<s>
ATA	B-Protocol
over	I-Protocol
Ethernet	I-Protocol
(	O
AoE	O
)	O
is	O
a	O
network	O
protocol	O
developed	O
by	O
the	O
Brantley	O
Coile	O
Company	O
,	O
designed	O
for	O
simple	O
,	O
high-performance	O
access	O
of	O
block	B-General_Concept
storage	I-General_Concept
devices	O
over	O
Ethernet	O
networks	O
.	O
</s>
<s>
AoE	O
runs	O
on	O
layer	B-Protocol
2	I-Protocol
Ethernet	O
.	O
</s>
<s>
AoE	O
does	O
not	O
use	O
Internet	B-Protocol
Protocol	I-Protocol
(	O
IP	O
)	O
;	O
it	O
cannot	O
be	O
accessed	O
over	O
the	O
Internet	O
or	O
other	O
IP	O
networks	O
.	O
</s>
<s>
In	O
this	O
regard	O
it	O
is	O
more	O
comparable	O
to	O
Fibre	B-Protocol
Channel	I-Protocol
over	I-Protocol
Ethernet	I-Protocol
than	O
iSCSI	B-Protocol
.	O
</s>
<s>
The	O
AoE	O
specification	O
is	O
12	O
pages	O
compared	O
with	O
iSCSI	B-Protocol
's	O
257	O
pages	O
.	O
</s>
<s>
AoE	O
has	O
the	O
IEEE	O
assigned	O
EtherType	B-Protocol
0x88A2	O
.	O
</s>
<s>
SATA	O
(	O
and	O
older	O
PATA	B-Protocol
)	O
hard	O
drives	O
use	O
the	O
Advanced	B-Protocol
Technology	I-Protocol
Attachment	I-Protocol
(	O
ATA	O
)	O
protocol	O
to	O
issue	O
commands	O
,	O
such	O
as	O
read	O
,	O
write	O
,	O
and	O
status	O
.	O
</s>
<s>
Although	O
internally	O
AoE	O
uses	O
the	O
ATA	O
protocol	O
,	O
it	O
presents	O
the	O
disks	O
as	O
SCSI	O
to	O
the	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
Also	O
the	O
actual	O
disks	O
can	O
be	O
SCSI	O
or	O
any	O
other	O
kind	O
,	O
AoE	O
is	O
not	O
limited	O
to	O
disks	O
that	O
use	O
the	O
ATA	B-Protocol
command	I-Protocol
set	I-Protocol
.	O
</s>
<s>
By	O
using	O
an	O
AoE	O
driver	O
,	O
the	O
host	O
operating	B-General_Concept
system	I-General_Concept
is	O
able	O
to	O
access	O
a	O
remote	O
disk	O
as	O
if	O
it	O
were	O
directly	O
attached	O
.	O
</s>
<s>
AoE	O
is	O
a	O
layer	B-Protocol
2	I-Protocol
protocol	O
running	O
at	O
the	O
data-link	B-Protocol
layer	I-Protocol
,	O
unlike	O
some	O
other	O
SAN	O
protocols	O
which	O
run	O
on	O
top	O
of	O
layer	O
3	O
utilizing	O
IP	O
.	O
</s>
<s>
Instead	O
,	O
AoE	O
packets	O
can	O
only	O
travel	O
within	O
a	O
single	O
local	O
Ethernet	O
storage	O
area	O
network	O
(	O
e.g.	O
,	O
a	O
set	O
of	O
computers	O
connected	O
to	O
the	O
same	O
switch	O
or	O
in	O
the	O
same	O
LAN	O
Subnet	O
or	O
VLAN	B-General_Concept
)	O
.	O
</s>
<s>
Most	O
secure	O
AoE	O
by	O
using	O
Ethernet	O
VLANs	B-General_Concept
.	O
</s>
<s>
Without	O
this	O
cooperation	O
file-system	O
corruption	O
and	O
data	O
loss	O
is	O
likely	O
,	O
unless	O
access	O
is	O
strictly	O
read-only	O
or	O
a	O
cluster	B-Application
file	I-Application
system	I-Application
is	O
used	O
.	O
</s>
<s>
The	O
following	O
operating	B-General_Concept
systems	I-General_Concept
provide	O
ATA	B-Protocol
over	I-Protocol
Ethernet	I-Protocol
(	O
AoE	O
)	O
support	O
:	O
</s>
<s>
OS	O
Support	O
Third-party	O
drivers	O
Linux	B-Operating_System
Native	O
(	O
2.6.11	O
+	O
)	O
Coraid	O
Windows	B-Application
Third-party	O
StarWind	O
Software	O
AoE	O
Initiator	O
,	O
StarWind	O
Free	O
AoE	O
Initiator	O
for	O
Microsoft	B-Application
Windows	I-Application
WinAoE	O
,	O
WinAoE	O
Driver	O
:	O
A	O
bootable	O
,	O
open	O
source	O
AoE	O
initiator	O
,	O
EOL-ed	O
and	O
phased	O
out	O
by	O
WinVBlock	O
successor	O
WinVBlock	O
WinVBlock	O
Driver	O
:	O
A	O
WinAoE	O
fork	O
capable	O
of	O
booting	O
AoE	O
targets	O
,	O
file-backed	O
disks	O
and	O
RAM	O
disks	O
created	O
with	O
MEMDISK	O
and	O
GRUB4DOS	O
Mac	O
OS	O
X	O
10.4	O
and	O
up	O
Third-party	O
From	O
2006	O
through	O
2010	O
,	O
2ºFrost	O
Technologies	O
developed	O
proprietary	O
software	O
and	O
marketed	O
AoE	O
storage	O
solutions	O
in	O
the	O
Windows	B-Application
and	O
Mac	O
markets	O
.	O
</s>
<s>
The	O
Mac	O
implementation	O
was	O
its	O
own	O
and	O
the	O
Windows	B-Application
version	O
was	O
OEM-ed	O
from	O
StarWind	O
Software	O
.	O
</s>
<s>
Coraid	O
offered	O
an	O
array	O
of	O
AoE	O
SAN	O
appliances	O
under	O
the	O
EtherDrive	O
brand	O
,	O
along	O
with	O
diskless	O
gateways	O
that	O
add	O
network-attached	B-Application
storage	I-Application
functionality	O
,	O
using	O
the	O
NFS	B-Protocol
or	O
SMB	B-Operating_System
protocols	I-Operating_System
,	O
to	O
one	O
or	O
more	O
AoE	O
appliances	O
.	O
</s>
<s>
Traditional	O
filesystems	O
(	O
such	O
as	O
FAT	B-Application
or	O
ext3	B-Application
)	O
are	O
designed	O
to	O
be	O
accessed	O
by	O
a	O
single	O
host	O
,	O
and	O
will	O
cause	O
unpredictable	O
behavior	O
if	O
accessed	O
by	O
multiple	O
machines	O
.	O
</s>
