Seagate ST500LX016 ユーザーズマニュアル

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EAGATE 

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LTRA 

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OBILE 

SSHD P

RODUCT 

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ANUAL

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  19

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BOUT 

(SED) S

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NCRYPTING 

D

RIVES 

The drive has a 32-byte hardware RNG that it is uses to derive encryption keys or, if requested to do so, to provide random numbers to the 

host for system use, including using these numbers as Authentication Keys (passwords) for the drive's Admin and Locking SPs.

In addition to changing the passwords, as described in 

, the owner should also set the data access controls 

for the individual bands.
The variable "LockOnReset" should be set to "PowerCycle" to ensure that the data bands will be locked if power is lost. In addition 

"ReadLockEnabled" and "WriteLockEnabled" must be set to true in the locking table in order for the bands "LockOnReset" setting of 

"PowerCycle" to actually lock access to the band when a "PowerCycle" event occurs. This scenario occurs if the drive is removed from its 

cabinet. The drive will not honor any data read or write requests until the bands have been unlocked. This prevents the user data from 

being accessed without the appropriate credentials when the drive has been removed from its cabinet and installed in another system.

When shipped from the factory, 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 additional bands (Band1 to Band15) by specifying a start LBA and an LBA 

range. The real estate for this band is taken from the Global Band.
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. The host may change the Encryption Key (see 

Section 5.6, Cryptographic 

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

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.

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.

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 

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

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

in 



Trusted Send



Trusted Receive

SED models will support the RevertSP 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.