The image shows secure connectivity between a Google Cloud Region to an Oracle RAC database in an OCI Region through a firewall, Oracle Connection Manager (CMAN), and Oracle Notification Server. The Google Cloud region, has a Client host in the Client Network connected to the Internet.

The Internet connects to a Firewall, which marks the entry to the OCI Region. Within the OCI Region, there are two networks:

Oracle Connection Manager (CMAN) Network

Contains a CMAN Host with a CMAN.
An Oracle Notification Service with an ONS Proxy.
The Firewall routes connects to both the CMAN Host and the Oracle Notification Service.
The CMAN Host connects to a RAC public network Sqlnet port 1521.
The ONS Proxy in Oracle Notification Service connects to RAC public network, ONS messages port 6200.

Database Network

Hosts Oracle Grid Infrastructure with the following:
- Oracle Real Application Clusters (Oracle RAC) database.
- Oracle Notification Server.
The CMAN Host and ONS Proxy are connected to Oracle Grid Infrastructure components.