从端点发送的单向消息，叫做通知。

A one-way message sent from an endpoint, called a notification.

youdao

两条单向消息可以用来建立请求／响应通信。

Two one-way messages can be used to establish request/response communications. To send a SOAP message with SMTP, you will need to perform the following steps

youdao

同样，客户端堆栈可能会通过不同的方式来解释单向消息。

Also, a client SOAP stack might interpret one-way messages differently.

youdao