BGP(Border Gateway Protocol)协议是Internet中应用最广泛的自治系统间路由协议,它通过面向连接的TCP(Transfer Control Protocol)协议保障路由信息的可靠转发。然而,以DDoS(Distributed Denial of Service)为代表的网络攻击对基于TCP...BGP(Border Gateway Protocol)协议是Internet中应用最广泛的自治系统间路由协议,它通过面向连接的TCP(Transfer Control Protocol)协议保障路由信息的可靠转发。然而,以DDoS(Distributed Denial of Service)为代表的网络攻击对基于TCP的应用协议产生了严重的威胁。保护BGP协议较为常见的方法是在网络边缘添加防火墙、流量分析仪等安全设备。从分析BGP邻居的建立过程及DDoS的攻击特点入手,提出一种新的思路,在不增加运营成本的前提下,实现BGP协议对DDoS的防御。展开更多
In order to overcome the disadvantages of diagonal connection structures that are complex and for which it is difficult to derive the discriminant of the airflow directions of airways, we have applied a multiple regre...In order to overcome the disadvantages of diagonal connection structures that are complex and for which it is difficult to derive the discriminant of the airflow directions of airways, we have applied a multiple regression method to analyze the effect, of changing the rules of mine airflows, on the stability of a mine ventilation system. The amount of air ( Qj ) is determined for the major airway and an optimum regression equation was derived for Qi as a function of the independent variable ( Ri ), i.e., the venti- lation resistance between different airways. Therefore, corresponding countermeasures are proposed according to the changes in airflows. The calculated results agree very well with our practical situation, indicating that multiple regression analysis is simple, quick and practical and is therefore an effective method to analyze the stability of mine ventilation systems.展开更多
The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conducti...The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conductivity coefficient of medium was developed on the basis of synthesis of numerical methods of the quasi-conformal mappings and summary representations in conjunction with domain decomposition by method Schwartz. The proposed algorithm allows finding the potential of the quasiideals field, construction a motion grid (fluid-flow grid) simultaneously defining the flow lines that separate of sub-domains constancy of coefficient conductivity and identification the piecewise-constant values of coefficient conductivity, the local flows for the known measurements on boundary of domain.展开更多
文摘BGP(Border Gateway Protocol)协议是Internet中应用最广泛的自治系统间路由协议,它通过面向连接的TCP(Transfer Control Protocol)协议保障路由信息的可靠转发。然而,以DDoS(Distributed Denial of Service)为代表的网络攻击对基于TCP的应用协议产生了严重的威胁。保护BGP协议较为常见的方法是在网络边缘添加防火墙、流量分析仪等安全设备。从分析BGP邻居的建立过程及DDoS的攻击特点入手,提出一种新的思路,在不增加运营成本的前提下,实现BGP协议对DDoS的防御。
基金Project F010206 supported by the National Natural Science Foundation of China
文摘In order to overcome the disadvantages of diagonal connection structures that are complex and for which it is difficult to derive the discriminant of the airflow directions of airways, we have applied a multiple regression method to analyze the effect, of changing the rules of mine airflows, on the stability of a mine ventilation system. The amount of air ( Qj ) is determined for the major airway and an optimum regression equation was derived for Qi as a function of the independent variable ( Ri ), i.e., the venti- lation resistance between different airways. Therefore, corresponding countermeasures are proposed according to the changes in airflows. The calculated results agree very well with our practical situation, indicating that multiple regression analysis is simple, quick and practical and is therefore an effective method to analyze the stability of mine ventilation systems.
文摘The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conductivity coefficient of medium was developed on the basis of synthesis of numerical methods of the quasi-conformal mappings and summary representations in conjunction with domain decomposition by method Schwartz. The proposed algorithm allows finding the potential of the quasiideals field, construction a motion grid (fluid-flow grid) simultaneously defining the flow lines that separate of sub-domains constancy of coefficient conductivity and identification the piecewise-constant values of coefficient conductivity, the local flows for the known measurements on boundary of domain.