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10.5 Security Feature Set
Security Feature Set is a powerful security feature. With a device lock password, a user can prevent unauthorized
access to hard disk device even if the device is removed from the computer.
The following commands are supported for this feature.
Security Set Password
(‘F1’h)
Security Unlock
(‘F2’h)
Security Erase Prepare
(‘F3’h)
Security Erase Unit
(‘F4’h)
Security Freeze Lock
(‘F5’h)
Security Disable Password
(‘F6’h)
Execution of these commands is restricted for the Trusted Computing Group feature set. That is, these commands
operate only in the state that is the Manufactured-Inactivate state by the Trusted Computing Group feature set.
Moreover, these commands are aborted in the state that is activated to the Manufactured state by the Trusted
Computing Group feature set.
10.5.1 Security Mode
Following security modes are provided.
Device Locked mode
The device disables media access commands after power on. Media access commands
are enabled by either a security unlock command or a security erases unit command.
Device Unlocked mode
The device enables all commands. If a password is not set this mode is entered after
power on, otherwise it is entered by a security unlock or a security erases unit command.
Device Frozen mode
The device enables all commands except those which can update the device lock
function, set/change password. The device enters this mode via a Security Freeze Lock
command. It cannot exit this mode until power off.
10.5.2 Security Level
Following security levels are provided.
High level security
When the device lock function is enabled and the User Password is forgotten the device
can be unlocked via a Master Password.
Maximum level security
When the device lock function is enabled and the User Password is forgotten then only
the Master Password with a Security Erase Unit command can unlock the device. Then
user data is erased.
10.5.3
Password
This function can have 2 types of passwords as described below.
Master Password
When the Master Password is set, the device does NOT enable the Device Lock Function,
and the device CANNOT be locked with the Master Password, but the Master Password
can be used for unlocking the device.
Identify Device Information Word 92 contains the value of the Master Password Revision
Code set when the Master Password was last changed. Valid values are 0001h through
FFFEh.
User Password
The User Password should be given or changed by a system user. When the User
Password is set, the device enables the Device Lock Function, and then the device is
locked on next power on reset or hard reset.
The system manufacturer/dealer who intends to enable the device lock function for the end users, must set the master
password even if only single level password protection is required.
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Hard Disk Drive Specification