针对传统的IP欺骗攻击缓解方法存在运算开销大、缺乏灵活性等问题,提出了一种基于动态限制策略的软件定义网络(software defined network,SDN)中IP欺骗攻击缓解方法。首先,利用Packet-In消息中三元组信息回溯攻击路径,定位IP欺骗攻击源...针对传统的IP欺骗攻击缓解方法存在运算开销大、缺乏灵活性等问题,提出了一种基于动态限制策略的软件定义网络(software defined network,SDN)中IP欺骗攻击缓解方法。首先,利用Packet-In消息中三元组信息回溯攻击路径,定位IP欺骗攻击源头主机;然后,由控制器制定动态限制策略对连接攻击源头主机的交换机端口的新流转发功能进行限制,待限制期满再恢复其转发新流的功能,限制期的大小随着被检测为攻击源的次数而增长。研究结果表明:这种动态的限制策略可阻隔攻击流进入SDN网络,从而有效避免SDN交换机、控制器以及链路过载;由于在限制期间无需再对这些限制的交换机端口进行实时监测,该方法在应对长时攻击时较传统方法具有更高的缓解效率和更少的资源消耗。展开更多
A lot of routing algorithms have been proposed for low earth orbit（LEO） satellite IP networks in recent years,but most of them cannot achieve global optimization.The dynamic characters of LEO satellite networks are ...A lot of routing algorithms have been proposed for low earth orbit（LEO） satellite IP networks in recent years,but most of them cannot achieve global optimization.The dynamic characters of LEO satellite networks are reflected in two aspects：topology and traffic change.The algorithms mentioned above are ＂hard routing＂ which only realize local optimization.A distributed soft routing algorithm combined with multi-agent system（MASSR） is proposed.In MASSR,mobile agents are used to gather routing information actively,and blackboard is introduced to achieve direct information exchange between agents.MASSR provides traffic adaptive routing and tracks the change of LEO satellite network topology.The performance of ant colony optimization（ACO） and MASSR are compared in Iridium constellation,and MASSR presents better end-to-end delay as well as enhanced robustness.展开更多
Taking into chief consideration the features of aviation nodes in satellite networks, such as high moving speed, long communication distance, and high connection frequency, this article proposes an aviation-oriented m...Taking into chief consideration the features of aviation nodes in satellite networks, such as high moving speed, long communication distance, and high connection frequency, this article proposes an aviation-oriented mobility management method for IP/low earth orbit （LEO） satellite networks. By introducing the concept of ground station real-time coverage area, the proposed method uses ground-station-based IP addressing method and cell paging scheme to decrease the frequency of IP binding update requests as well as the paging cost. In comparison with the paging mobile IP （P-MIP） method and the handover-independent IP mobility management method, as is verified by the mathematical analysis and simulation, the proposed method could decrease the management cost. It also possesses better ability to support the aviation nodes because it is subjected to fewer influences from increased node speeds and newly coming connection rates.展开更多
In this paper we have designed an implemented an integrated framework of QoS for Three Level Mobility Model(TLMM),which has been recently proved to be the optimal mobility management solution for next generation wirel...In this paper we have designed an implemented an integrated framework of QoS for Three Level Mobility Model(TLMM),which has been recently proved to be the optimal mobility management solution for next generation wireless IP-based networks.The QoS solution uses a combination of IntServ and DiffServ models incorporated in TLMM architecture.The paper also proposes an effi cient dynamic handover policy that takes care of false handover.Simulation and analytical results have shown that this infrastructure guarantees eff icient QoS handling and scalability among end users.To provide a comparative understanding of the QoS mechanism and signaling load of TLMM we have used TeleMIP(without QoS support) and MIP as alternative mobility management protocols.展开更多
A new core-based shared tree algorithm,viz core-cluster combination-based shared tree(CCST)algorithm and the weighted version(i.e.w-CCST algorithm)are proposed in order to resolve the channel resources waste problem i...A new core-based shared tree algorithm,viz core-cluster combination-based shared tree(CCST)algorithm and the weighted version(i.e.w-CCST algorithm)are proposed in order to resolve the channel resources waste problem in typical source-based multicast routing algorithms in low earth orbit(LEO)satellite IP networks.The CCST algorithm includes the dynamic approximate center(DAC)core selection method and the core-cluster combination multicast route construction scheme.Without complicated onboard computation,the DAC method is uniquely developed for highly dynamic networks of periodical and regular movement.The core-cluster combination method takes core node as the initial core-cluster,and expands it stepwise to construct an entire multicast tree at the lowest tree cost by a shortest path scheme between the newly-generated core-cluster and surplus group members,which results in great bandwidth utilization.Moreover,the w-CCST algorithm is able to strike a balance between performance of tree cost and that of end-to-end propagation delay by adjusting the weighted factor to meet strict end-to-end delay requirements of some real-time multicast services at the expense of a slight increase in tree cost.Finally,performance comparison is conducted between the proposed algorithms and typical algorithms in LEO satellite IP networks.Simulation results show that the CCST algorithm significantly decreases the average tree cost against to the others,and also the average end-to-end propagation delay ofw-CCST algorithm is lower than that of the CCST algorithm.展开更多
Active Queue Management (AQM) is an active research area in the Internet community. Random Early Detection (RED) is a typical AQM algorithm, but it is known that it is difficult to configure its parameters and its ave...Active Queue Management (AQM) is an active research area in the Internet community. Random Early Detection (RED) is a typical AQM algorithm, but it is known that it is difficult to configure its parameters and its average queue length is closely related to the load level. This paper proposes an effective fuzzy congestion control algorithm based on fuzzy logic which uses the pre- dominance of fuzzy logic to deal with uncertain events. The main advantage of this new congestion control algorithm is that it discards the packet dropping mechanism of RED, and calculates packet loss according to a preconfigured fuzzy logic by using the queue length and the buffer usage ratio. Theo- retical analysis and Network Simulator (NS) simulation results show that the proposed algorithm achieves more throughput and more stable queue length than traditional schemes. It really improves a router's ability in network congestion control in IP network.展开更多
This paper mainly introduces about how to use socket to design network program which can transfer data in different network platform in terms of TCP/IP Network Programming Standard.
In this study,a real-time rotor temperature monitoring system for large turbogenerators using SmartMesh IP wireless network communication technology was designed and tested.The system is capable of providing comprehen...In this study,a real-time rotor temperature monitoring system for large turbogenerators using SmartMesh IP wireless network communication technology was designed and tested.The system is capable of providing comprehensive,accurate,continuous,and reliable real-time temperature monitoring for turbogenerators.Additionally,it has demonstrated satisfactory results in a real-time monitoring test of the rotor temperature of various famous large-scale turbogenerators and giant nuclear power half-speed turbogenerators designed and manufactured in China.The development and application of this wireless temperature measurement system would aid in improving the intelligent operation quality,safety,and stability of China’s large turbine generators and even the entire power system.展开更多
In order to meet the pressing demand for wide-area communication required by the Global Energy Interconnection(GEI),accelerating the construction of satellite-terrestrial Integra怕d networks that can achieve network e...In order to meet the pressing demand for wide-area communication required by the Global Energy Interconnection(GEI),accelerating the construction of satellite-terrestrial Integra怕d networks that can achieve network extension and seamless global coverage has become the focus of power communication tech no logy development.In this study,we propose a satellite-terrestrial integrated network model that can support interconnection and interoperation on the IP layer between the satellite system and the怕rrestrial segment of the existing power communication system.First,the composition and function of the satellite-terrestrial collaborative network are explained.Then,the IP-based protocol stack is described,and a typical applicati on experime nt is con ducted to illustrate the particular process of this protocol stack.Fin ally,a use case of IP interconn ection that depends on GEO satellite communication is detailed.The experime ntal study has showed that the satellite-terrestrial collaborative network can efficiently support various IP applications for the GEI.展开更多
In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of net...In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of networks varies significantly. This effect is thoroughly analyzed with a heuristic algorithm for different network topologies belonging to some European network operators. The main conclusion extracted is that limiting the transparent reach in such multi-layer networks can give a good tradeoff between CAPEX of IP/MPLS networks and WSON networks,and even lead to signifi cant savings in CAPEX when compared to longer lightpaths routing strategies.展开更多
A novel mechanism was specified by which a node in ad hoc network may autoconfigure an IP address which is unique throughout the mobile ad hoc network. This new algorithm imposes less and constant overhead and delay i...A novel mechanism was specified by which a node in ad hoc network may autoconfigure an IP address which is unique throughout the mobile ad hoc network. This new algorithm imposes less and constant overhead and delay in obtaining an IP address, and fully utilizes the available addresses space of an ad hoc network, and independent of the existing routing protocol, and less prone to security threats. Moreover, a new Join/Leave mechanism was proposed as an enhancement to the new IP address autoconfiguration algorithm, to support the overall operation of the existing routing protocol of wireless ad hoc networks.展开更多
In the internet protocol（IP） over multi-granular optical switch network （IP/MG-OXC）, the network node is a typical multilayer switch comprising several layers, the IP packet switching （PXC） layer, wavelength swi...In the internet protocol（IP） over multi-granular optical switch network （IP/MG-OXC）, the network node is a typical multilayer switch comprising several layers, the IP packet switching （PXC） layer, wavelength switching （WXC） layer and fiber switching （FXC） layer. This network is capable of both IP layer grooming and wavelength grooming in a hierarchical manner. Resource provisioning in the multi-granular network paradigm is called hierarchical grooming problem. An integer linear programming （ILP） model is proposed to formulate the problem. An iterative heuristic approach is developed for solving the problem in large networks. Case study shows that IP/MG-OXC network is much more extendible and can significantly save the overall network cost as compared with IP over wavelength division multiplexing network.展开更多
The quality of experience（ QoE） evaluation model for voice over IP（ VoI P） service is studied to analyze the impact of network parameters on voice quality and monitor voice quality in real-time for operators.First...The quality of experience（ QoE） evaluation model for voice over IP（ VoI P） service is studied to analyze the impact of network parameters on voice quality and monitor voice quality in real-time for operators.Firstly,the influence of some network parameters on the voice quality of VoI P is investigated. Then,a simulation platform for VoI P transmission is built to collect voice data under different network enviornments. According to the simulation results,a new mapping model between these arguments and VoI P voice quality is deduced. Finally,the accuracy of this voice quality evaluation model is examined and the results demanstrate that it has high reliability and feasibility.展开更多
In this paper,an algorithm Wireless Multimedia Transmission Control(WMTC) is proposed for multimedia transmission control over wired-wireless networks.The relationship between packet length and packet loss rate in the...In this paper,an algorithm Wireless Multimedia Transmission Control(WMTC) is proposed for multimedia transmission control over wired-wireless networks.The relationship between packet length and packet loss rate in the Gilbert wireless error model is investigated.Furthermore,the algorithm can detect the nature of packet losses by sending large and small packets alternately,and control the sending rate of nodes.In addition,by means of updating factor K,this algorithm can adapt to the changes of network states quickly.Compared with previous algorithms,simulation results show that WMTC can both improve the networks throughput of multimedia transmissions and reduce the congestion loss rate in various situations.展开更多
文摘针对传统的IP欺骗攻击缓解方法存在运算开销大、缺乏灵活性等问题,提出了一种基于动态限制策略的软件定义网络(software defined network,SDN)中IP欺骗攻击缓解方法。首先,利用Packet-In消息中三元组信息回溯攻击路径,定位IP欺骗攻击源头主机;然后,由控制器制定动态限制策略对连接攻击源头主机的交换机端口的新流转发功能进行限制,待限制期满再恢复其转发新流的功能,限制期的大小随着被检测为攻击源的次数而增长。研究结果表明:这种动态的限制策略可阻隔攻击流进入SDN网络,从而有效避免SDN交换机、控制器以及链路过载;由于在限制期间无需再对这些限制的交换机端口进行实时监测,该方法在应对长时攻击时较传统方法具有更高的缓解效率和更少的资源消耗。
基金supported by the National Natural Science Foundation of China (60532030)
文摘A lot of routing algorithms have been proposed for low earth orbit（LEO） satellite IP networks in recent years,but most of them cannot achieve global optimization.The dynamic characters of LEO satellite networks are reflected in two aspects：topology and traffic change.The algorithms mentioned above are ＂hard routing＂ which only realize local optimization.A distributed soft routing algorithm combined with multi-agent system（MASSR） is proposed.In MASSR,mobile agents are used to gather routing information actively,and blackboard is introduced to achieve direct information exchange between agents.MASSR provides traffic adaptive routing and tracks the change of LEO satellite network topology.The performance of ant colony optimization（ACO） and MASSR are compared in Iridium constellation,and MASSR presents better end-to-end delay as well as enhanced robustness.
基金National Natural Science Foundation of China (60532030)National Natural Science Foundation for Distinguished Young Scholars (60625102)
文摘Taking into chief consideration the features of aviation nodes in satellite networks, such as high moving speed, long communication distance, and high connection frequency, this article proposes an aviation-oriented mobility management method for IP/low earth orbit （LEO） satellite networks. By introducing the concept of ground station real-time coverage area, the proposed method uses ground-station-based IP addressing method and cell paging scheme to decrease the frequency of IP binding update requests as well as the paging cost. In comparison with the paging mobile IP （P-MIP） method and the handover-independent IP mobility management method, as is verified by the mathematical analysis and simulation, the proposed method could decrease the management cost. It also possesses better ability to support the aviation nodes because it is subjected to fewer influences from increased node speeds and newly coming connection rates.
文摘In this paper we have designed an implemented an integrated framework of QoS for Three Level Mobility Model(TLMM),which has been recently proved to be the optimal mobility management solution for next generation wireless IP-based networks.The QoS solution uses a combination of IntServ and DiffServ models incorporated in TLMM architecture.The paper also proposes an effi cient dynamic handover policy that takes care of false handover.Simulation and analytical results have shown that this infrastructure guarantees eff icient QoS handling and scalability among end users.To provide a comparative understanding of the QoS mechanism and signaling load of TLMM we have used TeleMIP(without QoS support) and MIP as alternative mobility management protocols.
基金National Natural Science Foundation of China(60532030,10577005,60625102)Innovation Foundation of Aerospace Science and Technology of China
文摘A new core-based shared tree algorithm,viz core-cluster combination-based shared tree(CCST)algorithm and the weighted version(i.e.w-CCST algorithm)are proposed in order to resolve the channel resources waste problem in typical source-based multicast routing algorithms in low earth orbit(LEO)satellite IP networks.The CCST algorithm includes the dynamic approximate center(DAC)core selection method and the core-cluster combination multicast route construction scheme.Without complicated onboard computation,the DAC method is uniquely developed for highly dynamic networks of periodical and regular movement.The core-cluster combination method takes core node as the initial core-cluster,and expands it stepwise to construct an entire multicast tree at the lowest tree cost by a shortest path scheme between the newly-generated core-cluster and surplus group members,which results in great bandwidth utilization.Moreover,the w-CCST algorithm is able to strike a balance between performance of tree cost and that of end-to-end propagation delay by adjusting the weighted factor to meet strict end-to-end delay requirements of some real-time multicast services at the expense of a slight increase in tree cost.Finally,performance comparison is conducted between the proposed algorithms and typical algorithms in LEO satellite IP networks.Simulation results show that the CCST algorithm significantly decreases the average tree cost against to the others,and also the average end-to-end propagation delay ofw-CCST algorithm is lower than that of the CCST algorithm.
基金Supported by the National High Technology Research and Development of China (863 Program) (No.2003AA121560)the High Technology Research and Development Program of Jiangsu Province (No.BEG2003001).
文摘Active Queue Management (AQM) is an active research area in the Internet community. Random Early Detection (RED) is a typical AQM algorithm, but it is known that it is difficult to configure its parameters and its average queue length is closely related to the load level. This paper proposes an effective fuzzy congestion control algorithm based on fuzzy logic which uses the pre- dominance of fuzzy logic to deal with uncertain events. The main advantage of this new congestion control algorithm is that it discards the packet dropping mechanism of RED, and calculates packet loss according to a preconfigured fuzzy logic by using the queue length and the buffer usage ratio. Theo- retical analysis and Network Simulator (NS) simulation results show that the proposed algorithm achieves more throughput and more stable queue length than traditional schemes. It really improves a router's ability in network congestion control in IP network.
文摘This paper mainly introduces about how to use socket to design network program which can transfer data in different network platform in terms of TCP/IP Network Programming Standard.
基金supported by the National Natura Science Foundation of China (NSFC), No.51607146China National Major Science and Technology Projects 2010ZX06004-013-04-02 and 2012ZX06002-017-02-01+1 种基金Sichuan Science and Technology Program,No.2018GZ0391Sichuan Hydropower Energy and power equipment technology Engineering Research Center, Xihua university, Chengdu 610039, China,No.SDNY2020-001
文摘In this study,a real-time rotor temperature monitoring system for large turbogenerators using SmartMesh IP wireless network communication technology was designed and tested.The system is capable of providing comprehensive,accurate,continuous,and reliable real-time temperature monitoring for turbogenerators.Additionally,it has demonstrated satisfactory results in a real-time monitoring test of the rotor temperature of various famous large-scale turbogenerators and giant nuclear power half-speed turbogenerators designed and manufactured in China.The development and application of this wireless temperature measurement system would aid in improving the intelligent operation quality,safety,and stability of China’s large turbine generators and even the entire power system.
基金supported by the State Grid Science and Technology Project (No. 5455HT160004)
文摘In order to meet the pressing demand for wide-area communication required by the Global Energy Interconnection(GEI),accelerating the construction of satellite-terrestrial Integra怕d networks that can achieve network extension and seamless global coverage has become the focus of power communication tech no logy development.In this study,we propose a satellite-terrestrial integrated network model that can support interconnection and interoperation on the IP layer between the satellite system and the怕rrestrial segment of the existing power communication system.First,the composition and function of the satellite-terrestrial collaborative network are explained.Then,the IP-based protocol stack is described,and a typical applicati on experime nt is con ducted to illustrate the particular process of this protocol stack.Fin ally,a use case of IP interconn ection that depends on GEO satellite communication is detailed.The experime ntal study has showed that the satellite-terrestrial collaborative network can efficiently support various IP applications for the GEI.
基金jointly supported by Jiangsu Government Scholarship for Overseas studies,Chinathe open fund of State Key Laboratory of Advanced Optical Communication Systems and Networks, Shanghai Jiao Tong University,China(No. 2015GZKF03006)Research Center of Optical Communications Engineering & Technology,Jiangsu Province(No.ZSF0201)
文摘In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of networks varies significantly. This effect is thoroughly analyzed with a heuristic algorithm for different network topologies belonging to some European network operators. The main conclusion extracted is that limiting the transparent reach in such multi-layer networks can give a good tradeoff between CAPEX of IP/MPLS networks and WSON networks,and even lead to signifi cant savings in CAPEX when compared to longer lightpaths routing strategies.
文摘A novel mechanism was specified by which a node in ad hoc network may autoconfigure an IP address which is unique throughout the mobile ad hoc network. This new algorithm imposes less and constant overhead and delay in obtaining an IP address, and fully utilizes the available addresses space of an ad hoc network, and independent of the existing routing protocol, and less prone to security threats. Moreover, a new Join/Leave mechanism was proposed as an enhancement to the new IP address autoconfiguration algorithm, to support the overall operation of the existing routing protocol of wireless ad hoc networks.
基金Sponsored by Agency for Singapore Technology and Advance Research(RGM01/16)
文摘In the internet protocol（IP） over multi-granular optical switch network （IP/MG-OXC）, the network node is a typical multilayer switch comprising several layers, the IP packet switching （PXC） layer, wavelength switching （WXC） layer and fiber switching （FXC） layer. This network is capable of both IP layer grooming and wavelength grooming in a hierarchical manner. Resource provisioning in the multi-granular network paradigm is called hierarchical grooming problem. An integer linear programming （ILP） model is proposed to formulate the problem. An iterative heuristic approach is developed for solving the problem in large networks. Case study shows that IP/MG-OXC network is much more extendible and can significantly save the overall network cost as compared with IP over wavelength division multiplexing network.
基金Supported by China National S&T Major Project(2012ZX03001034MCM 201240113)
文摘The quality of experience（ QoE） evaluation model for voice over IP（ VoI P） service is studied to analyze the impact of network parameters on voice quality and monitor voice quality in real-time for operators.Firstly,the influence of some network parameters on the voice quality of VoI P is investigated. Then,a simulation platform for VoI P transmission is built to collect voice data under different network enviornments. According to the simulation results,a new mapping model between these arguments and VoI P voice quality is deduced. Finally,the accuracy of this voice quality evaluation model is examined and the results demanstrate that it has high reliability and feasibility.
基金Supported by National Natural Science Foundation of China (No.60972038)the Jiangsu Province Universities Natural Science Research Key Grant Project (07KJA 51006)+1 种基金the Open Research Fund of National Mobile Communications Research Laboratory (N200911)Jiangsu Province Graduate Innovative Research Plan (CX09B_149Z)
文摘In this paper,an algorithm Wireless Multimedia Transmission Control(WMTC) is proposed for multimedia transmission control over wired-wireless networks.The relationship between packet length and packet loss rate in the Gilbert wireless error model is investigated.Furthermore,the algorithm can detect the nature of packet losses by sending large and small packets alternately,and control the sending rate of nodes.In addition,by means of updating factor K,this algorithm can adapt to the changes of network states quickly.Compared with previous algorithms,simulation results show that WMTC can both improve the networks throughput of multimedia transmissions and reduce the congestion loss rate in various situations.
