Certified Information Systems Security Professional (CISSP) Practice Exam

A mirrored set is characterized by the duplication of data across multiple disks to enhance reliability and availability. This configuration is what RAID 1 is designed to achieve. In RAID 1, data written to one disk is simultaneously copied to a second disk, thus creating an exact mirror of the data. This mirroring provides protection against data loss; if one disk fails, the system can continue to function using the other disk without any interruption to access.

The primary advantage of this configuration is its focus on redundancy rather than performance; while read speeds can be improved as multiple disks can be accessed simultaneously, the write speed may not see significant gains compared to other RAID levels. The capability for immediate access to a mirror of the data ensures that critical information remains intact even in the event of hardware failure.

In contrast, the other RAID configurations mentioned either do not offer mirroring (like RAID 0, which stripes data but provides no redundancy) or use combinations of striping and mirroring (like RAID 10, which combines RAID 1 and RAID 0) or parity calculations for redundancy (like RAID 6). None of these achieve the same level of straightforward data mirroring as RAID 1.