You can configure a TCP connection to a DB system. For an Autonomous Database, you need to configure a TLS connection.
To establish a TCP connection between the target database and Oracle Data Safe during target database registration, the database must have both the network encryption and data integrity features enabled. The supported encryption algorithm is AES256. Supported cryptographic hash functions for checksum are SHA1, SHA256, SHA384, and SHA512. Non-encrypted TCP connections are not supported.