This image shows a diagram of the public and private subnets in Oracle Cloud Infrastructure, and how you can access the instances in these subnets using the Oracle Cloud Infrastructure network components.

There are three main boxes of varying sizes, which are on the same horizontal plane.

The first box has three icons. These icons are represent: Your Existing Network, Customer-Premises Equipment (CPE), and Dynamic Routing Gateway (DRG). An arrow points from Your Existing Network to Customer-Premises Equipment. Another arrow points from Customer-Premises Equipment to Dynamic Routing Gateway (DRG). This arrow represents the IPSec VPN. An arrow points from the DRG to a router that connects the DRG to Oracle Cloud Infrastructure (Region).

The second box is labeled Oracle Cloud Infrastructure (Region). It shows a Virtual Cloud Network (VCN). Two boxes in the VCN are placed one below the other to represent Availability Domain 1 and Availability Domain 2.

In Availability Domain 1, two boxes represent Public Subnet 1 (172.16.1.0/24) and Private Subnet 1 (172.16.2.0/24). Within Public Subnet 1 are two icons that represent web servers. Within Private Subnet 1 are two icons that represent database servers.

In Availability Domain 2, two boxes represent Public Subnet 2 (172.16.3.0/24) and Private Subnet 2 (172.16.4.0/24). Within Public Subnet 2 are two icons that represent web servers. Within Private Subnet 2 sub-box are two icons which represent database servers. The servers in Availability Domain 2 are redundant servers.

An arrow from the router, which establishes communication between the DRG and VCN, points to the Private Subnet 1 in Availability Domain 1, and to Private Subnet 2 in Availability Domain 2. A line from this router points to a table with four cells labeled Route Table #2: Private Subnet Route Table. The heading row of this table is labeled Destination CIDR and Route Target. The following row contains 0.0.0.0/0 and DRG as the text.

The third box has two icons. These icons represent the Internet Gateway and the External Web Client. An arrow points from the External Web Client to the Internet Gateway. Another arrow points from the Internet Gateway to a router that establishes communication between the Internet Gateway to Oracle Cloud Infrastructure (Region). An arrow from this router points to Public Subnet 1 in Availability Domain 1, and to Public Subnet 2 in Availability Domain 2. A line from this router points to a table with four cells labeled Route Table #1: Public Subnet Route Table. The heading row of this table is labeled Destination CIDR and Route Target. The following row contains 0.0.0.0/0 and Internet Gateway as the text.