We worked hard to design and implement the pro-posal to demonstrate its viability and evaluate its performance.Our proposal out-performs the Multichain Blockchain in terms of successful storage transactions with an achieved average throughput of 98.15%.
基金funded by the Deanship of Scientific Research at Najran University for this research through a Grant(NU/RG/SERC/12/50)under the Research Groups at Najran University,Saudi Arabia.
文摘The Internet of Things(IoT)consists of interconnected smart devices communicating and collecting data.The Routing Protocol for Low-Power and Lossy Networks(RPL)is the standard protocol for Internet Protocol Version 6(IPv6)in the IoT.However,RPL is vulnerable to various attacks,including the sinkhole attack,which disrupts the network by manipulating routing information.This paper proposes the Unweighted Voting Method(UVM)for sinkhole node identification,utilizing three key behavioral indicators:DODAG Information Object(DIO)Transaction Frequency,Rank Harmony,and Power Consumption.These indicators have been carefully selected based on their contribution to sinkhole attack detection and other relevant features used in previous research.The UVM method employs an unweighted voting mechanism,where each voter or rule holds equal weight in detecting the presence of a sinkhole attack based on the proposed indicators.The effectiveness of the UVM method is evaluated using the COOJA simulator and compared with existing approaches.Notably,the proposed approach fulfills power consumption requirements for constrained nodes without increasing consumption due to the deployment design.In terms of detection accuracy,simulation results demonstrate a high detection rate ranging from 90%to 100%,with a low false-positive rate of 0%to 0.2%.Consequently,the proposed approach surpasses Ensemble Learning Intrusion Detection Systems by leveraging three indicators and three supporting rules.
文摘The proliferation of Internet of Things(IoT)devices that operate unattended providing a multitude of important and often sensitive services highlights the need for seamless interoperability and increased security.We argue that digital twins of IoT devices,with the right design,can enhance the security,reliability,auditability,and interoperability of IoT systems.The salient features of digital twins have made them key elements for the IoT and Industry 4.0.In this paper,we leverage advances in W3C’s Web of Things(WoT)standards and distributed ledger technologies(DLTs)to present a novel design of the smart contract-based digital twins with enhanced security,transparency,interoperability,and reliability.We provide two different variations of that general design using two different blockchains(one public and one private,permissioned blockchain),and we present design trade-offs.Furthermore,we introduce an architecture for accessing and controlling IoT devices securely and reliably,providing full auditability,while at the same time using the proposed digital twins as an indirection mechanism(proxy).The proposed architecture leverages the blockchain to offer notable properties,namely,decentralization,immutability,auditability,non-repudiation,availability,and reliability.Moreover,it introduces mass actuation,easier management of IoT devices,and enhanced security to the IoT gateways,enables new business models,and makes consumer devices(vendor-)agnostic.
基金Supported by National Key Research and DevelopmentProgram of China(2016YFB0900100).
文摘The rapid development of Internet Plus Smart Energy requires further strengthening of three kinds of interconnections based on traditional power systems: physical interconnection, information interconnection, and commercial interconnection. Due to the integration of renewable energy, the reform of the electricity market, and the deployment of the Smart Grid, a large amount of data will be generated. Thus, it is necessary to establish a Ubiquitous Power Internet of Things (UPIoT) to realize connections among people and things, things and things, and people and people in power systems. This paper studies the concept and architecture of the UPIoT and indicates the deployment of the perception layer and network layer as the key to building UPIoT in the initial stage. As UPIoT tends to cover a wide area and produce massive and distributed data, signal processing and data analytics theories and techniques are needed to handle the data and observe the state of the large-scale system. Further studies on distributed sensing and cooperative estimation theories and techniques of UPIoT are also required. Finally, the application prospects of UPIoT and the directions for future research are discussed.
文摘Wireless Sensor Networks(WSNs) have many applications, such as climate monitoring systems, fire detection, smart homes, and smart cities. It is expected that WSNs will be integrated into the Internet of Things(IoT)and participate in various tasks. WSNs play an important role monitoring and reporting environment information and collecting surrounding context. In this paper we consider a WSN deployed for an application such as environment monitoring, and a mobile sink which acts as the gateway between the Internet and the WSN. Data gathering is a challenging problem in WSNs and in the IoT because the information has to be available quickly and effectively without delays and redundancies. In this paper we propose several distributed algorithms for composite event detection and reporting to a mobile sink. Once data is collected by the sink, it can be shared using the IoT infrastructure. We analyze the performance of our algorithms using WSNet simulator, which is specially designed for event-based WSNs. We measure various metrics such as average residual energy, percentage of composite events processed successfully at the sink, and the average number of hops to reach the sink.
基金This work has been supported by the National Key R&D Program of China(Grant No.2018YFE0207600)EPSRC Research Grant(EP/K033700/1,EP/K033166/1)+2 种基金the Natural Science Foundation of China(61671046,61911530216,U1834210)the Beijing Natural Science Foundation(4182050)the FWO(Grants G0A2617N and G093817N).
文摘This paper advocates the use of the distributed compressed sensing(DCS)paradigm to deploy energy harvesting(EH)Internet of Thing(IoT)devices for energy self-sustainability.We consider networks with signal/energy models that capture the fact that both the collected signals and the harvested energy of different devices can exhibit correlation.We provide theoretical analysis on the performance of both the classical compressive sensing(CS)approach and the proposed distributed CS(DCS)-based approach to data acquisition for EH IoT.Moreover,we perform an in-depth comparison of the proposed DCSbased approach against the distributed source coding(DSC)system.These performance characterizations and comparisons embody the effect of various system phenomena and parameters including signal correlation,EH correlation,network size,and energy availability level.Our results unveil that,the proposed approach offers significant increase in data gathering capability with respect to the CS-based approach,and offers a substantial reduction of the mean-squared error distortion with respect to the DSC system.
文摘The objective of this paper is to provide a robust Virtual Power Plant(VPP)network collaborated with Internet of Things(IoT)which uses a conceptual model to integrate each device in the grid.Based on the functionality all the devices which are purely distributed within the grid are networked initially from residential units to substations and up to service data and demand centres.To ensure the trapping of the available power and the efficient transfer of Distributed Generation(DG)power to the grid Distribution Active Control(DAC)strategy is used.Synchronized optimization of DG parameter which includes DG size,location and type are adopted using Dispatch strategy.The case studies are optimized by rescheduling the generation and with load curtailment.Maximized Customer Benefit(MCB)is taken as an objective function and a straight forward solution is given by heuristic search techniques.This method was vindicated in a practical Indian Utility system.This control proposes better performances,ensures reliability and efficiency even under parameter variations along with disturbances which is justified using IEEE 118 bus system and real time Indian utility 63 bus system.Results reveal that the proposed technique proves advantages of low computational intricacy.
文摘针对数据量剧增的配电物联网中存在的带宽利用率低和业务数据服务质量(quality of service,QoS)难以满足通信需求等问题,提出一种多优先级排队论的带宽分配方法。首先,对感知终端到边缘物联网关的业务数据传输过程进行改进,改进后的传输过程可根据不同业务数据对QoS的不同要求进行数据优先级的划分,对不同优先级数据设置不同的服务机制;然后,对业务数据传输中的马尔科夫过程进行分析,基于改进后的数据传输过程建立以带宽利用率为目标,丢包率和延时时间为约束的多优先级排队论带宽分配模型;并将所提出的带宽分配方法与传统方法进行对比。结果表明:QoS指标有所改善,而且带宽利用率比传统不分优先级带宽分配方法高9.73%,比弹性系数法高31.17%。最后,探究多优先级排队论带宽分配方法的动态性能,结果表明适当地提高带宽可以改善QoS指标,但要注意带宽增大时所带来的带宽利用率减小问题。合理的带宽分配可以避免资源的浪费。
基金supported by the National Natural Science Foundation of China(No.52077188)Guangdong Science and Technology Department(No.2019A1515011226)Hong Kong Research Grant Council(No.15219619).
文摘Active distribution network(ADN),as a typically cyber-physical system,develops with the evolution of Internet of Things(IoTs),which makes the network vulnerable to cybersecurity threats.In this paper,the eavesdropping attacks that lead to privacy breaches are addressed for the IoT-enabled ADN.A privacy-preserving energy management system(EMS)is proposed and empowered by secure data exchange protocols based on the homomorphic cryptosystem.During the information transmission among distributed generators and load customers in the EMS,private information including power usage and electricity bidding price can be effectively protected against eavesdropping attacks.The correctness of the final solutions,e.g.,optimal market clearing price and unified power utilization ratio,can be deterministically guaranteed.The simulation results demonstrate the effectiveness and the computational efficiency of the proposed homomorphically encrypted EMS.