User Manual

Enterprise Self-Encrypting Drive User’s Guide, Rev. B 22
We do not have to (nor are we allowed to) manipulate the size of band 0. The drive will automatically give up storage
space from band 0 to accommodate the new bands we allocate. If we wanted to de-allocate band 1, we would simply
set its range to zero and the drive would return the space to the global band. Band 0 is the only band allowed to be
discontinuous. In Figure 13 we see that band 0 occupies LBAs 0 - 15, 40 – 55, and 64 – 99. Allocated bands may be
defined such that one ends at LBA (n) and the next starts at LBA (n+1), but they may not overlap. Bands must start at a
4 kilobyte sector boundary and since sectors (LBAs) are 512 bytes in length, the start LBA of a data band must be
exactly divisible by 8.
A sample dialogue between the drive and the host to set up the data bands on a new drive is shown in Figure 16. Here
BandMasterX is simply used as shorthand to represent any one of the data bands other than the global band.
For example, if the drive had 16 available data bands (including the global band 0), the ‘X’ would take any value from
1 through 15. To set up a data band, the first thing you have to do is to authenticate to the BandMaster authority
using the current value of the password. If this is a new drive, we know that this defaults to MSID. With that done, the
drive knows that you are a bona fide user and allows you to access the parameters associated with that band. This lets
you set the band’s start LBA (RangeStart) and its size (RangeLength) as well as the condition of its locking parameters
ReadLockEnabled, WriteLockEnabled, and LockOnReset. If you were not intending to use the band and would prefer it
to be locked at this time, you could set the ReadLocked and WriteLocked parameters to TRUE. Finally, you select a new
password value for BandmasterX (replacing the value of MSID) to keep the band private to your use.
Figure 14. Setting up a data band
Notice early in the flow chart that if you decide not to use this band, it is still good practice to personalize the pass-
word. This prevents someone else from gaining access to the band (using MSID) and locking you out.
Now that we’ve covered the groundwork, let’s summarize the rules and characteristics governing data bands.