【摘要】 随着互联网的迅速普及和应用的不断发展,各种黑客工具和网络攻击手段也随之倍出,网络攻击导致网络和用户受到侵害,其中分布式拒绝服务DDoS以其攻击范围广、隐蔽性强、简单有效等特点成为常见的网络攻击技术之一,极大地影响网络和业务主机系统的有效服务。其中的TCP DDoS它利用了传统协议中三次握手协议的不安全性,向互联网服务器发送大量的报文。由于服务器接收大量无效的报文,而使得正常的报文无法得到及时响应。如何检测这种攻击发生以及如何降低这种攻击所带来的后果已成为目前安全界研究的热点问题。更多还原

【Abstract】 With Internet popularized quickly and its application developing,more and more all kinds of hacker’s tools and network attack measures are appearing.Network attacks damaged networks and users,among which DDoS(Distributed Denial of Service) attacks become one of the common network attack techniques by the characteristics,such as extensive area,strong concealment,simpleness and efficiency,etc. DDoS attacks greatly affected the effective service of network and host systems.The SYN Flood which makes use of the insecurity of three-way handshake of the tradition TCP/IP protocol sends large number of SYN packets to Internet server.Becuse the server receive much useless SYN packets,the normal SYN packets can not response in time.Thus how to detect the attack and reduce the damage of this attack has become the topic of network security research throughout the world at present.更多还原