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AdaptNF: Adaptive service chain scheduling with stateless migration and NF consolidation
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作者 Qing Li He Huang +1 位作者 Yong Jiang Jingpu Duan 《Digital Communications and Networks》 SCIE CSCD 2023年第2期462-472,共11页
The combination of network function virtualization and software-defined networking allows various network functions to process flows according to their characteristics and requirements.Due to the highly dynamic nature... The combination of network function virtualization and software-defined networking allows various network functions to process flows according to their characteristics and requirements.Due to the highly dynamic nature of the workload,the network infrastructure needs to properly schedule the underlying resources in order to respond to workload changes in a timely manner.However,the existing NFV platform lacks a comprehensive solution for how to scale under workload variation,which may seriously hurt the overall system performance.To improve the scalability of the NFV platform and ensure consistent high performance under dynamic workloads,we propose AdaptNF,a novel NFV platform designed to support a combination of course-grained and fine-grained resource scheduling strategies.To deal with resource imbalance,which is the essential scheduling problem that leads to insufficient NFV performance,AdaptNF adopts a novel algorithm that can efficiently balance the workload among multiple network function instances through stateless flow migration.Our controlled experiments show that the AdaptNF scheme can optimize resource allocation and ensure outstanding performance after scaling.In terms of network throughput and latency,AdaptNF significantly improves the performance of the underlying NFV platform. 展开更多
关键词 Network function virtualization Software-defined networking service chain Flow migration Dynamic scale
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Service Function Chain Migration in LEO Satellite Networks
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作者 Geng Yuhui Wang Niwei +5 位作者 Chen Xi Xu Xiaofan Zhou Changsheng Yang Junyi Xiao Zhenyu Cao Xianbin 《China Communications》 SCIE CSCD 2024年第3期247-259,共13页
With the advancements of software defined network(SDN)and network function virtualization(NFV),service function chain(SFC)placement becomes a crucial enabler for flexible resource scheduling in low earth orbit(LEO)sat... With the advancements of software defined network(SDN)and network function virtualization(NFV),service function chain(SFC)placement becomes a crucial enabler for flexible resource scheduling in low earth orbit(LEO)satellite networks.While due to the scarcity of bandwidth resources and dynamic topology of LEO satellites,the static SFC placement schemes may cause performance degradation,resource waste and even service failure.In this paper,we consider migration and establish an online migration model,especially considering the dynamic topology.Given the scarcity of bandwidth resources,the model aims to maximize the total number of accepted SFCs while incurring as little bandwidth cost of SFC transmission and migration as possible.Due to its NP-hardness,we propose a heuristic minimized dynamic SFC migration(MDSM)algorithm that only triggers the migration procedure when new SFCs are rejected.Simulation results demonstrate that MDSM achieves a performance close to the upper bound with lower complexity. 展开更多
关键词 network function virtualization(NFV) resource allocation satellite networks service function chain(SFC) SFC migration SFC placement soft-ware defined network(SDN)
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Evolutionary PSO-based emergency monitoring geospatial edge service chain in the emergency communication network
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作者 Sheng He Xicheng Tan +4 位作者 Yanfei Zhong Meng Huang Zhiyuan Mei You Wan Huaming Wang 《International Journal of Digital Earth》 SCIE EI 2023年第1期2797-2817,共21页
Emergency communication networks play a vital role in disaster monitoring,transmission,and application during disaster emergency response(DER),however,the performance and stability of edge nodes in the emergency commu... Emergency communication networks play a vital role in disaster monitoring,transmission,and application during disaster emergency response(DER),however,the performance and stability of edge nodes in the emergency communication networks are often weak due to limited communication and computation resources.This weakness directly affects the quality,of service(Qos)of the geospatial edge service(GES)chains involved in emergency monitoring.Existing research predominantly addresses service compositions in stable environments,neglecting the aggregation of efficient and robust GES chains in emergency communication networks.This study proposes an evolutionary_particie swarm optimization(EPSO)-based emergency monitoring GES chain in an_emergency communication network.it includes a GES chain model of emergency environment monitoring for tailing areas,as well as the designs of the particle chromosome encoding method,fitness evaluation model,and particle chromosome swarm update operators of the EPSO-based GES chain.Finally,the study conducts emergency environment monitoring experiments for tailing areas using the proposed method.Experiments results demonstrate that the proposed method significantly enhances the efficiency,stability,and reliability of emergency monitoring GEs chains in the emergency communication network.This is crucial to providing fast and reliable services for DER during natural disasters. 展开更多
关键词 Edge computing emergency communication emergency monitoring evolutionary computation geospatiai service chain PSO
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Formal verification technique for grid service chain model and its application 被引量:2
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作者 XU Ke WANG YueXuan WU Cheng 《Science in China(Series F)》 2007年第1期1-20,共20页
Ensuring the correctness and reliability of large-scale resource sharing and complex job processing Is an Important task for grid applications. From a formal method perspective, a grid service chain model based on sta... Ensuring the correctness and reliability of large-scale resource sharing and complex job processing Is an Important task for grid applications. From a formal method perspective, a grid service chain model based on state PI calculus Is proposed In this work as the theoretical foundation for the service composition and collaboration in grid. Following the Idea of the Web Service Resource Framework (WSRF), state PI calculus enables the life-cycle management of system states by associating the actions in the original PI calculus with system states. Moreover, model checking technique is exploltad for the design-time and run-time logical verification of grid service chain models. A grid application scenario of the dynamic analysis of material deformation structure is also provided to show the effectiveness of the proposed work. 展开更多
关键词 GRID grid service chain formal method model checking state Pi calculus
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Universal workflow-based high performance geo-computation service chain platform 被引量:1
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作者 Fang Huang Hao Yang +1 位作者 Jian Tao Qiang Zhu 《Big Earth Data》 EI 2020年第4期409-434,共26页
Based on web services and the Activiti 5.0 workflow engine,we built a workflow-based web service chain processing flow platform to simplify the operations of complex geospatial information processing applications in t... Based on web services and the Activiti 5.0 workflow engine,we built a workflow-based web service chain processing flow platform to simplify the operations of complex geospatial information processing applications in the area of high performance geocomputation.The proposed framework includes a web portal and a convenient mode for similar specific applications.We also designed a general service publishing template for high performance commutating(HPC)that can reduce platform differences among different HPC systems and facilitate HPC techniques to improve processing efficiency.Finally,we used a digital elevation model to verify and test the platform.The results indicated that the proposed service chain platform offered convenience and efficiency when processing massive data with HPC. 展开更多
关键词 High performance geo-computation WORKFLOW web service service chain platform geospatial information processing
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基于SDN的动态ServiceChaining方案
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作者 林鹏 《信息与电脑》 2020年第18期153-157,共5页
随着终端规模的不断增加和云计算的逐渐普及,园区网的业务越来越多样化,从而带来网络容量和带宽升级。基础网络升级后,园区边缘网络的专用设备(防火墙、广域网加速设备等)容易成为整个园区网的性能瓶颈点。而对这些专用设备进行升级和... 随着终端规模的不断增加和云计算的逐渐普及,园区网的业务越来越多样化,从而带来网络容量和带宽升级。基础网络升级后,园区边缘网络的专用设备(防火墙、广域网加速设备等)容易成为整个园区网的性能瓶颈点。而对这些专用设备进行升级和更换所带来的支出费用较大,同时由于这些设备都是专业的硬件设备,其部署配置和运维管理相对于交换机与路由器也较为复杂。如何利旧现有专用设备、降低改造费用成为园区网建设所需考虑的重要因素。本文通过引入SDN,阐述了如何基于SDN实现动态Service Chaining技术,实现按需引流。动态Service Chaining技术可实现网络出口智能引流、安全资源池化、网络安全协防,从而搭建一个富有弹性、高度可扩展的业务流处理平台。 展开更多
关键词 SDN service chaining 安全池化
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Dynamic Backup Sharing Scheme of Service Function Chains in NFV 被引量:2
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作者 Dong Zhang Zhifan Zheng +2 位作者 Xiang Lin Xiang Chen Chunming Wu 《China Communications》 SCIE CSCD 2022年第5期178-190,共13页
Service function chains(SFC)mapping takes the responsibility for managing virtual network functions(VNFs).In SFC mapping,existing solutions duplicate VNFs with redundant instances to provide high availability in respo... Service function chains(SFC)mapping takes the responsibility for managing virtual network functions(VNFs).In SFC mapping,existing solutions duplicate VNFs with redundant instances to provide high availability in response to failures.However,as a compromise,these solutions result in high resource consumption due to device maintenance.In this paper,we propose a novel method named dynamic backup sharing(DBS)that allows SFCs to dynamically share backups to reduce resource consumption.DBS formulates the problem of sharing backups among different VNFs as an integer linear programming(ILP).Thereafter,we design a novel online algorithm based on dynamic programming to solve the problem.The experimental results indicate that DBS outperforms state-ofthe-art works by reducing resource consumption and improving the number of accepted requests. 展开更多
关键词 network function virtualization service function chain mapping reliability backup sharing
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Multi-Path Service Function Chaining for Mobile Surveillance of Animal Husbandry
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作者 Xi Chen Tao Wu Mehtab Afzal 《Computers, Materials & Continua》 SCIE EI 2022年第4期1959-1971,共13页
Animal husbandry is the pillar industry in some ethnic areas of China.However,the communication/networking infrastructure in these areas is often underdeveloped,thus the difficulty in centralized management,and challe... Animal husbandry is the pillar industry in some ethnic areas of China.However,the communication/networking infrastructure in these areas is often underdeveloped,thus the difficulty in centralized management,and challenges for the effective monitoring.Considering the dynamics of the field monitoring environment,as well as the diversity and mobility of monitoring targets,traditional WSN(Wireless Sensor Networks)or IoT(Internet of Things)is difficult to meet the surveillance needs.Mobile surveillance that features the collaboration of various functions(camera,sensing,image recognition,etc.)deployed on mobile devices is desirable in a volatile wireless environment.This paper proposes the service function chaining for mobile surveillance of animal husbandry,which orchestrates multi-path multifunction(MPMF)chains to help mobile devices to collaborate in complex surveillance tasks,provide backup chains in case the primary service function chain fails due to mobility,signal strength,obstacle,etc.,and make up for the defects of difficult deployment of monitoring facilities in ethnic areas.MPMF algorithmmodels both mobile devices and various functions deployed on them as abstract graph nodes,so that chains that are required to traverse various functions and hosting mobile devices can be orchestrated in a single graphbased query through modified and adapted Dijkstra-like algorithms,with their cost ordered automatically.Experiment results show that the proposed MPMF algorithm finds multiple least-costly chains that traverse demanded functions in a timely fashion on Raspberry Pi-equipped mobile devices. 展开更多
关键词 service function chaining ORCHESTRATION SURVEILLANCE shortest path
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Research on Service Function Chain Orchestrating Algorithm Based on SDN and NFV
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作者 Yuning Jia Yu Gong Yifei Wei 《Journal of Quantum Computing》 2022年第1期39-52,共14页
Software defined network(SDN)and network function virtualization(NFV)have become a new paradigm of a new generation of network architecture.SDN and NFV can effectively improve the flexibility of deploying and managing... Software defined network(SDN)and network function virtualization(NFV)have become a new paradigm of a new generation of network architecture.SDN and NFV can effectively improve the flexibility of deploying and managing service function chains(SFCs).By combining SDN and NFV and applying them to the resource orchestration problem of SFC deployment,the three-tier architecture consisting of SDN controller,network function virtualization and physical underlying computing resource layer in the process of heterogeneous network resource mapping is considered.And an optimization algorithm for active control resources based on SDN and NFV is proposed.Firstly,the user’s utility is modeled by the multistandard aggregated multi-criteria utility algorithm,and the optimization goal is transformed into the problem of maximizing the user’s utility.Then the controller,based on the algorithm’s prediction of the future state and realtime monitoring of the network utilization,makes decisions and issues control commands for the arriving SFC requests,based on which it occupies the underlying resources held by the virtualized network function(VNF).The simulation results show that,compared with the static timing resource allocation algorithm,the active control resource deployment algorithm proposed in the article has better performance in terms of resource utilization,acceptance rate,and user creation utility. 展开更多
关键词 SDN NFV service function chain resource allocation
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Research of Order Allocation of E-commerce Logistics Service Supply Chain Considering Customer Evaluation
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作者 HU Yanyong 《International Journal of Plant Engineering and Management》 2020年第1期1-13,共13页
Based on the importance of customer evaluation for developing e-commerce enterprises,this paper analyzes the customer evaluation as a fuzzy variable and establishes a multi-objective mixed integer order allocation pla... Based on the importance of customer evaluation for developing e-commerce enterprises,this paper analyzes the customer evaluation as a fuzzy variable and establishes a multi-objective mixed integer order allocation planning model by considering customer satisfaction,which maximizes customer praise and minimizes procurement cost.As the optimization goal,transaction cost is optimized for the order allocation of the secondary e-commerce logistics service supply chain.In order to defuzzify the customer evaluation,a fuzzy evaluation method is designed to transform the customer evaluation from fuzzy language evaluation to numerical measurement.Finally,the feasibility and effectiveness of the model are verified by using a specific example,and the order is made for the e-commerce enterprise.The allocation provides a theoretical reference. 展开更多
关键词 customer reviews E-COMMERCE logistics service supply chain order allocation
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Virtualizing Network and Service Functions: Impact on ICT Transformation and Standardization 被引量:1
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作者 Bhumip Khasnabish Jie Hu Ghazanfar Ali 《ZTE Communications》 2013年第4期40-46,共7页
Virtualization of network/service functions means time sharing network/service(and affiliated)resources in a hyper speed manner.The concept of time sharing was popularized in the 1970s with mainframe computing.The s... Virtualization of network/service functions means time sharing network/service(and affiliated)resources in a hyper speed manner.The concept of time sharing was popularized in the 1970s with mainframe computing.The same concept has recently resurfaced under the guise of cloud computing and virtualized computing.Although cloud computing was originally used in IT for server virtualization,the ICT industry is taking a new look at virtualization.This paradigm shift is shaking up the computing,storage,networking,and ser vice industries.The hope is that virtualizing and automating configuration and service management/orchestration will save both capes and opex for network transformation.A complimentary trend is the separation(over an open interface)of control and transmission.This is commonly referred to as software defined networking(SDN).This paper reviews trends in network/service functions,efforts to standardize these functions,and required management and orchestration. 展开更多
关键词 network function virtualization(NFV) and chaining service function virtualization(SFV) and chaining network virtualization overlay(NVO) software defined networking(SDN) networking economics
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Game Theory Based Decision Coordination Strategy of Agricultural Logistics Service Information System
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作者 Long Guo Dongsheng Sun +1 位作者 Abdul Waheed Huijie Gao 《Computers, Materials & Continua》 SCIE EI 2022年第10期513-532,共20页
Under the background of“Internet plus”rapid development,the agricultural logistics industry should apply information technology to every link of the agricultural product logistics industry chain.By making full use o... Under the background of“Internet plus”rapid development,the agricultural logistics industry should apply information technology to every link of the agricultural product logistics industry chain.By making full use of the decision making module of the agricultural logistics information system,we can realize the full sharing of information and data resources,which makes the decision-making scheme of the agricultural logistics information system more optimized.In real economic society,the uncertainty and mismatch between the customer’s logistics service demand and the logistics service capability that the logistics service function provider can provide,that is,when the two information are asymmetric,how to use the third-party contract to coordinate the income and profit distribution of the two,to make the information system decision making more reasonable?This paper mainly studies the coordination scheme of agricultural logistics information system decision making under uncertain output and demand information by introducing the spot market.A joint coordination strategy based on revenue sharing and penalty feedback contracts proposes decentralized decision making based on game theory.Experiments show that the flexible ordering strategy proposed in this paper can reduce the logistics service supply chain’s uncertainty and significantly improve the logistics service supply chain’s overall income level through coordination contracts. 展开更多
关键词 Game theory decision coordination strategy agricultural logistics information system logistics service supply chain(LSSC)
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Impact of Quality and Government Subsidies on Elderly Care Services
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作者 Mengna Li Liyun Wu 《Proceedings of Business and Economic Studies》 2021年第4期139-145,共7页
In order to solve the problem of imbalance resource allocation and service income in the elderly care service industry,this article establishes three service income models in different situations for a single provider... In order to solve the problem of imbalance resource allocation and service income in the elderly care service industry,this article establishes three service income models in different situations for a single provider and a single integrator while considering the quality as well as government subsidies.The results showed that government subsidies can significantly improve quality efforts and service income with a mutual restriction between quality and service income.Government subsidies would have an impact on the quality,and they are more conducive to the service income of providers.When government subsidies are less than 80% of the service income,the incentive effect is better. 展开更多
关键词 Revenue model Pension service supply chain Quality preference Government subsidies
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SFC Design and VNF Placement Based on Traffic Volume Scaling and VNF Dependency in 5G Networks
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作者 Zhihao Zeng Zixiang Xia +1 位作者 Xiaoning Zhang Yexiao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1791-1814,共24页
The development of Fifth-Generation(5G)mobile communication technology has remarkably promoted the spread of the Internet of Things(IoT)applications.As a promising paradigm for IoT,edge computing can process the amoun... The development of Fifth-Generation(5G)mobile communication technology has remarkably promoted the spread of the Internet of Things(IoT)applications.As a promising paradigm for IoT,edge computing can process the amount of data generated by mobile intelligent devices in less time response.Network Function Virtualization(NFV)that decouples network functions from dedicated hardware is an important architecture to implement edge computing,deploying heterogeneous Virtual Network Functions(VNF)(such as computer vision,natural language processing,intelligent control,etc.)on the edge service nodes.With the NFV MANO(Management and Orchestration)framework,a Service Function Chain(SFC)that contains a set of ordered VNFs can be constructed and placed in the network to offer a customized network service.However,the procedure of NFV orchestration faces a technical challenge in minimizing the network cost of VNF placement due to the complexity of the changing effect of traffic volume and the dependency on theVNFrelationship.To this end,we jointly optimize SFC design and VNF placement to minimize resource cost while taking account of VNF dependency and traffic volume scaling.First,the problem is formulated as an Integer Linear Programming(ILP)model and proved NPhard by reduction from Hamiltonian Cycle problem.Then we proposed an efficient heuristic algorithm called Traffic Aware and Interdependent VNF Placement(TAIVP)to solve the problem.Compared with the benchmark algorithms,emulation results show that our algorithm can reduce network cost by 10.2%and increase service request acceptance rate by 7.6%on average. 展开更多
关键词 Network function virtualization virtual network function service function chain resource allocation routing
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Dynamic Security SFC Branching Path Selection Using Deep Reinforcement Learning
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作者 Shuangxing Deng Man Li Huachun Zhou 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期2919-2939,共21页
Security service function chaining(SFC)based on software-defined networking(SDN)and network function virtualization(NFV)technology allows traffic to be forwarded sequentially among different security service functions... Security service function chaining(SFC)based on software-defined networking(SDN)and network function virtualization(NFV)technology allows traffic to be forwarded sequentially among different security service functions to achieve a combination of security functions.Security SFC can be deployed according to requirements,but the current SFC is not flexible enough and lacks an effective feedback mechanism.The SFC is not traffic aware and the changes of traffic may cause the previously deployed security SFC to be invalid.How to establish a closed-loop mechanism to enhance the adaptive capability of the security SFC to malicious traffic has become an important issue.Our contribution is threefold.First,we propose a secure SFC path selection framework.The framework can accept the feedback results of traffic and security service functions in SFC,and dynamically select the opti-mal path for SFC based on the feedback results.It also realizes the automatic deployment of paths,forming a complete closed loop.Second,we expand the protocol of SFC to realize the security SFC with branching path,which improve flexibility of security SFC.Third,we propose a deep reinforcement learning-based dynamic path selection method for security SFC.It infers the optimal branching path by analyzing feedback from the security SFC.We have experimented with Distributed Denial of Service(DDoS)attack detection modules as security service functions.Experimental results show that our proposed method can dynamically select the optimal branching path for a security SFC based on traffic features and the state of the SFC.And it improves the accuracy of the overall malicious traffic detection of the security SFC and significantly reduces the latency and overall load of the SFC. 展开更多
关键词 service function chaining deep reinforcement learning security service
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Network Function Virtualization Technology:Progress and Standardization
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作者 Huiling Zhao Yunpeng Xie Fan Shi 《ZTE Communications》 2014年第2期3-7,共5页
Network innovation and business transformation are both necessary for telecom operators to adapt to new situations, but operators face challenges in terms of network bearer complexity, business centralization, and IT/... Network innovation and business transformation are both necessary for telecom operators to adapt to new situations, but operators face challenges in terms of network bearer complexity, business centralization, and IT/CT integration. Network function virtualization (NFV) may inspire new development ideas, but many doubts still exist within industry, especially about how to introduce NFV into an operator' s network. This article describes the latest progress in NFV standardization, NFV requirements and hot technology issues, and typical NFV applications in an operator networks. 展开更多
关键词 network functions virtualization (NFV) overlay network virtual extensible LAN (VXLAN) service chaining
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A Software-Defined Approach to IoT Networking 被引量:1
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作者 Christian Jacquenet Mohamed Boucadair 《ZTE Communications》 2016年第1期61-66,共6页
It is foreseen that the Internet of Things (IoT) will comprise billions of connected devices, and this will make the provi?sioning and operation of some IoT connectivity services more challenging. Indeed, IoT services... It is foreseen that the Internet of Things (IoT) will comprise billions of connected devices, and this will make the provi?sioning and operation of some IoT connectivity services more challenging. Indeed, IoT services are very different from lega?cy Internet services because of their dimensioning figures and also because IoT services differ dramatically in terms of na?ture and constraints. For example, IoT services often rely on energy and CPU?constrained sensor technologies, regardless of whether the service is for home automation, smart building, e?health, or power or water metering on a regional or national scale. Also, some IoT services, such as dynamic monitoring of biometric data, manipulation of sensitive information, and pri?vacy needs to be safeguarded whenever this information is for?warded over the underlying IoT network infrastructure. This paper discusses how software?defined networking (SDN) can facilitate the deployment and operation of some advanced IoT services regardless of their nature or scope. SDN introduces a high degree of automation in service delivery and operation-from dynamic IoT service parameter exposure and negotiation to resource allocation, service fulfillment, and assurance. This paper does not argue that all IoT services must adopt SDN. Rather, it is left to the discretion of operators to decide which IoT services can best leverage SDN capabilities. This paper only discusses managed IoT services, i.e., services that are op?erated by a service provider. 展开更多
关键词 AUTOMATION dynamic service provisioning Internet of Things service function chaining software-defined networking
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Optimize the Deployment and Integration for Multicast-Oriented Virtual Network Function Tree
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作者 Ying Chang Hongxue Yang Qinghua Zhu 《Journal of Beijing Institute of Technology》 EI CAS 2022年第5期513-523,共11页
Due to the development of network technology,the number of users is increasing rapidly,and the demand for emerging multicast services is becoming more and more abundant,traffic data is increasing day by day,network no... Due to the development of network technology,the number of users is increasing rapidly,and the demand for emerging multicast services is becoming more and more abundant,traffic data is increasing day by day,network nodes are becoming denser,network topology is becoming more complex,and operators’equipment operation and maintenance costs are increasing.Network functions virtualization multicast issues include building a traffic forwarding topology,deploying the required functions,and directing traffic.Combining the two is still a problem to be studied in depth at present,and this paper proposes a two-stage solution where the decisions of these two stages are interdependent.Specifically,this paper decouples multicast traffic forwarding and function delivery.The minimum spanning tree of traffic forwarding is constructed by Steiner tree,and the traffic forwarding is realized by Viterbi-algorithm.Use a general topology network to examine network cost and service performance.Simulation results show that this method can reduce overhead and delay and optimize user experience. 展开更多
关键词 MULTICAST service function chain(SFC) network functions virtualization(NFV) software defined network(SDN) Viterbi-algorithm
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NfvInsight:A Framework for Automatically Deploying and Benchmarking VNF Chains
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作者 徐天妮 孙海锋 +5 位作者 张笛 周小明 隋秀峰 王卅 黄群 包云岗 《Journal of Computer Science & Technology》 SCIE EI CSCD 2022年第3期680-698,共19页
With the advent of virtualization techniques and software-defined networking(SDN),network function virtualization(NFV)shifts network functions(NFs)from hardware implementations to software appliances,between which exi... With the advent of virtualization techniques and software-defined networking(SDN),network function virtualization(NFV)shifts network functions(NFs)from hardware implementations to software appliances,between which exists a performance gap.How to narrow the gap is an essential issue of current NFV research.However,the cumbersomeness of deployment,the water pipe effect of virtual network function(VNF)chains,and the complexity of the system software stack together make it tough to figure out the cause of low performance in the NFV system.To pinpoint the NFV system performance,we propose NfvInsight,a framework for automatic deployment and benchmarking VNF chains.Our framework tackles the challenges in NFV performance analysis.The framework components include chain graph generation,automatic deployment,and fine granularity measurement.The design and implementation of each component have their advantages.To the best of our knowledge,we make the first attempt to collect rules forming a knowledge base for generating reasonable chain graphs.NfvInsight deploys the generated chain graphs automatically,which frees the network operators from executing at least 391 lines of bash commands for a single test.To diagnose the performance bottleneck,NfvInsight collects metrics from multiple layers of the software stack.Specifically,we collect the network stack latency distribution ingeniously,introducing only less than 2.2%overhead.We showcase the convenience and usability of NfvInsight in finding bottlenecks for both VNF chains and the underlying system.Leveraging our framework,we find several design flaws of the network stack,which are unsuitable for packet forwarding inside one single server under the NFV circumstance.Our optimization for these flaws gains at most 3x performance improvement. 展开更多
关键词 network function virtualization(NFV) service chain performance bottleneck network stack latency
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Studyt on the Emergency Medical Service Evaluation and Improvement
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作者 WU Hai-long SU Qiang +1 位作者 ZHU Yan XUE Lei 《International Journal of Plant Engineering and Management》 2014年第4期199-206,共8页
The Emergency Medical Service( EMS) system in China from service supply chain perspective is analyzed. Firstly,it reviews service supply chain researches in emergency medical service,and it is found that waiting tim... The Emergency Medical Service( EMS) system in China from service supply chain perspective is analyzed. Firstly,it reviews service supply chain researches in emergency medical service,and it is found that waiting time,safety,service integration and communication before the emergency surgery are the four indicators to measure the quality of emergency medical service. Secondly,the information barrier-inconsistent information flow-is prominent,which is between emergency in hospital and pre-hospital,after analyzing three different types of flows on service, information and logistics. Besides, comparing with Joint Commission International accreditation( JCI) standards for hospitals in USA,the requirements of service integration and communication in Chinese hospital accreditation are much lower. In the end,a Smart First Aid Information Center( SFAIC) model for first aid service is proposed. This model can be used to enhance information exchanges more effectively between first aid in-and pre-hospital. Moreover,it also shortens pre-surgery time and betters the communication and coordination between service sections. To put it in a nutshell,the improved medical service process can greatly increase emergency medical service quality. 展开更多
关键词 Emergency Medical service(EMS) service supply chain service quality smart first aid information center(SFAIC)
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