This image shows an OCI Region with an availability domain, a VCN, and two private subnets.

• The first private subnet hosts Oracle Cloud Infrastructure Functions and the apps within the Availability Domain, and a Stream Pool with OCI Streaming outside the domain.
• The second private subnet contains the Oracle Autonomous Database.

Outside the VCN, the OCI Region contains OCI Queue and Service Connector Hub.

The OCI Queue sends and receives messages with the apps and Oracle Cloud Infrastructure Functions through a Service Gateway on the VCN. The apps and Functions send and receive messages to and from the Stream Pool. The Service Connector Hub also receives messages from the Stream Pool and sends then to the database, passing each way through the service gateway on the VCN.