Q46.Marks: +2.0UGC NET Paper 2: Computer Science17th June 2023
Match List I with List II
LIST I
LIST II
A.
RAID level 2
I.
Bit interleaved parity
B.
RAID level 4
II.
Block interleaved distributed parity
C.
RAID level 5
III.
Error correcting parity
D.
RAID level 3
IV.
Block interleaved parity
Choose the correct answer from the options given below:
1.A - IV, B - III, C - I, D - II
2.A - III, B - IV, C - II, D - I✓ Correct
3.A - III, B - I, C - II, D - IV
4.A - I, B - III, C - IV, D - I
Solution
The correct answer is A - III, B - IV, C - II, D - I
Key Points
RAID level 2 ( III - Error correcting parity):
RAID 2 uses an error-correcting code known as Hamming code, which is a set of parity bits for error detection and correction. Each bit of data is written to a separate disk drive in the array, and corresponding parity bits are written to additional drives, which allows the error correction to occur.
RAID level 4 (IV - Block interleaved parity):
In RAID 4, data is split into blocks and written across multiple drives in an array (i.e., block-level striping). But unlike other RAID levels, RAID 4 has a dedicated disk for storing parity information. This configuration allows for high read data transaction rates because the data blocks and the parity are stored on different drives.
The parity information, which is used for data redundancy, is not written to a single, dedicated drive as in RAID 4. Instead, it is interspersed across all the drives in the array. This leads to a system where read and write operations can occur simultaneously on multiple drives, improving overall performance compared to RAID 4.
RAID level 3 (I - Bit interleaved parity):
RAID 3 is similar to RAID 2 but it uses a simpler parity calculation. Data is split at the bit level and written across the drives in the array (i.e., bit-level striping) with parity being stored on a dedicated drive.
By matching RAID levels with their corresponding strategies, we get option 2 as the correct one: A - III, B - II, C - II, D - I.
