Level

Characteristics

0

Stripe Sets w/o parity - can use diff types of drives - 2 ore more drives - best performance but no fault-tolerance

*1

Mirroring & Duplexing - 2 sep drives - Best performance and the best fault-tolerance in a multi-user system.

2

This type uses striping across disks with some disks storing error checking and correcting (ECC) information. It has no advantage over RAID-3.

3

Parity written to one disk. best for single-user systems with long record applications.

*4

Independant disks with shared parity - high transaction rate and low ratio of ECC (parity) disks to data disks - writes parity across one disk - high efficiency - bad write transaction rate - 3 drive min - one disk parity disk

*5

Striping with parity - 3 drives needed -  Read Only efficient - writes parity across multiple disks - greater speed and redundancy

6

This type is similar to RAID-5 but includes a second parity scheme that is distributed across different drives and thus offers extremely high fault- and drive-failure tolerance. There are few or no commercial examples currently.

7

This type includes a real-time embedded operating system as a controller, caching via a high-speed bus, and other characteristics of a stand-alone computer. One vendor offers this system.

10

This type offers an array of stripes in which each stripe is a RAID-1 array of drives. This offers higher performance than RAID-1 but at much higher cost.

53

This type offers an array of stripes in which each stripe is a RAID-3 array of disks. This offers higher performance than RAID-3 but at much higher cost.