When a new TCP connection comes in from a client by means of a packet with the SYN bit set, the server creates an entry for the half-open connection and responds with a SYN-ACK packet.

当从客户机发来新的TCP连接时，数据包设置了SY n位，服务器就为这个半开的连接创建一个条目，并用一个SYN - ACK数据包进行响应。

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For one-way messages, the destination soap stack needs to generate a new soap envelope (with an empty soapenv: Body) in order to add this ack header.

对于单向消息，目的地soap堆栈需要生成一个新的soap信封(包含一个空的soapenv： Body)来添加这个ACK标签。

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