Chapter 15 DBMS-Specific Features


Asymmetric keys

An asymmetric key is made up of a private key and the corresponding public key. Each key can decrypt data encrypted by the other. Asymmetric encryption and decryption are relatively resource-intensive, but they provide a higher level of security than symmetric encryption. An asymmetric key can be used to encrypt a symmetric key for storage in a database. PowerDesigner models OBJECTS as extended objects with a stereotype of <<AsymmetricKey>>.

Creating an asymmetric key

You can create an asymmetric key in any of the following ways:

Asymmetric key properties

You can modify an object's properties from its property sheet. To open an asymmetric key property sheet, double-click its diagram symbol or its Browser entry in the Asymmetric Key Objects folder.

The following extended attributes are available on the Microsoft tab:

Name Description
Authorization Specifies the name of a user as the owner of the asymmetric key.

Scripting name: Authorization
Assembly Specifies the name of an assembly from which to load the public key.

Scripting name: Assembly
Assembly file Specifies the path of a file from which to load the key.

Scripting name: AssemblyFile
Algorithm Specifies the algorithm used to encrypt the key

Scripting name: Algorithm
Encryption password Specifies the password with which to encrypt the private key. If this clause is not present, the private key will be encrypted with the database master key.

Scripting name: EncryptionPassword

 


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