Which port number is used for Oracle Database connections?

Which port number is used for Oracle Database connections?

• A. 1701
• B. 1433
• C. 1521
• D. 1900

Answer: (C)

The main idea here is that Oracle Database connections go through the Oracle Net Listener, which by default listens on port 1521. When a client wants to connect, it specifies the host and port of the listener (for example, host:1521) along with the service name, and the listener accepts the connection and hands it off to the appropriate database service. This is why 1521 is the standard port for Oracle connections. If the listener is configured to use a different port, clients must use that port in their connect descriptor, and the change is made in the listener configuration. The other ports listed correspond to different services: 1433 is typically used by Microsoft SQL Server, 1701 is associated with certain VPN protocols, and 1900 is used by UPnP.

The main idea here is that Oracle Database connections go through the Oracle Net Listener, which by default listens on port 1521. When a client wants to connect, it specifies the host and port of the listener (for example, host:1521) along with the service name, and the listener accepts the connection and hands it off to the appropriate database service. This is why 1521 is the standard port for Oracle connections.

If the listener is configured to use a different port, clients must use that port in their connect descriptor, and the change is made in the listener configuration. The other ports listed correspond to different services: 1433 is typically used by Microsoft SQL Server, 1701 is associated with certain VPN protocols, and 1900 is used by UPnP.