What technique can be used to protect against node/disk failures without storing two copies of data?

What technique can be used to protect against node/disk failures without storing two copies of data?

• A. Simple backup
• B. Data archiving
• C. Erasure Coding
• D. Data compression

Answer: (C)

Erasure coding is a method used to ensure data reliability and availability while minimizing storage overhead. It works by breaking down the original data into smaller fragments, generating additional redundant fragments through algorithms, and then storing these fragments across different nodes or disks. This technique allows the system to tolerate a certain number of node or disk failures by reconstructing the lost data using the remaining fragments. For example, if a system employs an erasure coding scheme that splits a 100MB file into 10 fragments, it might generate 2 additional fragments, resulting in 12 total fragments stored. If any 10 of those 12 fragments are available, the original 100MB file can still be fully reconstructed. This makes erasure coding particularly efficient for environments where data integrity is crucial, yet the cost of maintaining multiple copies of data is undesirable. In contrast, simple backup typically involves creating another full copy of the data, which increases storage usage significantly. Data archiving focuses on moving infrequently accessed data to cheaper storage options rather than actively protecting against failures. Data compression aims to reduce the size of data for storage but does not address redundancy or failure protection. Thus, erasure coding stands out as the preferred method for protecting against node or disk failures without necessitating multiple copies

Erasure coding is a method used to ensure data reliability and availability while minimizing storage overhead. It works by breaking down the original data into smaller fragments, generating additional redundant fragments through algorithms, and then storing these fragments across different nodes or disks. This technique allows the system to tolerate a certain number of node or disk failures by reconstructing the lost data using the remaining fragments.

For example, if a system employs an erasure coding scheme that splits a 100MB file into 10 fragments, it might generate 2 additional fragments, resulting in 12 total fragments stored. If any 10 of those 12 fragments are available, the original 100MB file can still be fully reconstructed. This makes erasure coding particularly efficient for environments where data integrity is crucial, yet the cost of maintaining multiple copies of data is undesirable.

In contrast, simple backup typically involves creating another full copy of the data, which increases storage usage significantly. Data archiving focuses on moving infrequently accessed data to cheaper storage options rather than actively protecting against failures. Data compression aims to reduce the size of data for storage but does not address redundancy or failure protection. Thus, erasure coding stands out as the preferred method for protecting against node or disk failures without necessitating multiple copies