The following figure shows the Oracle Key Vault in the center connected by TLS to the following components, reading clockwise from the top:
At the top is Oracle Data Guard. It connects to Oracle Key Vault using TLS.
Next is an Oracle RAC environment. It connects using TLS to Oracle Key Vault.
Next is an Oracle GoldenGate environment, which also uses a TLS connection to Oracle Key Vault.
Next is a single database instance, also using a TLS connection to Oracle Key Vault.
The final component is an environment with multiple databases on the same computer, also using a TLS connection to Oracle Key Vault.