DbDefence uses hardware optimized AES-128 or AES-256 encryption to completely encrypt your database, log and files on filestream media.

You can encrypt a database by using:

All methods will produce the same result. However, the GUI version runs several simple tests to double check the database integrity and protection after the encryption process.

Unlocking access

After the encryption process, DbDefence will deny any attempted access to the database until the correct password is supplied. An encrypted database contains a symmetric key called dbdx. To access the database, you will need to open that key with the following SQL Server statement:


If you drop that key from the string you will not be able to access the database. However, you do also have the option to decrypt the database and re-encrypt it. To decrypt the database you must know the password and have the corresponding key files. Here, you can Read more about accessing a protected database.

Accessing a database from Applications.

If a database is encrypted with access restriction then you need to open access for each connection. If you are a developer you can do this by inserting SQL statements in your code. For web applications and everything that runs in an IIS environment there is an additional option. For Reporting Services there is a special data source.


Any backups created from a protected database are also encrypted. There are several things you need to know about the backup and restore process. Please read the Backup section for more information.

Key files

For each encrypted file, DbDefence creates a key file with an extension .dbd_key. If you copy the database to another server you must copy the corresponding key files as well. Without the key files, it will be impossible to attach them to a SQL Server. If you distribute the database, you need to distribute all key files as well. Read more about the distribution process.

Free Version Limitation

The free version can be used in commercial projects freely. However, the Free Version has a limited database size of up to 200 Mb. Read more about obtaining the full version.