Oracle Net Services provides enterprise-wide connectivity solutions in distributed, heterogeneous computing environments. Oracle Net Services eases the complexities of network configuration and management, maximizes performance, and improves network diagnostic capabilities.

Oracle Net, a component of Oracle Net Services, enables a network session from client application to an Oracle database server. Once a network session is established, Oracle Net acts as a data courier for the client application and the database server.

It is responsible for establishing and maintaining the connection between the client application and database server, as well as exchanging messages between them. Oracle Net is able to perform these jobs because it is located on each computer in the network. Network sessions are established with the help of a listener.

The listener is a separate process that resides on the database server. The listener receives incoming client connection requests and manages the traffic of these requests to the server. The listener brokers the client request, handing off the request to the server.

Every time a client requests a network session with a server, a listener receives the actual request. If the client's information matches the listener's information, the listener grants a connection to the server.