block of data to be encrypted, which may slow down the data stream to the device and will increase CPU loading on the Media Server.

Encryption passphrase / Verify Passphrase

The user-supplied portion of the encryption key. Data Protector Express will use this value, along with other information it generates, to calculate an encryption key for the media. The passphrase must be entered twice to minimize the change of making a mistake while typing.

Hint

The text entered here will be added to the log file of an import job if the media later needs to be imported and the incorrect passphrase is supplied. Use this field to create a reminder of the passphrase because Data Protector Express cannot recover a lost passphrase.

Key Management

Data Protector Express has adopted a very simple key management strategy. A media is encrypted originally by configuring the job that creates it according to the parameters described above. From that point on, the media is known to the catalog. As long as the media is known, restore jobs may use the media without entering the passphrase again. If a media is unknown — because it was deleted from the catalog or because it came from a different catalog — you must import the media to make it known to the catalog again. The import process required you to supply the passphrase to complete the import. If the passphrase supplied does not match that used to encrypt the media, then the hint supplied at encryption time will be shown in the job log so you can try the import again.

When media is encrypted the media is depicted on the Jobs and Media view with a lock on it. The Platinum colored lock indicates hardware, whereas the gold lock indicates software encryption. The Media details window shows the type of encryption used.

Compression

Software encryption disables hardware compression, although you will still be able to select Software compression.

If the backup device has hardware compression then performance will be better if only hardware compression is used, and that there is little to no benefit of having both enabled. Enabling software compression in this circumstance will reduce performance.

If Hardware encryption is selected, HP recommends that Enable hardware compression is also selected. Hardware encryption and hardware compression can be used on devices, such as the HP LTO-4 tape drive, without loss of backup speed.

42 Encryption and Compression