<s>
A	O
disk	B-General_Concept
array	I-General_Concept
is	O
a	O
disk	B-Device
storage	I-Device
system	O
which	O
contains	O
multiple	O
disk	B-Device
drives	I-Device
.	O
</s>
<s>
It	O
is	O
differentiated	O
from	O
a	O
disk	B-Device
enclosure	I-Device
,	O
in	O
that	O
an	O
array	O
has	O
cache	B-General_Concept
memory	I-General_Concept
and	O
advanced	O
functionality	O
,	O
like	O
RAID	B-Architecture
,	O
deduplication	B-General_Concept
,	O
encryption	O
and	O
virtualization	B-Application
.	O
</s>
<s>
Components	O
of	O
a	O
disk	B-General_Concept
array	I-General_Concept
include	O
:	O
</s>
<s>
Cache	B-General_Concept
in	O
form	O
of	O
both	O
volatile	O
random-access	B-Architecture
memory	I-Architecture
and	O
non-volatile	B-General_Concept
flash	B-Device
memory	I-Device
.	O
</s>
<s>
Disk	B-Device
enclosures	I-Device
for	O
both	O
magnetic	B-Architecture
rotational	O
hard	B-Device
disk	I-Device
drives	I-Device
and	O
electronic	O
solid-state	B-Device
drives	I-Device
.	O
</s>
<s>
Typically	O
a	O
disk	B-General_Concept
array	I-General_Concept
provides	O
increased	O
availability	O
,	O
resiliency	O
,	O
and	O
maintainability	O
by	O
using	O
additional	O
redundant	O
components	O
(	O
controllers	O
,	O
power	O
supplies	O
,	O
fans	O
,	O
etc	O
.	O
</s>
<s>
)	O
,	O
often	O
up	O
to	O
the	O
point	O
where	O
all	O
single	B-Architecture
points	I-Architecture
of	I-Architecture
failure	I-Architecture
(	O
SPOFs	B-Architecture
)	O
are	O
eliminated	O
from	O
the	O
design	O
.	O
</s>
<s>
Additionally	O
,	O
disk	B-General_Concept
array	I-General_Concept
components	O
are	O
often	O
hot-swappable	B-Device
.	O
</s>
<s>
Traditionally	O
disk	B-General_Concept
arrays	I-General_Concept
were	O
divided	O
into	O
categories	O
:	O
</s>
<s>
Primary	O
vendors	O
of	O
storage	O
systems	O
include	O
Coraid	O
,	O
Inc.	O
,	O
DataDirect	O
Networks	O
,	O
Dell	O
EMC	O
,	O
Fujitsu	O
,	O
Hewlett	O
Packard	O
Enterprise	O
,	O
Hitachi	O
Data	O
Systems	O
,	O
Huawei	O
,	O
IBM	O
,	O
Infortrend	O
,	O
NetApp	O
,	O
Oracle	B-Application
Corporation	I-Application
,	O
Panasas	O
,	O
Pure	B-General_Concept
Storage	I-General_Concept
and	O
other	O
companies	O
that	O
often	O
act	O
as	O
OEM	O
for	O
the	O
above	O
vendors	O
and	O
do	O
not	O
themselves	O
market	O
the	O
storage	O
components	O
they	O
manufacture	O
.	O
</s>
