Introduction

Encryption is a very important security mechanism used to enforce confidentiality of data. There are two types of encryption that can be used in the Oracle Database. The first type is application-based encryption, which is implemented using the DBMS_CRYPTO PL/SQL package (this type is not covered in this book), and the second type is Transparent Data Encryption (TDE). TDE is a part of Advanced Security option of Oracle Database Enterprise Edition. It can be used to encrypt data in rest (table columns and tablespaces inside the database) and in transit (network, Recovery Manager (RMAN) backups, and Data Pump Exports).

The word transparent in Transparent Data Encryption means that application is not aware that data is encrypted in any way. In other words, application will never see the encrypted data-if user is not authorized to see the data, error (for example, insufficient privileges, table, or view does not exist) will be shown. The only way that a user will see encrypted data...