Transparent Data Encryption (SQL server 2008)

Transparent Data Encryption (TDE) is a new feature in SQL server 2008.
TDE is a new feature in SQL Server 2008; it provides real time encryption of data and log files. Data is encrypted before it is written to disk; data is decrypted when it is read from disk. The "transparent" aspect of TDE is that the encryption is performed by the database engine and SQL Server clients are completely unaware of it. There is absolutely no code that needs to be written to perform the encryption and decryption. There are a couple of steps to be performed to prepare the database for TDE, then the encryption is turned on at the database level via an ALTER DATBASE command.