Seagate (ST16000NM002G) - Инструкция по эксплуатации - Страница 37

Seagate Exos X16 SAS Product Manual, Rev. K

36 

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About self-encrypting drives

8.5

Data bands

When shipped from the factor y, the drive is configured with a single data band called Band 0 (also  known as the Global Data Band) which

comprises LBA 0 through LBA max. The host may allocate Band1 by specifying a start LBA and an LBA range. The real estate for this band is taken

from the Global Band. An additional 30 Data Bands may be defined in a similar way (Band2 through Band31) but before these bands can be

allocated LBA space, they must first be individually enabled using the EraseMaster password.

Data bands cannot overlap but they can be sequential with one band ending at LBA (x) and the next beginning at LBA (x+1).

Each data band has its own drive-generated encryption key and its own user-supplied password. The host may change the Encryption Key (see

Section 8.6

) or the password when required. The bands should be aligned to 4K LBA boundaries.

8.6

Cryptographic erase

A significant feature of SEDs is the ability to perform a cryptographic erase. This involves the host telling the drive to change the data encryption

key for a particular band. Once changed, the data is no longer recoverable since it was written with one key and will be read using a different key. 
Since the drive overwrites the old key with the new one, and keeps no history of key changes, the user data can never be recovered. This  is 
tantamount to an instantaneous data erase and is very useful if the drive is to be scrapped or redispositioned. 

8.7

Authenticated firmware download

In addition to providing a locking mechanism to prevent unwanted firmware download attempts, the drive also only accepts download files 
which have been cryptographically signed by the appropriate Seagate Design Center.

Three conditions must be met before the drive will allow the download operation:

1.

The download must be an SED file. A standard (base) drive (non-SED) file will be rejected.

2.

The download file must be signed and authenticated.

3.

As with a non-SED drive, the download file must pass the acceptance criteria for the drive. For example it must be applicable to the correct 
drive model, and have compatible revision and customer status.

8.8

Power requirements

The standard drive models and the SED drive models have identical hardware, however the security and encryption portion of the drive controller 
ASIC is enabled and functional in the SED models. This represents a small additional drain on the 5V supply of about 30mA and a commensurate

increase of about 150mW in power consumption. There is no additional drain on the 12V supply. See the tables in 

Section 6.4

 for power 

requirements on the standard (non-SED) drive models.

8.9

Supported commands

The SED models support the following two commands in addition to the commands supported by the standard (non-SED) models as listed

in Table 

Table 7

:

• Security Protocol Out (B5h)
• Security Protocol In (A2h)

8.10

Sanitize - CRYPTOGRAPHIC ERASE

This command cryptographically erases all user data on the drive by destroying the current data encryption key and replacing it with a new data

encryption key randomly generated by the drive. Sanitize CRYPTOGRAPHIC ERASE is a SCSI CDB Op code 48h and selecting the service action

code 3 (CRYPTOGRAPHIC ERASE)

8.11

RevertSP

SED models will suppor t the Rever tSP feature which erases all data in all bands on the device and returns the contents of all SPs (Security

Providers) on the device to their original factory state. In order to execute the RevertSP method the unique PSID (Physical Secure ID) printed on

the drive label must be provided. PSID is not electronically accessible and can only be manually read from the drive label or scanned in via the 2D

barcode.