SYN attack is a kind of DOS attack. It takes advantage of TCP protocol defects and consumes CPU and memory resources by sending a large number of semi-connection requests. SYN attacks can not only affect hosts, but also harm network systems such as routers and firewalls. In fact, SYN attacks can be implemented as long as these systems turn on TCP services no matter what systems are targeted. As can be seen from the above figure, the server receives the connection request (syn=j), adds this information to the unconnected queue, and sends the request packet to the client (syn=k, ack=j+1), then enters the SYN_RECV state. When the server does not receive an acknowledgement packet from the client, it retransmits the request packet and does not delete this entry from the non-connection queue until the timeout. With IP spoofing, SYN attacks can achieve good results, Typically, clients forge a large number of non-existent IP addresses in a short period of time, SYN packets are continuously sent to the server, and the server replies to the confirmation packets and waits for the confirmation of the customer. Since the source address does not exist, the server needs to continuously resend until it timeout. These forged SYN packets will occupy the unconnected queue for a long time, normal SYN requests will be discarded, the target system will run slowly, and in serious cases, the network will be blocked or even the system will be paralyzed.
Fourth: We must pay attention to the cost of icebergs when spending money.
04 日清戦争
RST means reset, which is used to close the connection abnormally. It is indispensable in TCP design. When sending RST packets to close the connection, you don't have to wait for all the packets in the buffer to be sent out (unlike the FIN packets above), and you directly send RST packets to discard the packets in the buffer. After receiving the RST packet, the receiving end does not need to send an ACK packet to confirm it.
Link: https://www.zhihu.com/question/44712155/answer/98597003
但是又有哪一家影视公司，肯让李英杰第一次出演，就出演一部大制作的男一号？他们不敢，因为他们没有那个眼光，更没有那个魄力。
弗兰德饰演詹姆斯·怀特豪斯，是一位雄心勃勃，富有魅力的初级部长，一直以来分享着妻子的好运。米勒饰演他的妻子苏菲，牛津大学毕业，育有两个孩子，看似完美的生活即将被引爆。道克瑞饰演主攻性犯罪的刑事律师＆王室法律顾问凯特·伍德克罗夫特，她在自己的领域迅速崛起，刚刚接手了一个百年难遇的案子。
继位不久的年轻皇帝朱允虽少年英武，大智大慧，却有些愁眉不展。朝外有三藩(云南王，齐国公，蓟州侯)势力逐渐坐大隐患，朝中有舅舅文章把持朝政，宫中有文章之女文媚儿专横跋扈，太后又对这个侄女宠爱过度。朱允虽为皇帝，却大权旁落，内忧外患使宫中的他十分不自在。于是他想方设法出宫查民心、访民情，同时也让自己享受些自由时光。
The principle of rescuing the wounded is to save people first, and the principle of rescuing people is to stop bleeding first.
郑在咏将出演在国立科学搜查研究院工作了10年的法医白范。他虽然是公认的实力派,但却是性格冷漠并执着于看不见的真相的天才和怪人。
"What was your first reaction when you saw these flying insects?" Asked
影片根据Anders Roslund 和Börge Hellström所著的瑞典畅销小说《Three Seconds》改编，讲述男主角Pete Hoffman是一个革新的罪犯以及前“特殊行动”组织的士兵，为了从监狱里释放出去和妻子女儿团聚，他参与了一项FBI组织的卧底任务，试图深入波兰毒贩集团在纽约的一桩交易，在这个过程中，他将回到自己试图摆脱束缚的Bale Hill监狱，而当一桩毒品交易出现差错，他的卧底身份也遭到曝光的可能... 影片由意大利演员、导演安德里亚·迪·斯戴法诺执导，其它卡司还有克里夫·欧文和美国说唱艺术家Common，目前正在前期制作中。
离异的中年男人赵凌（赵燕国彰 饰）为了治愈多年来的失眠，雇佣了坐台小姐斯娅（王子文 饰）伴自己入眠，不久更提出要花巨款买下后者的第一次出台……数年以后，赵凌与斯娅再次相遇在人海，此时仍然保有处子自身的斯娅已经爱上了一个陶艺师陶冶（王玉众 饰），陶冶在清查人口时为斯娅解围，而这个单纯的青年艺术家令斯娅的爱慕之心渐起，于是她进入了他的生活，但二人的情感之路充满坎坷，多年后重新出现的赵凌、陶冶对于斯娅三陪身份的嫌恶、还有来自陶冶乡下母亲的逼婚不时考验着二人。而陶冶大学好友一段充满了欺骗与欲望的爱情亦对照出陶冶与斯娅的坚定……
该剧讲述因为一个选择而改变了现在的命运爱情故事。结婚5年的柱赫和瑞珍因为预想不到的事情，命运发生了变化，在180度反转的现在以全新的面貌再次相遇而书写的奇幻罗曼史。此外，该剧以银行为背景，也将描写银行职员的日常等温暖的故事。池晟饰演结婚5年、入行6年的银行代理人车柱赫，是一个平凡却没有不满足之处的韩国普遍的职场人士。韩志旼饰演徐友珍，她很年轻就体验了结婚生子，边工作边带小孩，对现实感到疲惫以及对比起家庭更注重自己的工作的丈夫柱赫的气愤，让她甚至有了情绪调节障碍。之后，因为回到过去的柱赫做了不一样的选择，她迎来了全新的人生。《Oh我的鬼神大人》、《举重妖精金福珠》编剧+《购物王路易》、《帝王之女守百香》PD，预计下
那么，就投入一些时间精力，放在传承上吧
Change-up and Matching Zone
胡家一句话，我郑家也被抄了。
第二季的故事紧接着第一季，在Finch（迈克尔·爱默生 Michael Emerson 饰）被神秘的Root小姐绑架以后，“西装男”John Reese（詹姆斯·卡维泽 James Caviezel 饰）只得求助于他在纽约警局凶杀科的侦探朋友们Carter（塔拉吉·P·汉森 Taraji P. Henson 饰）以及Fusco（凯文·查普曼 Kevin Chapman 饰）的帮助，经过缜密调查，终于将Finch救出，却被Root逃脱。看似恢复如初的生活，其实暗藏危机。除了，一心想要把Finch的程序公开化的Root以外，他们还要找出HR真正的幕后黑手。另一方面，联邦调查局和中央情报局都在不遗余力地想要找出John。只要机器存在一天，这个城市仿佛从来不让他们休息........
The newly trained classifier is compared with the previous classifier to estimate how much change has taken place. For example, you can perform a dark launch and compare two outputs over the same traffic. Alternatives include A/B testing and backtracking testing for a small portion of traffic.
非洲大地丧尸肆虐，联合国军队也束手无策只能迅速撤离，此时美军中校墨菲因为飞机失事而流落此地，面对成群的饥饿丧尸墨菲只能在这广袤无垠的非洲大地中展开最后的求生逃亡……
