示例代码  

```
# UML
```

时序图  

```
```sequence
Title:
```

==连接建立的过程==  
==客户主机==`-\>`==服务器主机==`:` ==连接请求（==`SYN=1,seq=client_isn`==）==  
==服务器主机==`-\>`==客户主机==`:` ==授予连接（==`SYN=1,seq=client_isn`==）==`\n ack=client_isn+1`  
==客户主机==`-\>`==服务器主机==`:` ==确认（==`SYN=0,seq=client_isn+1`==）==

```
\n ack=server_isn+1
```
```

可参考文献:https://www.jianshu.com/p/5221380c65db