The Experts below are selected from a list of 1851 Experts worldwide ranked by ideXlab platform
Pierrealexandre Bliman - One of the best experts on this subject based on the ideXlab platform.
-
lyapunov equation for the stability of linear delay systems of retarded and neutral type
IEEE Transactions on Automatic Control, 2002Co-Authors: Pierrealexandre BlimanAbstract:In this note, the delay-independent stability of delay systems is studied. It is shown that the strong delay-independent stability is equivalent to the feasibility of certain linear matrix inequality (LMI), that is to the existence of a quadratic Lyapunov-Krasovskii functional, independent of the (Nonnegative) Value of the delay. This constitutes the analogue of some well-known properties of finite-dimensional systems. This result is then applied to study delay-independent stability of systems with polytopic uncertainties.
-
Lyapunov Equation for the Stability of Linear Delay Systems of Retarded and Neutral Type
2001Co-Authors: Pierrealexandre BlimanAbstract:In this note is studied the delay-independent stability of delay systems. It is shown that the strong delay-independent stability is tantamount to the feasibility of certain linear matrix inequality, or equivalently to the existence of certain quadratic Lyapunov-Krasovskii functional, independent of the (Nonnegative) Value of the delay. This constitutes the analogue of some well-known properties of finite-dimensional systems. This result is then applied to study delay-independent stability of systems with commensurate delays, delay-independent stabilizability, and delay-indepen- dent stability of systems with polytopic uncertainties.
-
Robust absolute stability of delay systems
Nonlinear control in the Year 2000, 2001Co-Authors: Pierrealexandre BlimanAbstract:The present paper is devoted to the study of absolute stability of delay systems with nonlinearities subject to sector conditions, and with uncertain delays. We construct Lyapunov-Krasovskii functionals candidates for various such systems, whose decreasingness along the trajectories is expressed in terms of Linear Matrix Inequalities (LMIs). We then show that feasibility of the latter implies some frequency domain conditions, which express that circle or Popov criterion holds, whatever the Nonnegative Value of the delay (delay-independent criteria). Also, using a class of transformations of the system, one is able to provide LMI conditions under which circle or Popov criterion holds, whatever the Value of the delay in a certain compact interval containing zero (delay-dependent criteria).
Weijun Zhong - One of the best experts on this subject based on the ideXlab platform.
-
Configuration of intrusion prevention systems based on a legal user: the case for using intrusion prevention systems instead of intrusion detection systems
Information Technology and Management, 2018Co-Authors: Chuanxi Cai, Shue Mei, Weijun ZhongAbstract:An intrusion prevention system (IPS) acts as a new type of information security technology, the configuration and management of which are currently urgent problems; in particular, debate exists regarding the Value of these systems. In this paper, we analyse whether a firm realizes a positive or negative Value from using an IPS instead of an intrusion detection system (IDS) in a default configuration and an optimal configuration, respectively. Our results suggest: (a) an IPS could hurt the firm when not configured optimally; (b) the optimal configuration of the IPS depends not only on the cost parameters but also on the external environment (quality of the IDS) in which the firm is operating; (c) whether the IDS is optimally configured or not, the firm will make the same decisions between using the IPS instead of the IDS and continuing to use the IDS; and (d) except for the true positive rate of IDS being in a certain region and the blocking cost being sufficiently high, the firm realizes a strictly Nonnegative Value if the firm configures the IPS optimally.
Chuanxi Cai - One of the best experts on this subject based on the ideXlab platform.
-
Configuration of intrusion prevention systems based on a legal user: the case for using intrusion prevention systems instead of intrusion detection systems
Information Technology and Management, 2018Co-Authors: Chuanxi Cai, Shue Mei, Weijun ZhongAbstract:An intrusion prevention system (IPS) acts as a new type of information security technology, the configuration and management of which are currently urgent problems; in particular, debate exists regarding the Value of these systems. In this paper, we analyse whether a firm realizes a positive or negative Value from using an IPS instead of an intrusion detection system (IDS) in a default configuration and an optimal configuration, respectively. Our results suggest: (a) an IPS could hurt the firm when not configured optimally; (b) the optimal configuration of the IPS depends not only on the cost parameters but also on the external environment (quality of the IDS) in which the firm is operating; (c) whether the IDS is optimally configured or not, the firm will make the same decisions between using the IPS instead of the IDS and continuing to use the IDS; and (d) except for the true positive rate of IDS being in a certain region and the blocking cost being sufficiently high, the firm realizes a strictly Nonnegative Value if the firm configures the IPS optimally.
Srinivasan Raghunathan - One of the best experts on this subject based on the ideXlab platform.
-
the Value of intrusion detection systems in information technology security architecture
Information Systems Research, 2005Co-Authors: Huseyin Cavusoglu, Birendra K Mishra, Srinivasan RaghunathanAbstract:The increasing significance of information technology (IT) security to firms is evident from their growing IT security budgets. Firms rely on security technologies such as firewalls and intrusion detection systems (IDSs) to manage IT security risks. Although the literature on the technical aspects of IT security is proliferating, a debate exists in the IT security community about the Value of these technologies. In this paper, we seek to assess the Value of IDSs in a firm's IT security architecture. We find that the IDS configuration, represented by detection (true positive) and false alarm (false positive) rates, determines whether a firm realizes a positive or negative Value from the IDS. Specifically, we show that a firm realizes a positive Value from an IDS only when the detection rate is higher than a critical Value, which is determined by the hacker's benefit and cost parameters. When the firm realizes a positive (negative) Value, the IDS deters (sustains) hackers. However, irrespective of whether the firm realizes a positive or negative Value from the IDS, the IDS enables the firm to better target its investigation of users, while keeping the detection rate the same. Our results suggest that the positive Value of an IDS results not from improved detection per se, but from an increased deterrence enabled by improved detection. Finally, we show that the firm realizes a strictly Nonnegative Value if the firm configures the IDS optimally based on the hacking environment.
Shue Mei - One of the best experts on this subject based on the ideXlab platform.
-
Configuration of intrusion prevention systems based on a legal user: the case for using intrusion prevention systems instead of intrusion detection systems
Information Technology and Management, 2018Co-Authors: Chuanxi Cai, Shue Mei, Weijun ZhongAbstract:An intrusion prevention system (IPS) acts as a new type of information security technology, the configuration and management of which are currently urgent problems; in particular, debate exists regarding the Value of these systems. In this paper, we analyse whether a firm realizes a positive or negative Value from using an IPS instead of an intrusion detection system (IDS) in a default configuration and an optimal configuration, respectively. Our results suggest: (a) an IPS could hurt the firm when not configured optimally; (b) the optimal configuration of the IPS depends not only on the cost parameters but also on the external environment (quality of the IDS) in which the firm is operating; (c) whether the IDS is optimally configured or not, the firm will make the same decisions between using the IPS instead of the IDS and continuing to use the IDS; and (d) except for the true positive rate of IDS being in a certain region and the blocking cost being sufficiently high, the firm realizes a strictly Nonnegative Value if the firm configures the IPS optimally.
