Oracle当客户端与Oracle服务创建连接后，是客户端与Oracle服务器端直接通信的，此时并不会再跟listener打交道了，这个花了好久才把同事说服，这里通过文档的来记录下。是Oracle产生一个ServerProcess与客户端通信，监听只负责通知oracle有客户端需要连接并且这个连接是合法的或者安全的，通知Oracle你赶紧生产一个ServerProcess来提供服务吧。

文档原文：

Database Net Services Administrator's Guide->1 Introducing Oracle Net Services下的

1.2.2 About Oracle Net Listener

Oracle Database server receives the initial connection through Oracle Net Listener. Oracle Net Listener,referred to in this document as the listener,brokers a client request,handing off the request to the server. The listener is configured with a protocol address,and clients configured with the same protocol address can send connection requests to the listener. When a connection is established,the client and Oracle server communicate directly with one another.

文档中的图也可以说明：

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