Answer the following RAID-based questions:

(a)What three common characteristics are shared by all RAID levels except RAIDO?

(b) Assume a 10-drive RAID configuration. Fill in the following matrix, by indicating the relative rank (i.e., 2^rd, 3^rd etc.) of each level under each performance metric, Note that the highest performing level under each metric is given in the table by the notation 1 (1^st) Please briefly justify your relative ranking.

RAID level	Storage Density	Bandwidth Performance	Transaction Performance	Redundancy (reliability)
0	1(1st)		1(1st)
3		1(1st)
5
6
10				1(1st)

Storage density refers to the fraction of disk storage available for user data (as opposed to parity data). Bandwidth performance reflects how fast data can be transferred out of an array. Transaction performance measures how many I/O operations per second an array can perform. Redundancy defines an arrays ability to tolerate disk failures (i.e., the more disk failures it can tolerate, the higher the arrays redundancy.).

A brief review of the above RAID levels are given below:

(1) RAID 0 has no redundancy and is sometimes nicknamed JBOD, for just a bunch of disks,although the data may be striped across the disks in the array.

(2) RAID 3 makes use of a parallel access technique in which all member disks of the array participate in the execution of every I/O request, with a single parity disk and data being bit-wise striped (i.e., bit-interleaved parity).

(3) RAID 5 and RAID 6 make use of an ndependent access technique in which each member disk of the array operates independently so that separate I/Os can be satisfied in parallel. The data are striped with a relatively large strip size in RAID 5 & 6. While RAID 5 can tolerate one disk failure, RAID 6 can tolerate two simultaneous disk failures.

(4) RAID 10 is a result of organizing mirrored pairs of disks, each pair being a RAID 1, into a RAID O (e.g., a 10-drive RAID 10 is an array of 5 RAID Is, with the data striped or distributed across the 5). Please provide your brief justifications for your ranking in the space below.