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Since http is based on tcp, You need to complete a three-way handshake to establish a tcp connection before you can start http communication, Therefore, when http flood attacks are carried out, it is not possible to use forged source ip addresses to launch attacks. An attacker will typically use an http proxy server, Not only can the source be hidden from being traced, It also improves attack efficiency-after the attacker connects to the proxy server and sends the request, You can directly disconnect from the proxy server and start connecting to the next proxy server, At this time, the http connection between the proxy server and the target web server is still maintained, and the web server needs to continue to accept and process data. An efficient http flood attack should continuously send http requests for different resources and pages, and request resources that cannot be cached as much as possible (such as keyword search. User-related information, etc.)　　以色列退伍士兵约亚夫（汤姆·梅西耶 饰），一心向往自由开放的法国，却在来到巴黎后惨遭洗劫。眼看即将沦落街头，约亚夫遇到一对生活富裕的情侣—作家艾米勒和女友卡洛琳，因而幸运获救。5.2. 5 Flatness Design Requirements约翰.卡特本是航空公司的保安人员，但没能保住妻子躲过劫匪的子弹。妻子的不幸死亡既使他痛苦，又令他沮丧。公司在配合联邦调查局押送劫机重犯时，故意安排已改任安全训练教师的卡特同机，怕的就是途中发生意外。果然，劫机犯同伙混上飞机杀了机长，欲驾机逃往别处。卡特果断将飞机汽油放掉，迫使飞机降落在路易斯安娜州一个小机场。当他向当地警方寻求支援时反被扣留。幸好联邦调查局探员及时赶到，将卡特送上已在跑道上开始滑行的飞机。在一场恶斗之后，卡特终于制服劫匪，再度让飞机安全降落。本片以近年来发生的十二起影响特别重大、案情复杂、侦破难度极大并成功侦破的刑事案件为背景，以纪实的风格、艺术地再现扑朔迷离，惊心动魄的侦查缉捕过程。《觅迹追踪》为“新警事”系列的第三部作品，该片集成了前两部快节奏、高密度的情节安排等特点，完全将美剧风格发挥的淋漓尽致，使其形成一涉案系列剧品牌。阀门厂老板周成龙失踪一天后，被人发现死在上村路一幢住宅内。死者的弟弟在案发后不知所踪，嫌疑重大。副队长诸葛智在案情调查中发现，死者刚离异的妻子周丽芳竟是自己的初恋女友，没想到婚后大款丈夫并没有给她带来几天的幸福。诸葛智认为此案情杀、仇杀的可能性极大，而队长陈海涛认为死者弟弟背后的那帮赌徒不仅有作案动机，也具备作案条件。对此，两种意见各执一词。红鼻子等赌徒被从广东捉拿回本市后，破案心切的王大鹏因刑讯逼供而被检察机关立案查处。经过两个多月的艰苦侦查，扑朔迷离的案情终于大白于天下，杀人凶手以及幕后主谋被缉拿归案……