<s>
The	O
Open	B-General_Concept
Cloud	I-General_Concept
Computing	I-General_Concept
Interface	I-General_Concept
(	O
OCCI	O
)	O
is	O
a	O
set	O
of	O
specifications	O
delivered	O
through	O
the	O
Open	O
Grid	O
Forum	O
,	O
for	O
cloud	B-Architecture
computing	I-Architecture
service	O
providers	O
.	O
</s>
<s>
It	O
builds	O
upon	O
World	O
Wide	O
Web	O
fundamentals	O
by	O
using	O
the	O
Representational	B-Protocol
State	I-Protocol
Transfer	I-Protocol
(	O
REST	O
)	O
approach	O
for	O
interacting	O
with	O
services	O
.	O
</s>
<s>
The	O
aim	O
of	O
the	O
Open	B-General_Concept
Cloud	I-General_Concept
Computing	I-General_Concept
Interface	I-General_Concept
is	O
the	O
development	O
of	O
an	O
open	O
specification	O
and	O
API	O
for	O
cloud	O
offerings	O
.	O
</s>
<s>
IaaS	O
is	O
one	O
of	O
three	O
primary	O
segments	O
of	O
the	O
cloud	B-Architecture
computing	I-Architecture
industry	O
in	O
which	O
compute	O
,	O
storage	O
and	O
network	O
resources	O
are	O
provided	O
as	O
services	O
.	O
</s>
<s>
It	O
covers	O
management	O
of	O
the	O
entire	O
life-cycle	O
of	O
OCCI-defined	O
model	O
entities	O
and	O
is	O
compatible	O
with	O
existing	O
standards	O
such	O
as	O
the	O
Open	O
Virtualization	O
Format	O
(	O
OVF	O
)	O
and	O
the	O
Cloud	B-General_Concept
Data	I-General_Concept
Management	I-General_Concept
Interface	I-General_Concept
(	O
CDMI	B-General_Concept
)	O
.	O
</s>
<s>
OCCI	O
began	O
in	O
March	O
2009	O
and	O
was	O
initially	O
led	O
by	O
RabbitMQ	B-Application
and	O
the	O
Complutense	O
University	O
of	O
Madrid	O
.	O
</s>
<s>
Project	O
Link	O
European	O
Grid	O
Infrastructure	O
OCCI	O
used	O
in	O
its	O
multi-organization	O
community	O
Federated	O
Cloud	O
OpenNebula	B-Language
Supports	O
OCCI	O
,	O
Amazon	B-Application
Web	I-Application
Services	I-Application
and	O
its	O
internal	O
Sunstone	O
GUI	O
interfaces	O
.	O
</s>
<s>
Alternative	O
approaches	O
include	O
the	O
use	O
of	O
the	O
Cloud	B-General_Concept
Infrastructure	I-General_Concept
Management	I-General_Concept
Interface	I-General_Concept
(	O
CIMI	O
)	O
and	O
related	O
standards	O
set	O
from	O
DMTF	O
and	O
the	O
Amazon	B-Application
Web	I-Application
Services	I-Application
interfaces	O
from	O
Amazon	O
.	O
</s>
<s>
OpenNebula	B-Language
conducted	O
a	O
survey	O
of	O
their	O
users	O
in	O
which	O
the	O
results	O
showed	O
38%	O
do	O
not	O
expose	O
cloud	O
APIs	O
,	O
their	O
users	O
only	O
interface	O
through	O
the	O
Sunstone	O
GUI	O
,	O
36%	O
mostly	O
use	O
the	O
Amazon	B-Application
Web	I-Application
Services	I-Application
API	O
,	O
and	O
26%	O
mostly	O
use	O
the	O
OpenNebula	B-Language
’s	O
OCCI	O
API	O
or	O
the	O
OCCI	O
API	O
offered	O
by	O
rOCCI	O
.	O
</s>
