DDOS attacks mainly occur in the network layer. Its most obvious characteristic is to send a large number of attack packets, consume network bandwidth resources and affect normal users' access. At present, the detection and defense technology for DDOS attacks in the network layer is quite mature, and at the same time, some new attack methods-DDOS attacks in the application layer have emerged. Different from network layer DDOS attacks, application layer DDOS attacks mostly imitate the access behavior of legitimate users and will not generate a large number of attack data packets during data transmission, but they will consume server resources through a large number of database queries and other operations, which is more difficult to detect. According to the different attack modes, DDOS attacks include reflection amplification attacks in addition to ordinary flooding attacks. This type of attack often uses a legitimate server as a reflector, which sends a large number of data packets to the target, thus causing greater harm. At present, DDOS attacks against DNS servers are also common. Attackers often send fake domain names to DNS servers, consuming DNS server resources. At the same time, due to the recursive query mechanism in DNS servers, DDOS attacks against DNS servers have a large impact range.Two interfaces:Although the above code fulfills the requirements on the page, But our code is coupled together, At present, although there are not many problems, if SKU attributes become more and more with the change of demand in the future, for example, when one or more drop-down boxes are added to the page, it means selecting the memory of the mobile phone. Now we need to calculate the color, memory and purchase quantity to judge whether NextBTN shows insufficient inventory or puts it into the shopping cart. The code is as follows:Owing to the seriousness of the case, Investigators expanded the scope of their search. Through continuous investigation of the surroundings, investigators accidentally found three brightly colored plastic bags in Wenliang River on the west side of the scene. The bags were basically filled with domestic garbage. Under these scattered items, they found a bank card of a rural credit cooperative. The last bag contained clothes, both men's and women's. In a pair of men's jeans, the investigators found another Agricultural Bank subsistence allowance card with a signature on the back. After identification, the clothes in the bag were exactly the clothes the couple had worn in recent days. What was even more shocking was that the bag also contained the marriage certificates of the couple. This is a dangerous signal, and the investigators' foreboding is getting stronger and stronger. The top priority is to find out where the missing couple are.By the time it was over seven o'clock in the evening, We heard the door ring, We all stood up, I stood behind the door, The hostess pushed open the door of the small bedroom and came in. The woman came in and was surrounded by the four of us with knives. Zhao Mou held the woman's two arms and pressed the woman to the ground. I, Wang Jiying and Fu Gang rushed into the living room to control the male host. The male host picked up Mazazi and hit me. I blocked it with my left hand. Fu Gang and Wang Jiying rushed over and threatened the man with a knife, forcing the man to the southeast corner. They told the man to be honest and not to move. I asked Wang Jiying where the handcuffs were. Wang Jiying said that on the bed in the small bedroom, I ran to the small bedroom to bring back the handcuffs and handcuffed the man back.云影笑着对葫芦道：葫芦，你去催催秦瀚他们，捞够两碗就行了，别在水塘那磨蹭了。
