Security Sector Information

What is the Security Sector?

The Security Sector, also known as the “SataDiskSecurityBlobSector” in the Xbox 360 system software, is a small blob of data located on Xbox 360 hard-drives. It contains various information about the hard-drive, such as the serial number, model information, and firmware revision. It also contains the “UserAddressableSectorCount”, which is what controls the amount of space the console is allowed to use.

In summary, it is the annoying blob of data that is stopping us from using any sized and different branded hard-drives.

Workarounds, Hacks, and Exceptions

The entire structure is signed with RSA, so it cannot be modified and expected to authenticate on a normal retail console successfully. Hence why we cannot have larger drive sizes. On boot, the console runs a check on the information inside of the Security Sector and checks to see that the information recorded matches the information inscribed in the drive’s firmware. If any values do not match, the console won’t recognize the drive. An application named HDDHacker is the only partial solution around this restriction. It modifies the firmware of certain (not all) hard-drives so it will match the information in a Security Sector. That way we can make cheaper and usable hard-drives.

UPDATE: As of 4/23/11, a better solution now exists!

For example, if you have a 500gb HDD with firmware that matches information in a valid Security Sector, the console will only use the space defined in the structure. So you will be losing a lot of space.

For SMC hacked consoles (JTAG), the need for a Security Sector has been removed in the default patch set in FreeBoot/XBR. Hence why we can use any hard-drive.

Development Kit hard-drives do not need Security Sectors.