Oracle Advanced Security Transparent Data Encryption Best Practices (White Paper)

Oracle White Paper
Oracle Advanced Security Transparent Data Encryption Best Practices

Introduction
This paper provides best practices for using Oracle Advanced Security Transparent Data Encryption (TDE). Oracle Advanced Security TDE provides the ability to encrypt sensitive application data on storage media completely transparent to the application itself. TDE addresses encryption requirements associated with public and private privacy and security mandates such as PCI and California SB1386. Oracle Advanced Security TDE column encryption was introduced in Oracle Database 10g Release 2, enabling encryption of application table columns, containing credit card or social security numbers. 
Oracle Advanced Security TDE tablespace encryption was introduced with Oracle Database 11gR1.

http://www.oracle.com/technetwork/database/security/twp-transparent-data-encryption-bes-130696.pdf