说明：  自己写的C# DOSS攻击实例 通过tcp 协议是3次握手的方式连接的，第一次客户机向服务器发送一个标志为syn的数据包，这个数据包的tcp部分有个16位随即序列号，而且ip部分和tcp部 分各有一个校验码，发送出去只有校验码正确才会视为合法的数据包，然后如果那个机器那个端口有服务器，比如http服务，就会把序列号+1，然后再生成一 个16位随机序列号，标志syn+ack的数据包返回，服务器就会占着一个信道等待第三次握手了，如果超过预定时间等不到就超时去掉了，这时如果开始那个 syn的源ip地址和源端口是伪造的并大量发送，服务器就会大量的向假ip端口返回syn+ack并等待，这样就大量占着信道了，如果超过了连接限制，别 的机器就连不上了，就拒绝服务了。原理大体就是这个样子了。
(Write your own C# DOSS attack instance handshake connection through tcp protocol, the first time the client sends to the server a flag for the syn packet, this packet tcp part of a 16 then the serial number, and ip part and tcp part one on each check code sent only correct checksum will be regarded as the legitimate packets, and then if that machine that port server, such as http service serial number will+1, then regenerated into a 16-bit random serial number, logo syn+ack packet returns, the server will occupy a channel exceeds a predetermined time less than a timeout to remove the wait for the third handshake, then if you start the syn source ip address and the source port and send a large number of forged server will be a lot of to fake ip port to return syn+ack and waiting for, so that a large number of occupied channel, if the connection limit is exceeded, the other machines on the crawl denial of service. Principle roughly like this.)