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All Posts Tagged Tag: ‘protection’

The Data Protection Diaries Part 3 – Parity RAID

Raid 3

In this installment of As the Disk Drive Turns, we’ll explore RAID levels two through five and the math(s) they use to protect data with less overhead than mirroring. RAID2 and RAID3 Bits and Bytes Not Blocks RAID2 stripes data across multiple drives at the bit level using Hamming codes. RAID3 uses parity but at the byte, not block level. …

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All About Data Protection – Part 2 How RAID Works Stripes and Mirrors

Mirror

Here’s how storage systems use the concepts of RAID to protect your data. In A Case for Redundant Arrays of Inexpensive Disks, Patterson, Gibson and Katz propose five methods for using arrays of slow, unreliable but inexpensive drives to match the performance and reliability of the SLEDs (Single Large Expensive Disks) then dominating the minicomputer and mainframe storage market. They …

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All About Data Protection – Part One Where Did RAID Come From?

RAID

Just about all modern data protection schemes divide data into some arbitrarily sized block. Then, they either duplicate that block across multiple storage devices, or store portions of that data block, which we’ll call strips, in stripes across multiple storage devices, with one or more additional strips in each stripe containing parity or other erasure code data. Those are pretty …

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