How do I perform encryption with SQL Server?

Starting with SQL Server 2005 Encryption is now natively supported inside SQL Server.

In previous versions of SQL Server, despite rumors of "undocumented" cryptography functions in SQL Server (pwdencrypt() and pwdcompare()), these functions are not the symmetric encryption routines you want to use in a robust application. Using those functions does not provide reversible encryption and uses algorithms and key management you are not privy to. It is recommended that you implement encryption carefully based on the type of data you are looking to protect. Examples:

Field-Level (Protecting individual data fields)

• www.safelogic.com/en_safejdbc
• www.protegrity.com
• dbEncrypt
• www.aspencrypt.com
• CryptoAPI
• www.activecrypt.com
• www.netlib.com

File-Level (Protecting MDF's, backups, etc)

• www.sqllitespeed.com
• www.netlib.com
• Encrypted File System

Transport-Level

• Native SQL Server SSL encryption
• IPSec
• Multi-protocol net-lib