通过分析截获TCP报文首部信息，理解首部中的序号、确认号等字段是TCP可靠连接的基础。通过分析TCP连接的三次握手建立和释放过程，理解TCP连接建立和释放机制。-

Intercepted by analyzing the TCP packet header information to understand in the first serial number, confirmation number and other fields are the basis of the TCP reliable connection. Three times to shake hands through the Analysis of a TCP connection establishment and release process, understanding of TCP connection establishment