Symmetric Keys (SQL Server)

A symmetric key is one key that is used for both encryption and decryption. Encryption and decryption by using a symmetric key is fast, and suitable for routine use with sensitive data in the database. PowerDesigner models symmetric keys as extended objects with a stereotype of <<SymmetricKey>>.

Creating a Symmetric Key

You can create a symmetric key in any of the following ways:

  • Select Model > Symmetric Keys to access the List of Symmetric Keys, and click the Add a Row tool.

  • Right-click the model (or a package) in the Browser, and select New > Symmetric Key.

Symmetric Key Properties

You can modify an object's properties from its property sheet. To open a symmetric key property sheet, double-click its diagram symbol or its Browser entry in the Symmetric Keys folder.

The following extended attributes are available on the Microsoft tab:

Name

Description

Authorization

Specifies the name of a user or role as the owner of the key.

Scripting name: Authorization

Certificate

Specifies the name of the certificate that will be used to encrypt the symmetric key.

Scripting name: Certificate

Password

Specifies a password from which to derive a TRIPLE_DES key with which to secure the symmetric key. Password complexity will be checked. You should always use strong passwords.

Scripting name: Password

Symmetric key

Specifies a symmetric key to be used to encrypt the key that is being created.

Scripting name: SymmetricKey

Asymmetric key

Specifies an asymmetric key to be used to encrypt the key that is being created.

Scripting name: AsymmetricKey

Key source

Specifies a pass phrase from which to derive the key.

Scripting name: KeySource

Algorithm

Specifies the algorithm used to encrypt the key

Scripting name: Algorithm

Identity value

Specifies an identity phrase from which to generate a GUID for tagging data that is encrypted with a temporary key.

Scripting name: IdentityValue