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Fuxiang Gao - One of the best experts on this subject based on the ideXlab platform.
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Analysis of a Delayed Internet Worm Propagation Model with Impulsive Quarantine Strategy
Mathematical Problems in Engineering, 2014Co-Authors: Yu Yao, Wenlong Xiang, Wei Yang, Xiaodong Feng, Fuxiang GaoAbstract:Internet worms exploiting zero-day vulnerabilities have drawn significant attention owing to their enormous threats to Internet in the real world. To begin with, a worm Propagation Model with time delay in vaccination is formulated. Through theoretical analysis, it is proved that the worm Propagation system is stable when the time delay is less than the threshold and Hopf bifurcation appears when time delay is equal to or greater than . Then, a worm Propagation Model with constant quarantine strategy is proposed. Through quantitative analysis, it is found that constant quarantine strategy has some inhibition effect but does not eliminate bifurcation. Considering all the above, we put forward impulsive quarantine strategy to eliminate worms. Theoretical results imply that the novel proposed strategy can eliminate bifurcation and control the stability of worm Propagation. Finally, simulation results match numerical experiments well, which fully supports our analysis.
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Modeling and analysis of bifurcation in a delayed worm Propagation Model
Journal of Applied Mathematics, 2013Co-Authors: Yu Yao, Wenlong Xiang, Nan Zhang, Fuxiang GaoAbstract:A delayed worm Propagation Model with birth and death rates is formulated. The stability of the positive equilibrium is studied. Through theoretical analysis, a critical value of Hopf bifurcation is derived. The worm Propagation system is locally asymptotically stable when time delay is less than . However, Hopf bifurcation appears when time delay passes the threshold , which means that the worm Propagation system is unstable and out of control. Consequently, time delay should be adjusted to be less than to ensure the stability of the system stable and better prediction of the scale and speed of Internet worm spreading. Finally, numerical and simulation experiments are presented to simulate the system, which fully support our analysis.
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hopf bifurcation in an internet worm Propagation Model with time delay in quarantine
Mathematical and Computer Modelling, 2013Co-Authors: Yu Yao, Fuxiang Gao, Hao Guo, Xiaowu Xie, Xiaojun TongAbstract:Abstract Internet worm attacks reduce network security and cause economic losses. The use of a quarantine strategy is prominent in defending against worms, and it has been applied to various worm Propagation Models. Although theoretical analysis suggests that worms must get eliminated under quarantine, such a result does not appear in a real network. The time delay considered in this paper, which is caused by the time window of the intrusion detection system (IDS) that exists in the Propagation system, is one of the main reasons for this. A worm Propagation Model with time delay under quarantine is constructed for practical application. The stability of the positive equilibrium and local Hopf bifurcation are discussed. By analysis, a critical value τ 0 of the Hopf bifurcation is derived. When the time delay is less than τ 0 , the worm Propagation system is stable and easy to predict; when it is equal to or greater than τ 0 , Hopf bifurcation appears. Since it is easy to control and eliminate worms under a simple and stable worm Propagation system without Hopf bifurcation, the time window of the IDS must be adjusted so that the time delay is less than τ 0 , which ensures that the worm Propagation system remains stable and that worms can be eliminated with certain containment strategy. Numerical results from our experiment support our theoretical analysis.
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discrete time simulation method for worm Propagation Model with pulse quarantine strategy
Procedia Engineering, 2011Co-Authors: Fuxiang Gao, Yu Yao, Hao GuoAbstract:Abstract In this paper, discrete-time simulation method for worm Propagation Model with pulse quarantine strategy is proposed. Such method is firstly applied to traditional Kermack-Mckendrick Model and is verified to be effective. Then, considering practical factors, worm Propagation Model with pulse quarantine strategy is simulated in the method. Through the comparison between numerical curves and simulation ones, discrete-time simulation method can well simulate worm Propagation under pulse quarantine strategy. Finally, the algorithm of the method is given and analyzed.
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The Worm Propagation Model with Pulse Quarantine Strategy
2010 International Conference on Multimedia Information Networking and Security, 2010Co-Authors: Yu Yao, Hao Guo, Fuxiang GaoAbstract:In this paper, a worm Propagation Model with pulse quarantine strategy is proposed to control the spread of the worm. This Model which combines both the pulse quarantine and the constant quarantine strategy not only describes the Propagation of the worm well and but also makes the infections eradicated effectively. Here, we show that there exits a stable infection-free periodic solution of the system and its stability condition is obtained. Finally, the numerical and simulation results of the pulse quarantine strategy is given, which indicate that the infections will get eliminated and the pulse quarantine policy has a nice performance on the worm control
Dushyanth Sirivolu - One of the best experts on this subject based on the ideXlab platform.
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a wave Propagation Model for the high velocity impact response of a composite sandwich panel
International Journal of Impact Engineering, 2010Co-Authors: M. S. Hoo Fatt, Dushyanth SirivoluAbstract:A solution methodology to predict the residual velocity of a hemispherical-nose cylindrical projectile impacting a composite sandwich panel at high velocity is presented. The term high velocity impact is used to describe impact scenarios where the projectile perforates the panel and exits with a residual velocity. The solution is derived from a wave Propagation Model involving deformation and failure of facesheets, through-thickness Propagation of shock waves in the core, and through-thickness core shear failure. Equations of motion for the projectile and effective masses of the facesheets and core as the shock waves travel through sandwich panel are derived using Lagrangian mechanics. The analytical approach is mechanistic involving no detail account of progressive damage due to delamination and debonding but changes in the load-bearing resistance of the sandwich panel due to failure and complete loss of resistance from the facesheets and core during projectile penetration. The predicted transient deflection and velocity of the projectile and sandwich panel compared fairly well with results from finite element analysis. Analytical predictions of the projectile residual velocities were also found to be in good agreement with experimental data.
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a wave Propagation Model for the high velocity impact response of a composite sandwich panel
International Journal of Impact Engineering, 2010Co-Authors: M. S. Hoo Fatt, Dushyanth SirivoluAbstract:A solution methodology to predict the residual velocity of a hemispherical-nose cylindrical projectile impacting a composite sandwich panel at high velocity is presented. The term high velocity impact is used to describe impact scenarios where the projectile perforates the panel and exits with a residual velocity. The solution is derived from a wave Propagation Model involving deformation and failure of facesheets, through-thickness Propagation of shock waves in the core, and through-thickness core shear failure. Equations of motion for the projectile and effective masses of the facesheets and core as the shock waves travel through sandwich panel are derived using Lagrangian mechanics. The analytical approach is mechanistic involving no detail account of progressive damage due to delamination and debonding but changes in the load-bearing resistance of the sandwich panel due to failure and complete loss of resistance from the facesheets and core during projectile penetration. The predicted transient deflection and velocity of the projectile and sandwich panel compared fairly well with results from finite element analysis. Analytical predictions of the projectile residual velocities were also found to be in good agreement with experimental data.
Yu Yao - One of the best experts on this subject based on the ideXlab platform.
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Analysis of a Delayed Internet Worm Propagation Model with Impulsive Quarantine Strategy
Mathematical Problems in Engineering, 2014Co-Authors: Yu Yao, Wenlong Xiang, Wei Yang, Xiaodong Feng, Fuxiang GaoAbstract:Internet worms exploiting zero-day vulnerabilities have drawn significant attention owing to their enormous threats to Internet in the real world. To begin with, a worm Propagation Model with time delay in vaccination is formulated. Through theoretical analysis, it is proved that the worm Propagation system is stable when the time delay is less than the threshold and Hopf bifurcation appears when time delay is equal to or greater than . Then, a worm Propagation Model with constant quarantine strategy is proposed. Through quantitative analysis, it is found that constant quarantine strategy has some inhibition effect but does not eliminate bifurcation. Considering all the above, we put forward impulsive quarantine strategy to eliminate worms. Theoretical results imply that the novel proposed strategy can eliminate bifurcation and control the stability of worm Propagation. Finally, simulation results match numerical experiments well, which fully supports our analysis.
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Modeling and analysis of bifurcation in a delayed worm Propagation Model
Journal of Applied Mathematics, 2013Co-Authors: Yu Yao, Wenlong Xiang, Nan Zhang, Fuxiang GaoAbstract:A delayed worm Propagation Model with birth and death rates is formulated. The stability of the positive equilibrium is studied. Through theoretical analysis, a critical value of Hopf bifurcation is derived. The worm Propagation system is locally asymptotically stable when time delay is less than . However, Hopf bifurcation appears when time delay passes the threshold , which means that the worm Propagation system is unstable and out of control. Consequently, time delay should be adjusted to be less than to ensure the stability of the system stable and better prediction of the scale and speed of Internet worm spreading. Finally, numerical and simulation experiments are presented to simulate the system, which fully support our analysis.
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hopf bifurcation in an internet worm Propagation Model with time delay in quarantine
Mathematical and Computer Modelling, 2013Co-Authors: Yu Yao, Fuxiang Gao, Hao Guo, Xiaowu Xie, Xiaojun TongAbstract:Abstract Internet worm attacks reduce network security and cause economic losses. The use of a quarantine strategy is prominent in defending against worms, and it has been applied to various worm Propagation Models. Although theoretical analysis suggests that worms must get eliminated under quarantine, such a result does not appear in a real network. The time delay considered in this paper, which is caused by the time window of the intrusion detection system (IDS) that exists in the Propagation system, is one of the main reasons for this. A worm Propagation Model with time delay under quarantine is constructed for practical application. The stability of the positive equilibrium and local Hopf bifurcation are discussed. By analysis, a critical value τ 0 of the Hopf bifurcation is derived. When the time delay is less than τ 0 , the worm Propagation system is stable and easy to predict; when it is equal to or greater than τ 0 , Hopf bifurcation appears. Since it is easy to control and eliminate worms under a simple and stable worm Propagation system without Hopf bifurcation, the time window of the IDS must be adjusted so that the time delay is less than τ 0 , which ensures that the worm Propagation system remains stable and that worms can be eliminated with certain containment strategy. Numerical results from our experiment support our theoretical analysis.
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discrete time simulation method for worm Propagation Model with pulse quarantine strategy
Procedia Engineering, 2011Co-Authors: Fuxiang Gao, Yu Yao, Hao GuoAbstract:Abstract In this paper, discrete-time simulation method for worm Propagation Model with pulse quarantine strategy is proposed. Such method is firstly applied to traditional Kermack-Mckendrick Model and is verified to be effective. Then, considering practical factors, worm Propagation Model with pulse quarantine strategy is simulated in the method. Through the comparison between numerical curves and simulation ones, discrete-time simulation method can well simulate worm Propagation under pulse quarantine strategy. Finally, the algorithm of the method is given and analyzed.
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stability analysis of p2p worm Propagation Model with dynamic quarantine defense
Journal of Networks, 2011Co-Authors: Wei Yang, Yu Yao, Guiran Chang, Xiaomeng ShenAbstract:The Propagation of P2P worm covers large area and causes great damage. A dynamic quarantine protocol is designed to quarantine the suspicious host in the P2P system. Then a mathematical Model of PWPQ is proposed which considering the dynamic process of peer joining and leaving. The effect of dynamic quarantine on active P2P worm is analyzed. Through stability analysis for PWPQ Model, a key argument of infection-free stable point which affect the P2P worm Propagation, the basic reproduction number, is deduced. Simulation results show that the Propagation Model of P2P worms can reflect the P2P worm behaviors and the performance of our Model is significantly better than other Models, in terms of decreasing the number of infected hosts and reducing the worm Propagation speed. When the basic reproduction number is less than 1, infection-free stable point is global stability and the P2P worm are eliminated. The PWPQ Model gives some way to control P2P worm break out and gives guidelines to P2P worm detection and defense.
M. S. Hoo Fatt - One of the best experts on this subject based on the ideXlab platform.
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a wave Propagation Model for the high velocity impact response of a composite sandwich panel
International Journal of Impact Engineering, 2010Co-Authors: M. S. Hoo Fatt, Dushyanth SirivoluAbstract:A solution methodology to predict the residual velocity of a hemispherical-nose cylindrical projectile impacting a composite sandwich panel at high velocity is presented. The term high velocity impact is used to describe impact scenarios where the projectile perforates the panel and exits with a residual velocity. The solution is derived from a wave Propagation Model involving deformation and failure of facesheets, through-thickness Propagation of shock waves in the core, and through-thickness core shear failure. Equations of motion for the projectile and effective masses of the facesheets and core as the shock waves travel through sandwich panel are derived using Lagrangian mechanics. The analytical approach is mechanistic involving no detail account of progressive damage due to delamination and debonding but changes in the load-bearing resistance of the sandwich panel due to failure and complete loss of resistance from the facesheets and core during projectile penetration. The predicted transient deflection and velocity of the projectile and sandwich panel compared fairly well with results from finite element analysis. Analytical predictions of the projectile residual velocities were also found to be in good agreement with experimental data.
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a wave Propagation Model for the high velocity impact response of a composite sandwich panel
International Journal of Impact Engineering, 2010Co-Authors: M. S. Hoo Fatt, Dushyanth SirivoluAbstract:A solution methodology to predict the residual velocity of a hemispherical-nose cylindrical projectile impacting a composite sandwich panel at high velocity is presented. The term high velocity impact is used to describe impact scenarios where the projectile perforates the panel and exits with a residual velocity. The solution is derived from a wave Propagation Model involving deformation and failure of facesheets, through-thickness Propagation of shock waves in the core, and through-thickness core shear failure. Equations of motion for the projectile and effective masses of the facesheets and core as the shock waves travel through sandwich panel are derived using Lagrangian mechanics. The analytical approach is mechanistic involving no detail account of progressive damage due to delamination and debonding but changes in the load-bearing resistance of the sandwich panel due to failure and complete loss of resistance from the facesheets and core during projectile penetration. The predicted transient deflection and velocity of the projectile and sandwich panel compared fairly well with results from finite element analysis. Analytical predictions of the projectile residual velocities were also found to be in good agreement with experimental data.
G Vavitsas - One of the best experts on this subject based on the ideXlab platform.
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a worm Propagation Model based on scale free network structures and people s email acquaintance profiles
2007Co-Authors: T Komninos, Paul G Spirakis, G VavitsasAbstract:In light of the rise of malicious attacks on the internet and the various networks and applications attached to it, new approaches towards Modeling worm activity in networks is called for. One frequently utilized method for W32/Novarg [7], Sober X, Netsky P and Mytob ED [18] Propagation exploited by worms is through the victim's contact book. The contact book, which reflects the acquaintance profiles of people, is used as a ``hit-list'', to which the worm can try and send itself in order to spread fast. In this paper we propose a discrete worm Propagation Model that relies upon a combined email and Instant Messaging (IM) communication behavior of users in a scale free environment. We also Model the effect in Propagation based on user reaction when a threat is recognized, the installation and update of antivirus software as well as the network connectivity, arising conclusions about the behavior of the network infrastructure in presence of a worm. Our analysis is based on Wormald's differential equations method for approximating ``well-behaving'' random processes with deterministic functions.
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a worm Propagation Model based on people s email acquaintance profiles
Lecture Notes in Computer Science, 2006Co-Authors: T Komninos, Yannis C Stamatiou, G VavitsasAbstract:One frequently employed way of Propagation exploited by worms is through the victim's contact book. The contact book, which reflects the acquaintance profiles of people, is used as a hit-list, to which the worm can send itself in order to spread fast. In this paper we propose a discrete worm Propagation Model that relies upon a combined email and Instant Messaging (IM) communication behaviour of users. We also Model user reaction against infected email as well as the rate at which antivirus software is installed. User acquaintance is perceived as a network connecting users based on their contact book links. We then propose a worm Propagation formulation based on a token Propagation algorithm, further analyzed with a use of a system of continuous differential equations, as dictated by Wormald's theorem on approximating well-behaving random processes with deterministic functions.
