Using a Distributed Denial of Service (DDoS) attack, hacktivists make websites inaccessible using botnets, and overwhelming the target site with server requests.

利用分布式拒绝服务（DDoS）攻击，激进黑客使用僵尸网络和用服务器请求淹没目标网站的方式，让网站无法访问。

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If the server CPU and memory seem to be running excessively high, the Domino Web logs should be checked for a Denial of Service type of attack.

如果服务器CPU和内存的运用率极高，那么应该检查Domino Web日志是否存在拒绝服务型攻击。

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XKMS server adopts synchronous processing mode, using SSL protocol to insure the security of message transmission, employs two-phase request protocol to protect against denial of service attack.

XKMS服务采用同步消息的传输模式，以SSL协议保证消息传递的安全性，以两阶段请求协议来防止拒绝服务攻击。

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Within hours, according to the cybersecurity researchers at Panda Labs, the loose group of hackers that calls itself Anonymous launched a distributed denial of service attack that threw junk traffic at the web server of the blog that had made the WikiLeaks announcement, and by 4am had taken the site offline.

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"The name server that is authoritative for Microsoft's Web sites might have crippled under a Denial of Service attack, " he said.

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