RAID Fault Tolerance (continued)
nRAID level 3: Similar
to RAID level 2, but error-correcting data is stored on only
one disk
nRAID level 4: Similar to RAID level 2, but
an added feature is checksum verification data stored on one
disk
nRAID level 5: Similar to RAID level 4, but
error-correction and checksum data are spread over all disks