This paper presents a dynamic probabilistic marking algorithm with multiple routing address tags, which allows the vic- tim to traceback the origin of ICMP （Internet Control Message Pro- tocol）-based direct and refl...This paper presents a dynamic probabilistic marking algorithm with multiple routing address tags, which allows the vic- tim to traceback the origin of ICMP （Internet Control Message Pro- tocol）-based direct and reflective DoS attacks. The proposed ap- proach makes full use of scalable data space of ICMP packet to achieve multiple information tags. The difference between this pro- posal and previous proposals lies in two points. First, the number of packets needed by the victim to reconstruct the attack path is greatly reduced because of three key mechanisms： multi-tag, uniform left- over probability, and tag location choice based on the module of accommodated tag numbers within a packet. Second, the true origin of both direct and reflective ICMP-based DoS attacks can be traced.展开更多
In this paper, a cascade Sigma-Delta (ΣΔ) Analog to Digital Converter (ADC) for multistandard radio receiver was presented. This converter is supposed to be able to support GSM, UMTS, Wifi and WiMAX communication st...In this paper, a cascade Sigma-Delta (ΣΔ) Analog to Digital Converter (ADC) for multistandard radio receiver was presented. This converter is supposed to be able to support GSM, UMTS, Wifi and WiMAX communication standards. The Sigma-Delta modulator makes use of 4 bit quantizer and Data-Weighted-Averaging (DWA) technique to attain high linearity over a wide bandwidth. A top-down design methodology was adopted to provide a reliable tool for the design of reconfigurable high-speed ΣΔMs. VHDL-AMS language was used to model the analog and mixed parts of the selected 2-1-1 cascade ΣΔ converter and to verify their reconfiguration parameters based on behavioural simulation. This multistandard architecture was high level sized to adapt the modulator performance to the different standards requirements. The effects of circuit non-idealities on the modulator performance were modeled and analyzed in VHDLAMS to extract the required circuit parameters.展开更多
In wireless networks, jamming attacks are easy to launch and can significantly impact the network performance. The technique which localizes the jamming attacker is useful to address this problem. Some range-based loc...In wireless networks, jamming attacks are easy to launch and can significantly impact the network performance. The technique which localizes the jamming attacker is useful to address this problem. Some range-based localization schemes depend on the additional hardware of wireless nodes too much, and they can not work in resource-constrained wireless networks. Solutions in range-free localization are being pursued as a cost-effective alternative to more expensive range-based approaches.In this paper, we propose a novel range-free algorithm to localize the source of the attacker. We show that our approach only relies on the positions of each jammed or no-jammed node in the network, PSO algorithm is used to get the minimum covering circle of jammed positions and the circle center is the estimated jammer location. We compare our work with some existing range-free solutions via extensive simulations in two models, which are wireless sensor network (WSN) and vehicular ad hoc network (VANET) respectively. The experimental results suggest that our proposed algorithm achieves higher accuracy than the other solutions, and the localization error goes down with larger number of recorded jammed positions. In additional, when the recorded jammed positions are distributed in a specific constrained area, the localization error goes higher, we also propose an improved PSO algorithm to deal with this issue.展开更多
基金Supported by the National Natural Science Foundation of China(61271316)National Key Basic Research Program of China(973 Program)(2010CB731403)Opening Project of State Key Laboratory for Manufacturing Systems Engineering of Xi’an Jiaotong University(sklms2012005)
文摘This paper presents a dynamic probabilistic marking algorithm with multiple routing address tags, which allows the vic- tim to traceback the origin of ICMP （Internet Control Message Pro- tocol）-based direct and reflective DoS attacks. The proposed ap- proach makes full use of scalable data space of ICMP packet to achieve multiple information tags. The difference between this pro- posal and previous proposals lies in two points. First, the number of packets needed by the victim to reconstruct the attack path is greatly reduced because of three key mechanisms： multi-tag, uniform left- over probability, and tag location choice based on the module of accommodated tag numbers within a packet. Second, the true origin of both direct and reflective ICMP-based DoS attacks can be traced.
文摘In this paper, a cascade Sigma-Delta (ΣΔ) Analog to Digital Converter (ADC) for multistandard radio receiver was presented. This converter is supposed to be able to support GSM, UMTS, Wifi and WiMAX communication standards. The Sigma-Delta modulator makes use of 4 bit quantizer and Data-Weighted-Averaging (DWA) technique to attain high linearity over a wide bandwidth. A top-down design methodology was adopted to provide a reliable tool for the design of reconfigurable high-speed ΣΔMs. VHDL-AMS language was used to model the analog and mixed parts of the selected 2-1-1 cascade ΣΔ converter and to verify their reconfiguration parameters based on behavioural simulation. This multistandard architecture was high level sized to adapt the modulator performance to the different standards requirements. The effects of circuit non-idealities on the modulator performance were modeled and analyzed in VHDLAMS to extract the required circuit parameters.
文摘In wireless networks, jamming attacks are easy to launch and can significantly impact the network performance. The technique which localizes the jamming attacker is useful to address this problem. Some range-based localization schemes depend on the additional hardware of wireless nodes too much, and they can not work in resource-constrained wireless networks. Solutions in range-free localization are being pursued as a cost-effective alternative to more expensive range-based approaches.In this paper, we propose a novel range-free algorithm to localize the source of the attacker. We show that our approach only relies on the positions of each jammed or no-jammed node in the network, PSO algorithm is used to get the minimum covering circle of jammed positions and the circle center is the estimated jammer location. We compare our work with some existing range-free solutions via extensive simulations in two models, which are wireless sensor network (WSN) and vehicular ad hoc network (VANET) respectively. The experimental results suggest that our proposed algorithm achieves higher accuracy than the other solutions, and the localization error goes down with larger number of recorded jammed positions. In additional, when the recorded jammed positions are distributed in a specific constrained area, the localization error goes higher, we also propose an improved PSO algorithm to deal with this issue.
