The controller is indispensable in software-defined networking(SDN).With several features,controllers monitor the network and respond promptly to dynamic changes.Their performance affects the quality-of-service(QoS)in...The controller is indispensable in software-defined networking(SDN).With several features,controllers monitor the network and respond promptly to dynamic changes.Their performance affects the quality-of-service(QoS)in SDN.Every controller supports a set of features.However,the support of the features may be more prominent in one controller.Moreover,a single controller leads to performance,single-point-of-failure(SPOF),and scalability problems.To overcome this,a controller with an optimum feature set must be available for SDN.Furthermore,a cluster of optimum feature set controllers will overcome an SPOF and improve the QoS in SDN.Herein,leveraging an analytical network process(ANP),we rank SDN controllers regarding their supporting features and create a hierarchical control plane based cluster(HCPC)of the highly ranked controller computed using the ANP,evaluating their performance for the OS3E topology.The results demonstrated in Mininet reveal that a HCPC environment with an optimum controller achieves an improved QoS.Moreover,the experimental results validated in Mininet show that our proposed approach surpasses the existing distributed controller clustering(DCC)schemes in terms of several performance metrics i.e.,delay,jitter,throughput,load balancing,scalability and CPU(central processing unit)utilization.展开更多
In order to effectively control the deformation and failure of surrounding rocks in a coal roadway in a deep tectonic region, the deformation and failure mechanism and stability control mechanism were studied. With su...In order to effectively control the deformation and failure of surrounding rocks in a coal roadway in a deep tectonic region, the deformation and failure mechanism and stability control mechanism were studied. With such methods as numerical simulation and field testing, the distribution law of the displacement, stress and plastic zone in the surrounding rocks was analyzed. The deformation and failure mechanisms of coal roadways in deep tectonic areas were revealed: under high tectonic stress, two sides will slide along the roof or floor; while the plastic zone of the two sides will extend along the roof or floor,leading to more serious deformation and failure in the corner of two sides and the bolt supporting the corners is readily cut off by the shear force or tension force. Aimed at controlling the large slippage deformation of the two sides, serious deformation and failure in the corners of the two sides and massive bolt breakage, a ‘‘controlling and yielding coupling support'' control technology is proposed. Firstly, bolts which do not pass through the bedding plane should be used in the corners of the roadway, allowing the two sides to have some degree of sliding to achieve the purpose of ‘‘yielding'' support, and which avoid breakage of the bolts in the corner. After yielding support, bolts in the corner of the roadway and which pass through the bedding plane should be used to control the deformation and failure of the coal in the corner. ‘‘Controlling and yielding coupling support'' technology has been successfully applied in engineering practice, and the stability of deep coal roadway has been greatly improved.展开更多
For the next generation optical switching networks, the intelligent control plane is a key enabling technique. In this paper, we review our recent research activities related to Generalized Multi-Protocol Label Switch...For the next generation optical switching networks, the intelligent control plane is a key enabling technique. In this paper, we review our recent research activities related to Generalized Multi-Protocol Label Switching (GMPLS) and Open Flow-based control planes for both Wave length Switched Optical Networks (WSON) and Elastic Optical Networks (EON).展开更多
Software-Defined Networking(SDN)provides flexible and global network management by decoupling control plane from data plane,and multiple controllers are deployed in the network in a logically centralized and physicall...Software-Defined Networking(SDN)provides flexible and global network management by decoupling control plane from data plane,and multiple controllers are deployed in the network in a logically centralized and physically distributed way.However,the existing approaches generally deploy the controllers with the same type in the network,which easily causes homogeneous controller common-mode fault.To this end,this paper proposes heterogeneous controller deployment in the SDN,considering the different types of controllers and relevant criteria(e.g.,delay,control link interruption rate,and controller fault rate).Then,we introduce a Safe and Reliable Heterogeneous Controller Deployment(SRHCD)approach,consisting of two stages.Stage 1 determines the type and the number of heterogeneous controllers required for the SDN network based on the dynamic programming.Stage 2 divides the SDN network into multiple subnets by k-means algorithm and improves the genetic algorithm to optimize the heterogeneous controller deployment in these SDN subnets to ensure reliable switch-controller communications.Finally,the simulation results show that the proposed approach can effectively reduce the control plane fault rate and increase the attack difficulties.Besides,the switch-controller delay has been lowered by 16.5%averagely.展开更多
When applying Software-Defined Networks(SDN) to WANs,the SDN flexibility enables the cross-domain control to achieve a better control scalability.However,the control consistence is required by all the cross-domain ser...When applying Software-Defined Networks(SDN) to WANs,the SDN flexibility enables the cross-domain control to achieve a better control scalability.However,the control consistence is required by all the cross-domain services,to ensure the data plane configured in consensus for different domains.Such consistence process is complicated by potential failure and errors of WANs.In this paper,we propose a consistence layer to actively and passively snapshot the cross-domain control states,to reduce the complexities of service realizations.We implement the layer and evaluate performance in the PlanetLab testbed for the WAN emulation.The testbed conditions are extremely enlarged comparing to the real network.The results show its scalability,reliability and responsiveness in dealing with the control dynamics.In the normalized results,the active and passive snapshots are executed with the mean times of 1.873 s and 105 ms in135 controllers,indicating its readiness to be used in the real network.展开更多
The plane form of a gully can provide a basis for evaluating the gully volume and erosion rate, acting process, and evolutionary stage. For describing the planar characteristics of a permanent gully and understanding ...The plane form of a gully can provide a basis for evaluating the gully volume and erosion rate, acting process, and evolutionary stage. For describing the planar characteristics of a permanent gully and understanding their controlling factors, this study, utilizing a total station and GPS RTK, measured the shoulder lines and channel curves of 112 gullies in six sites of the Yuanmou Dry-hot Valley and then mapped them by Arc GIS software and calculated nine parameters. The results showed that the channel lengths range from 10.88 to 249.11 m; the widths range from 6.20 to 40.99 m; the perimeters range from 54.11 to 541.67 m; the gully areas range from 153.02 to 6,930.30 m2; the left-side areas range from 92.93 to 4,027.20 m2; and the right-side areas range from 63.65 to 3,539.77 m2. The slightly sinuous and straight gullies account for 73.21% of the total gullies; the quantity of the right skewed gullies is 8.93% greater than that of the left skewed ones based on the symmetry ratio; the shape ratios range from 1.12 to 1.40 and the morphology ratios from 0.038 to 1.294; the fractal dimension is 1.192. Gullies in different sites have diverse planar characteristics. Except for the symmetry index, which was close to a negatively skewed distribution, all of the other parameters had the characteristic of positively skewed distribution. The gully area is related to the length and width, but the gully length has a weak correlation with the width. The evolutionary stage, topographic conditions, strata, soil properties, and piping erosion played very important roles in the gully planar morphology. This study could provide useful information for controlling gully erosion and safeguarding human habitation and engineering buildings.展开更多
The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features ...The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features such as rapid provisioning,automated protection and restoration(P&R),efficient resource allocation,and support for different quality of service(QoS) requirements.In this paper,we propose a novel stateful PCE-cloud(SPC)based architecture of GMPLS optical networks for cloud services.The cloud computing technologies(e.g.virtualization and parallel computing) are applied to the construction of SPC for improving the reliability and maximizing resource utilization.The functions of SPC and GMPLS based control plane are expanded according to the features of cloud services for different QoS requirements.The architecture and detailed description of the components of SPC are provided.Different potential cooperation relationships between public stateful PCE cloud(PSPC) and region stateful PCE cloud(RSPC) are investigated.Moreover,we present the policy-enabled and constraint-based routing scheme base on the cooperation of PSPC and RSPC.Simulation results for verifying the performance of routing and control plane reliability are analyzed.展开更多
Blasting operation dissipates much of the blasting energy in crushing the rock at the borehole and the resulting cracks are randomly oriented. There is very little control of the fracture plane. In order to control th...Blasting operation dissipates much of the blasting energy in crushing the rock at the borehole and the resulting cracks are randomly oriented. There is very little control of the fracture plane. In order to control the fracture plane, many methods have been applied. This paper discusses a new blasting method in which a high degree of fracture control can be achieved while minimizing the ground shock.展开更多
G2MPLS is a Network Control Plane(NCP) architecture that implements the concept of Grid Network Services(GNS) required for implementing photonic Grids.It provides part of the functionalities related to the selection,c...G2MPLS is a Network Control Plane(NCP) architecture that implements the concept of Grid Network Services(GNS) required for implementing photonic Grids.It provides part of the functionalities related to the selection,co-allocation and maintenance of both Grid and network resources through a set of seamless procedures at the user-to-network and inter-domain boundaries.G2MPLS' main features and procedures are presented in this document,as well as the considerations to deploy it and facilitate its dissemination.展开更多
The information centric network(ICN)has been widely discussed in current researches.The ICN interoperation with a traditional IP network and caching methods are one of the research topics of interest.For economic reas...The information centric network(ICN)has been widely discussed in current researches.The ICN interoperation with a traditional IP network and caching methods are one of the research topics of interest.For economic reasons,the capability of applying the ICN to internet service providers(ISPs)with various traditional IP protocols already implemented,especially IGP,MPLS,VRF,and TE,does not require any change on the IP network infrastructure.The biggest concern of ISPs is related to their customers’contents delivery speed.In this paper,we consider ICN caching locations in ISP by using the concept of locator/ID separation protocol(LISP)for interoperation between a traditional IP address and name-based ICN.To be more specific,we propose a new procedure to determine caching locations in the ICN by using the cuckoo search algorithm(CSA)for finding the best caching locations of information chunks.Moreover,we create the smart control plane(SCP)scheme which is an intelligent controlling,managing,and mapping system.Its function is similar to the software defined network concept.We show how the proposed SCP system works in both synthetic small network and real-world big network.Finally,we show and evaluate the performance of our algorithm comparison with the simple search method using the shortest path first algorithm.展开更多
The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load ...The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load of the core network when there is a macro base station(BS) failure in the control plane, a scheme of transferring the control of small cells under the coverage of the failure macro BS to the neighbor macro BSs is proposed. The average handover rates between small cells related to user mobilities, the extended coverage of the neighboring macro BSs under the constraint of transmitting power and the load balance index of the system are analyzed, based on which the formula of maximizing the handovers processed by macro BSs is constructed and further solved by the convex optimization methods. Simulation results indicate that the proposed scheme can effectively increase the total handovers processed by the macro BSs and thus reduce the signaling load of the core network.展开更多
The Internet of Things(IoT)has been widely adopted in various domains including smart cities,healthcare,smart factories,etc.In the last few years,the fitness industry has been reshaped by the introduction of smart fit...The Internet of Things(IoT)has been widely adopted in various domains including smart cities,healthcare,smart factories,etc.In the last few years,the fitness industry has been reshaped by the introduction of smart fitness solutions for individuals as well as fitness gyms.The IoT fitness devices collect trainee data that is being used for various decision-making.However,it will face numerous security and privacy issues towards its realization.This work focuses on IoT security,especially DoS/DDoS attacks.In this paper,we have proposed a novel blockchain-enabled protocol(BEP)that uses the notion of a self-exposing node(SEN)approach for securing fitness IoT applications.The blockchain and SDN architectures are employed to enhance IoT security by a highly preventive security monitoring,analysis and response system.The proposed approach helps in detecting the DoS/DDoS attacks on the IoT fitness system and then mitigating the attacks.The BEP is used for handling Blockchain-related activities and SEN could be a sensor or actuator node within the fitness IoT system.SEN provides information about the inbound and outbound traffic to the BEP which is used to analyze the DoS/DDoS attacks on the fitness IoT system.The SENcalculates the inbound and outbound traffic features’entropies and transmits them to the Blockchain in the form of transaction blocks.The BEP picks the whole mined blocks’transactions and transfers them to the SDN controller node.The controller node correlates the entropies data of SENs and decides about the DoS or DDoS attack.So,there are two decision points,one is SEN,and another is the controller.To evaluate the performance of our proposed system,several experiments are performed and results concerning the entropy values and attack detection rate are obtained.The proposed approach has outperformed the other two approaches concerning the attack detection rate by an increase of 11%and 18%against Approach 1 and Approach 2 respectively.展开更多
The key technologies involved in the evolution of the Cloud-based Radio Access Network(C-RAN) are discussed in this paper. Taking the Frameless Network Architecture(FNA) as a starting point, a cell-lessbased network t...The key technologies involved in the evolution of the Cloud-based Radio Access Network(C-RAN) are discussed in this paper. Taking the Frameless Network Architecture(FNA) as a starting point, a cell-lessbased network topology for a multi-tier Heterogeneous Network(Het Net) and ultra-dense network is proposed. The FNA network topology modeling is researched with centralized processing and distributed antenna deployments. The Antenna Element(AE) is released as a new dimensional radio resource that is included in the centralized Radio Resource Management(RRM) processes. This contributes to the on-demand user-centric serving-set associations with cell-edge effect elimination. The Control Plane(CP) and User Plane(UP) separation and adaptation are introduced for energy efficiency improvements. The centralized RRM and different optimization goals are discussed for fully exploring the merits from the centralized computing of C-RAN. Considering the complexity, near-optimal approaches for specific users' Quality-of-Service(Qo S) requirements are addressed. Finally, based on the research highlighted above, the way forward of C-RAN evolution is discussed.展开更多
The concept of Software-Defined Networking(SDN)evolves to overcome the drawbacks of the traditional networks with Internet Protocol(I.P.)packets sending and packets handling.The SDN structure is one of the critical ad...The concept of Software-Defined Networking(SDN)evolves to overcome the drawbacks of the traditional networks with Internet Protocol(I.P.)packets sending and packets handling.The SDN structure is one of the critical advantages of efficiently separating the data plane from the control plane tomanage the network configurations and network management.Whenever there aremultiple sending devices inside the SDNnetwork,theOpenFlow switches are programmed to handle the limited number of requests for their interface.When the recommendations are exceeded from the specific threshold,the load on the switches also increases.This research article introduces a new approach named LBoBS to handle load balancing by adding the load balancing server to the SDN network.Besides,it is used to maximize SDN’s reliability and efficiency.It also works in coordination with the controller to effectively handle the load balancing policies.The load balancing server is implemented to manage the switches load effectively.Results are evaluated on the NS-3 simulator for packet delivery,bandwidth utilization,latency control,and packet decision ratios on the OpenFlow switches.It has been found that the proposed method improved SDN’s load balancing by 70%compared to the previous state-of-the-art methods.展开更多
With the expansion of network services,large-scale networks have progressively become common.The network status changes rapidly in response to customer needs and configuration changes,so network configuration changes ...With the expansion of network services,large-scale networks have progressively become common.The network status changes rapidly in response to customer needs and configuration changes,so network configuration changes are also very frequent.However,no matter what changes,the network must ensure the correct conditions,such as isolating tenants from each other or guaranteeing essential services.Once changes occur,it is necessary to verify the after-changed network.Whereas,for the verification of large-scale network configuration changes,many current verifiers show poor efficiency.In order to solve the problem ofmultiple global verifications caused by frequent updates of local configurations in large networks,we present a fast configuration updates verification tool,FastCUV,for distributed control planes.FastCUV aims to enhance the efficiency of distributed control plane verification for medium and large networks while ensuring correctness.This paper presents a method to determine the network range affected by the configuration change.We present a flow model and graph structure to facilitate the design of verification algorithms and speed up verification.Our scheme verifies the network area affected by obtaining the change of the Forwarding Information Base(FIB)before and after.FastCUV supports rich network attributes,meanwhile,has high efficiency and correctness performance.After experimental verification and result analysis,our method outperforms the state-of-the-art method to a certain extent.展开更多
Software defined networking(SDN)has attracted significant attention from both academia and industry by its ability to reconfigure network devices with logically centralized applications.However,some critical security ...Software defined networking(SDN)has attracted significant attention from both academia and industry by its ability to reconfigure network devices with logically centralized applications.However,some critical security issues have also been introduced along with the benefits,which put an obstruction to the deployment of SDN.One root cause of these issues lies in the limited resources and capability of devices involved in the SDN architecture,especially the hardware switches lied in the data plane.In this paper,we analyze the vulnerability of SDN and present two kinds of SDN-targeted attacks:1)data-to-control plane saturation attack which exhausts resources of all SDN components,including control plane,data plane,and the in-between downlink channel and 2)control plane reflection attack which only attacks the data plane and gets conducted in a more efficient and hidden way.Finally,we propose the corresponding defense frameworks to mitigate such attacks.展开更多
Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation posit...Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation positioning and science exploration. In this paper, the architecture of Software Defined Space Optical Network (SDSON) based on cloud platform is designed by means of Software Defined Optical Network (SDON) and cloud services. The new architecture combining centralized and distributed management-control mechanism is a multi-layer and multi-domain architecture with powerful computing and storage ability. Moreover, reliable service and unreliable service communication models employed in the space information network are proposed considering the characteristic of Disruption/Delay Tolerant Network (DTN). Finally, the functional verification and demonstration are performed on our optical experimental network platform.展开更多
Automatic Switched Optical network (ASON) is the key technology for the next generation optical networks, and the recommendations for ASON were also developed by ITU-T. However, the recommendations for the management ...Automatic Switched Optical network (ASON) is the key technology for the next generation optical networks, and the recommendations for ASON were also developed by ITU-T. However, the recommendations for the management plane have not been made yet. In this paper, the management information model for the resources of control plane is proposed based on the management requirements of ASON for the first time. The managed objects for control plane could be used for the management of control Network Elements(NEs) and control channels, they can also be used for route areas division in control plane, parameter configuration and performance inspection for the control modules in a control NEs.展开更多
This article discusses the issue of resource conflict in the generalized multi-protocol label switching (GMPLS) controlled optical network. Based on the analysis of the current random rebuilding mechanism and its dr...This article discusses the issue of resource conflict in the generalized multi-protocol label switching (GMPLS) controlled optical network. Based on the analysis of the current random rebuilding mechanism and its drawbacks, this article presents two enhanced solutions for improvement, namely, the priority-based resource allocation mechanism and the network management system (NMS) based sequential resource allocation mechanism. Experimental results show that the presented mechanisms perform better than the original random rebuilding solution in terms of the connection setup/recovery time and successful rate.展开更多
The convergence of data and optical networks is a charming tendency of the current network evolution. In this paper, we propose a novel data and optical network integrating device. Based on it, a converging network st...The convergence of data and optical networks is a charming tendency of the current network evolution. In this paper, we propose a novel data and optical network integrating device. Based on it, a converging network structure is put forward and named Hierarchical Data and Optical Networking Integrating (HDONI) networking architecture.展开更多
基金supported by the MSIT(Ministry of Science and ICT),Korea,under the ITRC(Information Technology Research Center)support program(IITP-2020-2018-0-01431)supervised by the IITP(Institute for Information&Communications Technology Planning&Evaluation).
文摘The controller is indispensable in software-defined networking(SDN).With several features,controllers monitor the network and respond promptly to dynamic changes.Their performance affects the quality-of-service(QoS)in SDN.Every controller supports a set of features.However,the support of the features may be more prominent in one controller.Moreover,a single controller leads to performance,single-point-of-failure(SPOF),and scalability problems.To overcome this,a controller with an optimum feature set must be available for SDN.Furthermore,a cluster of optimum feature set controllers will overcome an SPOF and improve the QoS in SDN.Herein,leveraging an analytical network process(ANP),we rank SDN controllers regarding their supporting features and create a hierarchical control plane based cluster(HCPC)of the highly ranked controller computed using the ANP,evaluating their performance for the OS3E topology.The results demonstrated in Mininet reveal that a HCPC environment with an optimum controller achieves an improved QoS.Moreover,the experimental results validated in Mininet show that our proposed approach surpasses the existing distributed controller clustering(DCC)schemes in terms of several performance metrics i.e.,delay,jitter,throughput,load balancing,scalability and CPU(central processing unit)utilization.
基金Financial support for this work, provided by the National Natural Science Foundation of China (No. 51204166)the Henan Polytechnic University Doctor Foundation (No. B2012-081)
文摘In order to effectively control the deformation and failure of surrounding rocks in a coal roadway in a deep tectonic region, the deformation and failure mechanism and stability control mechanism were studied. With such methods as numerical simulation and field testing, the distribution law of the displacement, stress and plastic zone in the surrounding rocks was analyzed. The deformation and failure mechanisms of coal roadways in deep tectonic areas were revealed: under high tectonic stress, two sides will slide along the roof or floor; while the plastic zone of the two sides will extend along the roof or floor,leading to more serious deformation and failure in the corner of two sides and the bolt supporting the corners is readily cut off by the shear force or tension force. Aimed at controlling the large slippage deformation of the two sides, serious deformation and failure in the corners of the two sides and massive bolt breakage, a ‘‘controlling and yielding coupling support'' control technology is proposed. Firstly, bolts which do not pass through the bedding plane should be used in the corners of the roadway, allowing the two sides to have some degree of sliding to achieve the purpose of ‘‘yielding'' support, and which avoid breakage of the bolts in the corner. After yielding support, bolts in the corner of the roadway and which pass through the bedding plane should be used to control the deformation and failure of the coal in the corner. ‘‘Controlling and yielding coupling support'' technology has been successfully applied in engineering practice, and the stability of deep coal roadway has been greatly improved.
文摘For the next generation optical switching networks, the intelligent control plane is a key enabling technique. In this paper, we review our recent research activities related to Generalized Multi-Protocol Label Switching (GMPLS) and Open Flow-based control planes for both Wave length Switched Optical Networks (WSON) and Elastic Optical Networks (EON).
基金National Key Research and Development Project of China(No.2020YFB1804803)National Natural Science Foundation of China(No.61802429,61872382).
文摘Software-Defined Networking(SDN)provides flexible and global network management by decoupling control plane from data plane,and multiple controllers are deployed in the network in a logically centralized and physically distributed way.However,the existing approaches generally deploy the controllers with the same type in the network,which easily causes homogeneous controller common-mode fault.To this end,this paper proposes heterogeneous controller deployment in the SDN,considering the different types of controllers and relevant criteria(e.g.,delay,control link interruption rate,and controller fault rate).Then,we introduce a Safe and Reliable Heterogeneous Controller Deployment(SRHCD)approach,consisting of two stages.Stage 1 determines the type and the number of heterogeneous controllers required for the SDN network based on the dynamic programming.Stage 2 divides the SDN network into multiple subnets by k-means algorithm and improves the genetic algorithm to optimize the heterogeneous controller deployment in these SDN subnets to ensure reliable switch-controller communications.Finally,the simulation results show that the proposed approach can effectively reduce the control plane fault rate and increase the attack difficulties.Besides,the switch-controller delay has been lowered by 16.5%averagely.
基金supported by the National Basic Research Program of China (2012CB315903)the Program for Key Science and Technology Innovation Team of Zhejiang Province(2011R50010,2013TD20)+3 种基金the National High Technology Research Program of China(2015AA016103)the National Natural Science Foundation of China(61379118)the Research Fund of ZTE CorporationJiaxing Science and Technology Project (No.2014AY21021)
文摘When applying Software-Defined Networks(SDN) to WANs,the SDN flexibility enables the cross-domain control to achieve a better control scalability.However,the control consistence is required by all the cross-domain services,to ensure the data plane configured in consensus for different domains.Such consistence process is complicated by potential failure and errors of WANs.In this paper,we propose a consistence layer to actively and passively snapshot the cross-domain control states,to reduce the complexities of service realizations.We implement the layer and evaluate performance in the PlanetLab testbed for the WAN emulation.The testbed conditions are extremely enlarged comparing to the real network.The results show its scalability,reliability and responsiveness in dealing with the control dynamics.In the normalized results,the active and passive snapshots are executed with the mean times of 1.873 s and 105 ms in135 controllers,indicating its readiness to be used in the real network.
基金funded by the National Natural Science Foundation of China (41101348)
文摘The plane form of a gully can provide a basis for evaluating the gully volume and erosion rate, acting process, and evolutionary stage. For describing the planar characteristics of a permanent gully and understanding their controlling factors, this study, utilizing a total station and GPS RTK, measured the shoulder lines and channel curves of 112 gullies in six sites of the Yuanmou Dry-hot Valley and then mapped them by Arc GIS software and calculated nine parameters. The results showed that the channel lengths range from 10.88 to 249.11 m; the widths range from 6.20 to 40.99 m; the perimeters range from 54.11 to 541.67 m; the gully areas range from 153.02 to 6,930.30 m2; the left-side areas range from 92.93 to 4,027.20 m2; and the right-side areas range from 63.65 to 3,539.77 m2. The slightly sinuous and straight gullies account for 73.21% of the total gullies; the quantity of the right skewed gullies is 8.93% greater than that of the left skewed ones based on the symmetry ratio; the shape ratios range from 1.12 to 1.40 and the morphology ratios from 0.038 to 1.294; the fractal dimension is 1.192. Gullies in different sites have diverse planar characteristics. Except for the symmetry index, which was close to a negatively skewed distribution, all of the other parameters had the characteristic of positively skewed distribution. The gully area is related to the length and width, but the gully length has a weak correlation with the width. The evolutionary stage, topographic conditions, strata, soil properties, and piping erosion played very important roles in the gully planar morphology. This study could provide useful information for controlling gully erosion and safeguarding human habitation and engineering buildings.
基金supported by National Natural Science Foundation of China(No.61571061)Innovative Research Fund of Beijing University of Posts and Telecommunications (2015RC16)
文摘The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features such as rapid provisioning,automated protection and restoration(P&R),efficient resource allocation,and support for different quality of service(QoS) requirements.In this paper,we propose a novel stateful PCE-cloud(SPC)based architecture of GMPLS optical networks for cloud services.The cloud computing technologies(e.g.virtualization and parallel computing) are applied to the construction of SPC for improving the reliability and maximizing resource utilization.The functions of SPC and GMPLS based control plane are expanded according to the features of cloud services for different QoS requirements.The architecture and detailed description of the components of SPC are provided.Different potential cooperation relationships between public stateful PCE cloud(PSPC) and region stateful PCE cloud(RSPC) are investigated.Moreover,we present the policy-enabled and constraint-based routing scheme base on the cooperation of PSPC and RSPC.Simulation results for verifying the performance of routing and control plane reliability are analyzed.
文摘Blasting operation dissipates much of the blasting energy in crushing the rock at the borehole and the resulting cracks are randomly oriented. There is very little control of the fracture plane. In order to control the fracture plane, many methods have been applied. This paper discusses a new blasting method in which a high degree of fracture control can be achieved while minimizing the ground shock.
文摘G2MPLS is a Network Control Plane(NCP) architecture that implements the concept of Grid Network Services(GNS) required for implementing photonic Grids.It provides part of the functionalities related to the selection,co-allocation and maintenance of both Grid and network resources through a set of seamless procedures at the user-to-network and inter-domain boundaries.G2MPLS' main features and procedures are presented in this document,as well as the considerations to deploy it and facilitate its dissemination.
文摘The information centric network(ICN)has been widely discussed in current researches.The ICN interoperation with a traditional IP network and caching methods are one of the research topics of interest.For economic reasons,the capability of applying the ICN to internet service providers(ISPs)with various traditional IP protocols already implemented,especially IGP,MPLS,VRF,and TE,does not require any change on the IP network infrastructure.The biggest concern of ISPs is related to their customers’contents delivery speed.In this paper,we consider ICN caching locations in ISP by using the concept of locator/ID separation protocol(LISP)for interoperation between a traditional IP address and name-based ICN.To be more specific,we propose a new procedure to determine caching locations in the ICN by using the cuckoo search algorithm(CSA)for finding the best caching locations of information chunks.Moreover,we create the smart control plane(SCP)scheme which is an intelligent controlling,managing,and mapping system.Its function is similar to the software defined network concept.We show how the proposed SCP system works in both synthetic small network and real-world big network.Finally,we show and evaluate the performance of our algorithm comparison with the simple search method using the shortest path first algorithm.
基金Supported by Basic Research Program of BJUT(No.040000546317525)National Natural Science Foundation of China(No.61571021)+1 种基金Foundation of Beijing Municipal Commission of Education(No.KM201610005004,KM201510005006)Beijing Postdoctoral Research Foundation(No.2018ZZ029)
文摘The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load of the core network when there is a macro base station(BS) failure in the control plane, a scheme of transferring the control of small cells under the coverage of the failure macro BS to the neighbor macro BSs is proposed. The average handover rates between small cells related to user mobilities, the extended coverage of the neighboring macro BSs under the constraint of transmitting power and the load balance index of the system are analyzed, based on which the formula of maximizing the handovers processed by macro BSs is constructed and further solved by the convex optimization methods. Simulation results indicate that the proposed scheme can effectively increase the total handovers processed by the macro BSs and thus reduce the signaling load of the core network.
基金This research was supported by Energy Cloud R&D Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT(2019M3F2A1073387)and this research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2018R1D1A1A09082919)and this research was supported by Institute for Information&communications Technology Planning&Evaluation(IITP)grant funded by the Korea government(MSIT)(No.2018-0-01456,AutoMaTa:Autonomous Management framework based on artificial intelligent Technology for adaptive and disposable IoT).Any correspondence related to this paper should be addressed to Do-hyeun Kim.
文摘The Internet of Things(IoT)has been widely adopted in various domains including smart cities,healthcare,smart factories,etc.In the last few years,the fitness industry has been reshaped by the introduction of smart fitness solutions for individuals as well as fitness gyms.The IoT fitness devices collect trainee data that is being used for various decision-making.However,it will face numerous security and privacy issues towards its realization.This work focuses on IoT security,especially DoS/DDoS attacks.In this paper,we have proposed a novel blockchain-enabled protocol(BEP)that uses the notion of a self-exposing node(SEN)approach for securing fitness IoT applications.The blockchain and SDN architectures are employed to enhance IoT security by a highly preventive security monitoring,analysis and response system.The proposed approach helps in detecting the DoS/DDoS attacks on the IoT fitness system and then mitigating the attacks.The BEP is used for handling Blockchain-related activities and SEN could be a sensor or actuator node within the fitness IoT system.SEN provides information about the inbound and outbound traffic to the BEP which is used to analyze the DoS/DDoS attacks on the fitness IoT system.The SENcalculates the inbound and outbound traffic features’entropies and transmits them to the Blockchain in the form of transaction blocks.The BEP picks the whole mined blocks’transactions and transfers them to the SDN controller node.The controller node correlates the entropies data of SENs and decides about the DoS or DDoS attack.So,there are two decision points,one is SEN,and another is the controller.To evaluate the performance of our proposed system,several experiments are performed and results concerning the entropy values and attack detection rate are obtained.The proposed approach has outperformed the other two approaches concerning the attack detection rate by an increase of 11%and 18%against Approach 1 and Approach 2 respectively.
基金supported by the National High Technology Research and Development Program of China No.2014AA01A701Nature and Science Foundation of China under Grants No.61471068,61421061+2 种基金Beijing Nova Programme No.Z131101000413030International Collaboration Project No.2015DFT10160National Major Project No.2016ZX03001009-003
文摘The key technologies involved in the evolution of the Cloud-based Radio Access Network(C-RAN) are discussed in this paper. Taking the Frameless Network Architecture(FNA) as a starting point, a cell-lessbased network topology for a multi-tier Heterogeneous Network(Het Net) and ultra-dense network is proposed. The FNA network topology modeling is researched with centralized processing and distributed antenna deployments. The Antenna Element(AE) is released as a new dimensional radio resource that is included in the centralized Radio Resource Management(RRM) processes. This contributes to the on-demand user-centric serving-set associations with cell-edge effect elimination. The Control Plane(CP) and User Plane(UP) separation and adaptation are introduced for energy efficiency improvements. The centralized RRM and different optimization goals are discussed for fully exploring the merits from the centralized computing of C-RAN. Considering the complexity, near-optimal approaches for specific users' Quality-of-Service(Qo S) requirements are addressed. Finally, based on the research highlighted above, the way forward of C-RAN evolution is discussed.
基金This research was supported by a Grant(21RERP-B090228-08)from Residential Environment Research Program funded by Ministry of Land,Infrastructure and Transport of Korean government.
文摘The concept of Software-Defined Networking(SDN)evolves to overcome the drawbacks of the traditional networks with Internet Protocol(I.P.)packets sending and packets handling.The SDN structure is one of the critical advantages of efficiently separating the data plane from the control plane tomanage the network configurations and network management.Whenever there aremultiple sending devices inside the SDNnetwork,theOpenFlow switches are programmed to handle the limited number of requests for their interface.When the recommendations are exceeded from the specific threshold,the load on the switches also increases.This research article introduces a new approach named LBoBS to handle load balancing by adding the load balancing server to the SDN network.Besides,it is used to maximize SDN’s reliability and efficiency.It also works in coordination with the controller to effectively handle the load balancing policies.The load balancing server is implemented to manage the switches load effectively.Results are evaluated on the NS-3 simulator for packet delivery,bandwidth utilization,latency control,and packet decision ratios on the OpenFlow switches.It has been found that the proposed method improved SDN’s load balancing by 70%compared to the previous state-of-the-art methods.
基金supported by the Fundamental Research Funds for the Central Universities(2021RC239)the Postdoctoral Science Foundation of China(2021 M690338)+3 种基金theHainan Provincial Natural Science Foundation of China(620RC562,2019RC096,620RC560)the Scientific Research Setup Fund of Hainan University(KYQD(ZR)1877)the Program of Hainan Association for Science and Technology Plans to Youth R&D Innovation(QCXM201910)the National Natural Science Foundation of China(61802092,62162021).
文摘With the expansion of network services,large-scale networks have progressively become common.The network status changes rapidly in response to customer needs and configuration changes,so network configuration changes are also very frequent.However,no matter what changes,the network must ensure the correct conditions,such as isolating tenants from each other or guaranteeing essential services.Once changes occur,it is necessary to verify the after-changed network.Whereas,for the verification of large-scale network configuration changes,many current verifiers show poor efficiency.In order to solve the problem ofmultiple global verifications caused by frequent updates of local configurations in large networks,we present a fast configuration updates verification tool,FastCUV,for distributed control planes.FastCUV aims to enhance the efficiency of distributed control plane verification for medium and large networks while ensuring correctness.This paper presents a method to determine the network range affected by the configuration change.We present a flow model and graph structure to facilitate the design of verification algorithms and speed up verification.Our scheme verifies the network area affected by obtaining the change of the Forwarding Information Base(FIB)before and after.FastCUV supports rich network attributes,meanwhile,has high efficiency and correctness performance.After experimental verification and result analysis,our method outperforms the state-of-the-art method to a certain extent.
基金supported in part by the National Key R&D Program of China under Grant No.2017YFB0801701the National Science Foundation of China under Grant No.61472213CERNET Innovation Project(NGII20160123)
文摘Software defined networking(SDN)has attracted significant attention from both academia and industry by its ability to reconfigure network devices with logically centralized applications.However,some critical security issues have also been introduced along with the benefits,which put an obstruction to the deployment of SDN.One root cause of these issues lies in the limited resources and capability of devices involved in the SDN architecture,especially the hardware switches lied in the data plane.In this paper,we analyze the vulnerability of SDN and present two kinds of SDN-targeted attacks:1)data-to-control plane saturation attack which exhausts resources of all SDN components,including control plane,data plane,and the in-between downlink channel and 2)control plane reflection attack which only attacks the data plane and gets conducted in a more efficient and hidden way.Finally,we propose the corresponding defense frameworks to mitigate such attacks.
文摘Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation positioning and science exploration. In this paper, the architecture of Software Defined Space Optical Network (SDSON) based on cloud platform is designed by means of Software Defined Optical Network (SDON) and cloud services. The new architecture combining centralized and distributed management-control mechanism is a multi-layer and multi-domain architecture with powerful computing and storage ability. Moreover, reliable service and unreliable service communication models employed in the space information network are proposed considering the characteristic of Disruption/Delay Tolerant Network (DTN). Finally, the functional verification and demonstration are performed on our optical experimental network platform.
文摘Automatic Switched Optical network (ASON) is the key technology for the next generation optical networks, and the recommendations for ASON were also developed by ITU-T. However, the recommendations for the management plane have not been made yet. In this paper, the management information model for the resources of control plane is proposed based on the management requirements of ASON for the first time. The managed objects for control plane could be used for the management of control Network Elements(NEs) and control channels, they can also be used for route areas division in control plane, parameter configuration and performance inspection for the control modules in a control NEs.
基金National Natural Science Foundation of China (60572021, 60710047)the National Basic Research Program of China (2007CB310705)+3 种基金the Hi-Tech Research and Development Program of China (2006AA01Z243)NCET (06-0090), PCSIRT (IRT0609)ISTCP (2006DFA11040)111 Project (B07005)
文摘This article discusses the issue of resource conflict in the generalized multi-protocol label switching (GMPLS) controlled optical network. Based on the analysis of the current random rebuilding mechanism and its drawbacks, this article presents two enhanced solutions for improvement, namely, the priority-based resource allocation mechanism and the network management system (NMS) based sequential resource allocation mechanism. Experimental results show that the presented mechanisms perform better than the original random rebuilding solution in terms of the connection setup/recovery time and successful rate.
文摘The convergence of data and optical networks is a charming tendency of the current network evolution. In this paper, we propose a novel data and optical network integrating device. Based on it, a converging network structure is put forward and named Hierarchical Data and Optical Networking Integrating (HDONI) networking architecture.