1. Cloud Computing Vs RAID Group 21 Fangfei Li John Soh Course: CSCI4707

2. Introduction What are the important traits of a data storage technology? Reliability: Backup of details - if data gets destroyed, still have backup. Security: Data protection from hackers. Speed: Back things up fast.

3. What is RAID? Data storage technology that combines multiple disk drives into a single logical unit. History of RAID: Invented by David Patterson, Garth A.Gibson, and Randy Katz at University of California, Berkeley. How is data stored in RAID? Distributed across drives in a particular way called RAID levels. Different RAID levels provides different balance among -’reliability, availability, performance, and capacity’.

4. Various RAID levels

5. RAID Terminology Striping: Segmenting logically sequential data so that consecutive segments are stored on different physical storage devices Mirroring: Replication of logical disk into a separate hard disk. Parity bit: Bit added to end of a string to check number of bits is even or odd. Hamming code: Algorithm for single-bit error detection and correction.

6. What is Cloud Computing? The idea of Cloud Computing began in 1960s Cloud Computing - data is stored on remote servers accessed through internet. It’s underlying hardware are disk arrays.

7. Cloud Storage - Erasure Coding Encodes k size data transmitted in n parts Allows the original data to be derived from a subset of n parts Somewhat math heavy - erasure coding can present computational overhead in large - scale data sets, the efficiency that erasure coding brings outweighs the computational overhead.

8. Comparing Cloud and RAID Fault tolerance: some big tech companies uses software rather than hardware for fault tolerance Price: RAID is more hardware intensive thus increasing the cost vs cloud storage. Speed: Cloud storage is dependent on software. Reliability

9. Who uses RAID? RAID is faster and more reliable. Basically any organization that requires speed and reliability over cost.

10. Who uses CLOUD? Cloud is cheap.

11. Will Cloud Storage replace RAID The needs are different for different companies. Stock companies need the data to be secure combined reliable retrieval. Companies like google, facebook are primarily concerned cost. So, the answer would be no.

12. https://www.techopedia.com/definition/26535/cloud-storage https://en.wikipedia.org/wiki/Standard_RAID_levels