Redundant Arrays of Independent Disks

storage, architecture (RAID. Originally "Redundant Arrays

of Inexpensive Disks") A project at the computer science

department of the University of California at Berkeley,

under the direction of Professor Katz, in conjunction with

Professor John Ousterhout and Professor David Patterson.

The project is reaching its culmination with the

implementation of a prototype disk array file server with a

capacity of 40 GBytes and a sustained bandwidth of 80

MBytes/second. The server is being interfaced to a 1 Gb/s

local area network. A new initiative, which is part of the

Sequoia 2000 Project, seeks to construct a geographically

distributed storage system spanning disk arrays and automated

libraries of optical disks and tapes. The project will

extend the interleaved storage techniques so successfully

applied to disks to tertiary storage devices. A key element

of the research will be to develop techniques for managing

latency in the I/O and network paths.

The original ("..Inexpensive..") term referred to the 3.5 and

5.25 inch disks used for the first RAID system but no longer

applies.

The following standard RAID specifications exist:

RAID 0 Non-redundant striped array

RAID 1 Mirrored arrays

RAID 2 Parallel array with ECC

RAID 3 Parallel array with parity

RAID 4 Striped array with parity

RAID 5 Striped array with rotating parity

.

.

["A Case for Redundant Arrays of Inexpensive Disks (RAID)",

"D. A. Patterson and G. Gibson and R. H. Katz", Proc ACM

SIGMOD Conf, Chicago, IL, Jun 1988].

["Introduction to Redundant Arrays of Inexpensive Disks

(RAID)", "D. A. Patterson and P. Chen and G. Gibson and

R. H. Katz", IEEE COMPCON 89, San Francisco, Feb-Mar 1989].

(1995-07-20)