The exponential growth of the Internet coupled with the increasing popularity of dynamically generated content on the World Wide Web, has created the need for more and faster Web servers capable of serving the over 10...The exponential growth of the Internet coupled with the increasing popularity of dynamically generated content on the World Wide Web, has created the need for more and faster Web servers capable of serving the over 100 million Internet users. To converge the control method has emerged as a promising technique to solve the Web QoS problem. In this paper, a model of adaptive session is presented and a session flow self regulating algorism based on Kalman Filter are proposed towards Weh Server. And a Web QoS self-regularing scheme is advanced. To attain the goal of on-line system identification, the optimized estimation of QoS parameters is fulfilled by utilizing Kalman Filter in full domain, The simulation results shows thal the proposed scheme can guarantee the QoS with both robusmess and stability .展开更多
Distributed denial of service （DDoS） attacks exploit the availability of Web servers, resulting in the severe loss of their connectivity. We present a robust IP packets filtering mechanism which combines the detecti...Distributed denial of service （DDoS） attacks exploit the availability of Web servers, resulting in the severe loss of their connectivity. We present a robust IP packets filtering mechanism which combines the detection and filtering engine together to protect Web Servers from DDoS Attacks. The mechanism can detect DDoS attacks by inspecting inbound packets with an IP address database, and filter out lower priority IP addresses to preserve the connection for valid users by monitoring the queues status. We use the Netfilter＇s technique, a framework inside the Linux 2.4. X, to implement it on a Web server. Also, we evaluate this mechanism and analyze the influence of some important parameters on system performance. The experimental results show that this mechanism is effective against DDoS attacks.展开更多
基金Supported by the National Natural Science Funda-tion of China (60272024) ,the National Natural Science Foundation ofHenan Province (0411014100)
文摘The exponential growth of the Internet coupled with the increasing popularity of dynamically generated content on the World Wide Web, has created the need for more and faster Web servers capable of serving the over 100 million Internet users. To converge the control method has emerged as a promising technique to solve the Web QoS problem. In this paper, a model of adaptive session is presented and a session flow self regulating algorism based on Kalman Filter are proposed towards Weh Server. And a Web QoS self-regularing scheme is advanced. To attain the goal of on-line system identification, the optimized estimation of QoS parameters is fulfilled by utilizing Kalman Filter in full domain, The simulation results shows thal the proposed scheme can guarantee the QoS with both robusmess and stability .
基金Supported by the National Natural Science Foun-dation of China (60373075 ,60473055)
文摘Distributed denial of service （DDoS） attacks exploit the availability of Web servers, resulting in the severe loss of their connectivity. We present a robust IP packets filtering mechanism which combines the detection and filtering engine together to protect Web Servers from DDoS Attacks. The mechanism can detect DDoS attacks by inspecting inbound packets with an IP address database, and filter out lower priority IP addresses to preserve the connection for valid users by monitoring the queues status. We use the Netfilter＇s technique, a framework inside the Linux 2.4. X, to implement it on a Web server. Also, we evaluate this mechanism and analyze the influence of some important parameters on system performance. The experimental results show that this mechanism is effective against DDoS attacks.
