Symmetric keys

Chapter 15 DBMS-Specific Features

Symmetric keys

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 Key Objects to access the List of Symmetric Keys, and click the Add a Row tool
Right-click the model or 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 Key Objects folder.

The following extended attributes are available on the Microsoft tab:

Name	Scripting Name	Description
Authorization	Authorization	Specifies the name of a user or role as the owner of the key.
Certificate	Certificate	Specifies the name of the certificate that will be used to encrypt the symmetric key.
Password	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.
Symmetric key	SymmetricKey	Specifies a symmetric key to be used to encrypt the key that is being created.
Asymmetric key	AsymmetricKey	Specifies an asymmetric key to be used to encrypt the key that is being created.
Key source	KeySource	Specifies a pass phrase from which to derive the key.
Algorithm	Algorithm	Specifies the algorithm used to encrypt the key
Identity value	IdentityValue	Specifies an identity phrase from which to generate a GUID for tagging data that is encrypted with a temporary key.