What is Disk mirroring, Bit level stripping and block level stripping

Disk mirroring or shadowing:
Disk mirroring or shadowing is the process whereby each disk has a shadow or mirror disk. In the shadow or mirror disks data is written to simultaneously. Disk mirroring used to backup purposes and it is costly. In disk mirroring the data is duplicated on 2nd disk. If one disk fails or destroyed we can recover the original data from  2nd disk. Given below the picture of disk mirroring.

disk_mirroring

Bit level Stripping:
With multiple disk, we can improve transfer rate by striping data across multiple disk. When we split data bits across multiple disk, we call it bit level striping.
Block level stripping: 
When we split data bits across multiple disk, we call it block level striping.

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