Transparent data encryption (TDE) helps you to secure your data at rest, this means the data files and related backups are encrypted, securing your data in case your media is stolen.
This technology works by implementing real-time I/O encryption and decryption, so this implementation is transparent for your applications and users.
However, this type of implementation could lead to some performance degradation since more resources must be allocated in order to perform the encrypt/decrypt operations.
On this post we will compare how much longer take some of the most common DB operations, so in case you are planning to implement it on your database, you can have an idea on what to expect from different operations.
These results fit in reasonably well with what I’d heard, but it’s nice to have someone run the numbers.