<s>
Cloud	B-Architecture
computing	I-Architecture
is	O
the	O
on-demand	B-Protocol
availability	O
of	O
computer	O
system	B-General_Concept
resources	I-General_Concept
,	O
especially	O
data	O
storage	O
(	O
cloud	O
storage	O
)	O
and	O
computing	O
power	O
,	O
without	O
direct	O
active	O
management	O
by	O
the	O
user	O
.	O
</s>
<s>
Large	O
clouds	O
often	O
have	O
functions	O
distributed	B-Architecture
over	O
multiple	O
locations	O
,	O
each	O
of	O
which	O
is	O
a	O
data	B-Operating_System
center	I-Operating_System
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
relies	O
on	O
sharing	O
of	O
resources	O
to	O
achieve	O
coherence	O
and	O
typically	O
uses	O
a	O
pay-as-you-go	O
model	O
,	O
which	O
can	O
help	O
in	O
reducing	O
capital	O
expenses	O
but	O
may	O
also	O
lead	O
to	O
unexpected	O
operating	O
expenses	O
for	O
users	O
.	O
</s>
<s>
Advocates	O
of	O
public	O
and	O
hybrid	O
clouds	O
claim	O
that	O
cloud	B-Architecture
computing	I-Architecture
allows	O
companies	O
to	O
avoid	O
or	O
minimize	O
up-front	O
IT	B-Application
infrastructure	I-Application
costs	O
.	O
</s>
<s>
Proponents	O
also	O
claim	O
that	O
cloud	B-Architecture
computing	I-Architecture
allows	O
enterprises	O
to	O
get	O
their	O
applications	B-Application
up	O
and	O
running	O
faster	O
,	O
with	O
improved	O
manageability	O
and	O
less	O
maintenance	O
,	O
and	O
that	O
it	B-General_Concept
enables	O
IT	B-General_Concept
teams	O
to	O
more	O
rapidly	O
adjust	O
resources	O
to	O
meet	O
fluctuating	O
and	O
unpredictable	O
demand	O
,	O
providing	O
burst	B-Architecture
computing	I-Architecture
capability	O
:	O
high	O
computing	O
power	O
at	O
certain	O
periods	O
of	O
peak	O
demand	O
.	O
</s>
<s>
According	O
to	O
International	O
Data	O
Corporation	O
(	O
IDC	O
)	O
,	O
global	O
spending	O
on	O
cloud	B-Architecture
computing	I-Architecture
services	O
has	O
reached	O
$706	O
billion	O
and	O
expected	O
to	O
reach	O
$1.3	O
trillion	O
by	O
2025	O
.	O
</s>
<s>
While	O
Gartner	O
estimated	O
that	O
global	O
public	O
cloud	B-Architecture
services	I-Architecture
end-user	O
spending	O
would	O
reach	O
$600	O
billion	O
by	O
2023	O
.	O
</s>
<s>
In	O
2022	O
,	O
more	O
than	O
$1.3	O
trillion	O
in	O
enterprise	O
IT	B-General_Concept
spending	O
was	O
at	O
stake	O
from	O
the	O
shift	O
to	O
the	O
cloud	O
,	O
growing	O
to	O
almost	O
$1.8	O
trillion	O
in	O
2025	O
,	O
according	O
to	O
Gartner	O
.	O
</s>
<s>
The	O
term	O
cloud	O
was	O
used	O
to	O
refer	O
to	O
platforms	B-Device
for	O
distributed	B-Architecture
computing	I-Architecture
as	O
early	O
as	O
1993	O
,	O
when	O
Apple	O
spin-off	O
General	O
Magic	O
and	O
AT&T	O
used	O
it	B-General_Concept
in	O
describing	O
their	O
(	O
paired	O
)	O
Telescript	B-Language
and	O
Personal	O
Link	O
technologies	O
.	O
</s>
<s>
In	O
Wired	O
's	O
April	O
1994	O
feature	O
"	O
Bill	O
and	O
Andy	O
's	O
Excellent	O
Adventure	O
II	O
"	O
,	O
Andy	O
Hertzfeld	O
commented	O
on	O
Telescript	B-Language
,	O
General	O
Magic	O
's	O
distributed	B-Architecture
programming	I-Architecture
language	O
:	O
</s>
<s>
During	O
the	O
1960s	O
,	O
the	O
initial	O
concepts	O
of	O
time-sharing	B-General_Concept
became	O
popularized	O
via	O
Remote	B-Protocol
Job	I-Protocol
Entry	I-Protocol
(	O
RJE	B-Protocol
)	O
;	O
this	O
terminology	O
was	O
mostly	O
associated	O
with	O
large	O
vendors	O
such	O
as	O
IBM	O
and	O
DEC	O
.	O
Full-time-sharing	O
solutions	O
were	O
available	O
by	O
the	O
early	O
1970s	O
on	O
such	O
platforms	B-Device
as	O
Multics	B-Application
(	O
on	O
GE	O
hardware	O
)	O
,	O
Cambridge	O
CTSS	O
,	O
and	O
the	O
earliest	O
UNIX	B-Application
ports	O
(	O
on	O
DEC	O
hardware	O
)	O
.	O
</s>
<s>
Yet	O
,	O
the	O
"	O
data	B-Operating_System
center	I-Operating_System
"	O
model	O
where	O
users	O
submitted	O
jobs	O
to	O
operators	O
to	O
run	O
on	O
IBM	O
mainframes	O
was	O
overwhelmingly	O
predominant	O
.	O
</s>
<s>
In	O
the	O
1990s	O
,	O
telecommunications	O
companies	O
,	O
who	O
previously	O
offered	O
primarily	O
dedicated	O
point-to-point	O
data	O
circuits	O
,	O
began	O
offering	O
virtual	B-Application
private	I-Application
network	I-Application
(	O
VPN	B-Application
)	O
services	O
with	O
comparable	O
quality	O
of	O
service	O
,	O
but	O
at	O
a	O
lower	O
cost	O
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
extended	O
this	O
boundary	O
to	O
cover	O
all	O
servers	O
as	O
well	O
as	O
the	O
network	B-Architecture
infrastructure	I-Architecture
.	O
</s>
<s>
As	O
computers	O
became	O
more	O
diffused	O
,	O
scientists	O
and	O
technologists	O
explored	O
ways	O
to	O
make	O
large-scale	O
computing	O
power	O
available	O
to	O
more	O
users	O
through	O
time-sharing	B-General_Concept
.	O
</s>
<s>
They	O
experimented	O
with	O
algorithms	O
to	O
optimize	O
the	O
infrastructure	O
,	O
platform	O
,	O
and	O
applications	B-Application
,	O
to	O
prioritize	O
tasks	O
to	O
be	O
executed	O
by	O
CPUs	B-General_Concept
,	O
and	O
to	O
increase	O
efficiency	O
for	O
end	O
users	O
.	O
</s>
<s>
The	O
use	O
of	O
the	O
cloud	O
metaphor	O
for	O
virtualized	B-General_Concept
services	O
dates	O
at	O
least	O
to	O
General	O
Magic	O
in	O
1994	O
,	O
where	O
it	B-General_Concept
was	O
used	O
to	O
describe	O
the	O
universe	O
of	O
"	O
places	O
"	O
that	O
mobile	B-Operating_System
agents	I-Operating_System
in	O
the	O
Telescript	B-Language
environment	O
could	O
go	O
.	O
</s>
<s>
In	O
addition	O
to	O
use	O
by	O
General	O
Magic	O
itself	O
,	O
it	B-General_Concept
was	O
also	O
used	O
in	O
promoting	O
T	O
's	O
associated	O
Personal	O
Link	O
Services	O
.	O
</s>
<s>
In	O
July	O
2002	O
,	O
Amazon	B-Application
created	O
the	O
subsidiary	O
Amazon	B-Application
Web	I-Application
Services	I-Application
,	O
to	O
"	O
enable	O
developers	O
to	O
build	O
innovative	O
and	O
entrepreneurial	O
applications	B-Application
on	O
their	O
own.	O
"	O
</s>
<s>
In	O
March	O
2006	O
Amazon	B-Application
introduced	O
its	O
Simple	B-General_Concept
Storage	I-General_Concept
Service	I-General_Concept
(	O
S3	O
)	O
,	O
followed	O
by	O
Elastic	B-General_Concept
Compute	I-General_Concept
Cloud	I-General_Concept
(	O
EC2	O
)	O
in	O
August	O
of	O
the	O
same	O
year	O
.	O
</s>
<s>
These	O
products	O
pioneered	O
the	O
usage	O
of	O
server	B-General_Concept
virtualization	I-General_Concept
to	O
deliver	O
IaaS	B-General_Concept
at	O
a	O
cheaper	O
and	O
on-demand	B-Protocol
pricing	O
basis	O
.	O
</s>
<s>
In	O
April	O
2008	O
,	O
Google	B-Application
released	O
the	O
beta	O
version	O
of	O
the	B-Application
Google	I-Application
App	B-Application
Engine	I-Application
.	O
</s>
<s>
The	O
App	B-Application
Engine	I-Application
was	O
a	O
PaaS	B-Application
(	O
one	O
of	O
the	O
first	O
of	O
its	O
kind	O
)	O
that	O
provided	O
a	O
fully	O
maintained	O
infrastructure	O
and	O
a	O
deployment	O
platform	O
for	O
users	O
to	O
create	O
web	B-Application
applications	I-Application
using	O
common	O
languages/technologies	O
such	O
as	O
Python	B-Language
,	O
Node.js	B-Language
,	O
and	O
PHP	B-Application
.	O
</s>
<s>
The	O
goal	O
was	O
to	O
eliminate	O
the	O
need	O
for	O
some	O
administrative	O
tasks	O
typical	O
of	O
an	O
IaaS	B-General_Concept
model	O
,	O
while	O
creating	O
a	O
platform	O
where	O
users	O
could	O
easily	O
deploy	O
such	O
applications	B-Application
and	O
scale	B-Architecture
them	O
to	O
demand	O
.	O
</s>
<s>
In	O
early	O
2008	O
,	O
NASA	O
's	O
Nebula	B-General_Concept
,	O
enhanced	O
in	O
the	O
RESERVOIR	O
European	O
Commission-funded	O
project	O
,	O
became	O
the	O
first	O
open-source	B-Application
software	I-Application
for	O
deploying	O
private	O
and	O
hybrid	O
clouds	O
,	O
and	O
for	O
the	O
federation	O
of	O
clouds	O
.	O
</s>
<s>
By	O
mid-2008	O
,	O
Gartner	O
saw	O
an	O
opportunity	O
for	O
cloud	B-Architecture
computing	I-Architecture
"	O
to	O
shape	O
the	O
relationship	O
among	O
consumers	O
of	O
IT	B-General_Concept
services	O
,	O
those	O
who	O
use	O
IT	B-General_Concept
services	O
and	O
those	O
who	O
sell	O
them	O
"	O
and	O
observed	O
that	O
"	O
organizations	O
are	O
switching	O
from	O
company-owned	O
hardware	O
and	O
software	B-General_Concept
assets	O
to	O
per-use	O
service-based	O
models	O
"	O
so	O
that	O
the	O
"	O
projected	O
shift	O
to	O
computing	O
...	O
will	O
result	O
in	O
dramatic	O
growth	O
in	O
IT	B-General_Concept
products	I-General_Concept
in	O
some	O
areas	O
and	O
significant	O
reductions	O
in	O
other	O
areas.	O
"	O
</s>
<s>
In	O
2008	O
,	O
the	O
U.S.	O
National	O
Science	O
Foundation	O
began	O
the	O
Cluster	B-Architecture
Exploratory	O
program	O
to	O
fund	O
academic	O
research	O
using	O
Google-IBM	O
cluster	B-Architecture
technology	O
to	O
analyze	O
massive	O
amounts	O
of	O
data	O
.	O
</s>
<s>
In	O
2009	O
,	O
the	O
government	O
of	O
France	O
announced	O
Project	O
Andromède	O
to	O
create	O
a	O
"	O
sovereign	O
cloud	O
"	O
or	O
national	O
cloud	B-Architecture
computing	I-Architecture
,	O
with	O
the	O
government	O
to	O
spend	O
€285	O
million	O
.	O
</s>
<s>
In	O
February	O
2010	O
,	O
Microsoft	O
released	O
Microsoft	B-Application
Azure	I-Application
,	O
which	O
had	O
been	O
announced	O
in	O
October	O
2008	O
.	O
</s>
<s>
In	O
July	O
2010	O
,	O
Rackspace	O
Hosting	O
and	O
NASA	O
jointly	O
launched	O
an	O
open-source	B-License
cloud-software	O
initiative	O
known	O
as	O
OpenStack	B-Application
.	O
</s>
<s>
The	O
OpenStack	B-Application
project	O
intended	O
to	O
help	O
organizations	O
offering	O
cloud-computing	B-Architecture
services	O
running	O
on	O
standard	O
hardware	O
.	O
</s>
<s>
The	O
early	O
code	O
came	O
from	O
NASA	O
's	O
Nebula	B-General_Concept
platform	I-General_Concept
as	O
well	O
as	O
from	O
Rackspace	O
's	O
Cloud	O
Files	O
platform	O
.	O
</s>
<s>
As	O
an	O
open-source	B-License
offering	O
and	O
along	O
with	O
other	O
open-source	B-License
solutions	O
such	O
as	O
CloudStack	O
,	O
Ganeti	O
,	O
and	O
OpenNebula	O
,	O
it	B-General_Concept
has	O
attracted	O
attention	O
by	O
several	O
key	O
communities	O
.	O
</s>
<s>
Several	O
studies	O
aim	O
at	O
comparing	O
these	O
open	B-License
source	I-License
offerings	O
based	O
on	O
a	O
set	O
of	O
criteria	O
.	O
</s>
<s>
On	O
March	O
1	O
,	O
2011	O
,	O
IBM	O
announced	O
the	O
IBM	B-General_Concept
SmartCloud	I-General_Concept
framework	O
to	O
support	O
Smarter	B-Device
Planet	I-Device
.	O
</s>
<s>
Among	O
the	O
various	O
components	O
of	O
the	O
Smarter	B-Device
Computing	I-Device
foundation	O
,	O
cloud	B-Architecture
computing	I-Architecture
is	O
a	O
critical	O
part	O
.	O
</s>
<s>
On	O
June	O
7	O
,	O
2012	O
,	O
Oracle	O
announced	O
the	O
Oracle	B-General_Concept
Cloud	I-General_Concept
.	O
</s>
<s>
In	O
2011	O
,	O
the	O
US	O
government	O
launched	O
the	O
Federal	O
Risk	O
Management	O
Program	O
,	O
FedRAMP	O
,	O
the	O
first	O
government-wide	O
cloud	B-Architecture
services	I-Architecture
accreditation	O
program	O
that	O
provides	O
standardized	O
risk	O
assessment	O
methodologies	O
for	O
cloud	O
products	O
and	O
services	O
.	O
</s>
<s>
In	O
May	O
2012	O
,	O
Google	B-General_Concept
Compute	I-General_Concept
Engine	I-General_Concept
was	O
released	O
in	O
preview	O
,	O
before	O
being	O
rolled	O
out	O
into	O
General	O
Availability	O
in	O
December	O
2013	O
.	O
</s>
<s>
In	O
2019	O
,	O
Linux	B-Operating_System
was	O
the	O
most	O
common	O
OS	O
used	O
on	O
Microsoft	B-Application
Azure	I-Application
.	O
</s>
<s>
In	O
December	O
2019	O
,	O
Amazon	B-Application
announced	O
AWS	B-Application
Outposts	O
,	O
which	O
is	O
a	O
fully	O
managed	O
service	O
that	O
extends	O
AWS	B-Application
infrastructure	O
,	O
AWS	B-Application
services	O
,	O
APIs	B-Application
,	O
and	O
tools	O
to	O
virtually	O
any	O
customer	O
datacenter	B-Operating_System
,	O
co-location	O
space	O
,	O
or	O
on-premises	B-General_Concept
facility	O
for	O
a	O
truly	O
consistent	O
hybrid	O
experience	O
.	O
</s>
<s>
The	O
goal	O
of	O
cloud	B-Architecture
computing	I-Architecture
is	O
to	O
allow	O
users	O
to	O
take	O
benefit	O
from	O
all	O
of	O
these	O
technologies	O
,	O
without	O
the	O
need	O
for	O
deep	O
knowledge	O
about	O
or	O
expertise	O
with	O
each	O
one	O
of	O
them	O
.	O
</s>
<s>
The	O
cloud	O
aims	O
to	O
cut	O
costs	O
and	O
helps	O
the	O
users	O
focus	O
on	O
their	O
core	O
business	O
instead	O
of	O
being	O
impeded	O
by	O
IT	B-General_Concept
obstacles	O
.	O
</s>
<s>
The	O
main	O
enabling	O
technology	O
for	O
cloud	B-Architecture
computing	I-Architecture
is	O
virtualization	B-General_Concept
.	O
</s>
<s>
Virtualization	B-General_Concept
software	B-General_Concept
separates	O
a	O
physical	O
computing	O
device	O
into	O
one	O
or	O
more	O
"	O
virtual	O
"	O
devices	O
,	O
each	O
of	O
which	O
can	O
be	O
easily	O
used	O
and	O
managed	O
to	O
perform	O
computing	O
tasks	O
.	O
</s>
<s>
With	O
operating	B-Application
system	I-Application
–	I-Application
level	I-Application
virtualization	I-Application
essentially	O
creating	O
a	O
scalable	B-Architecture
system	I-Architecture
of	O
multiple	O
independent	O
computing	O
devices	O
,	O
idle	O
computing	B-General_Concept
resources	I-General_Concept
can	O
be	O
allocated	O
and	O
used	O
more	O
efficiently	O
.	O
</s>
<s>
Virtualization	B-General_Concept
provides	O
the	O
agility	O
required	O
to	O
speed	O
up	O
IT	B-General_Concept
operations	O
and	O
reduces	O
cost	O
by	O
increasing	O
infrastructure	O
utilization	O
.	O
</s>
<s>
Autonomic	O
computing	O
automates	O
the	O
process	O
through	O
which	O
the	O
user	O
can	O
provision	O
resources	O
on-demand	B-Protocol
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
uses	O
concepts	O
from	O
utility	B-Operating_System
computing	I-Operating_System
to	O
provide	O
metrics	O
for	O
the	O
services	O
used	O
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
attempts	O
to	O
address	O
QoS	O
(	O
quality	O
of	O
service	O
)	O
and	O
reliability	B-Protocol
problems	O
of	O
other	O
grid	B-Architecture
computing	I-Architecture
models	O
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
shares	O
characteristics	O
with	O
:	O
</s>
<s>
Client	B-Operating_System
–	I-Operating_System
server	I-Operating_System
model	I-Operating_System
Client	B-Operating_System
–	I-Operating_System
server	I-Operating_System
computing	I-Operating_System
refers	O
broadly	O
to	O
any	O
distributed	B-Architecture
application	I-Architecture
that	O
distinguishes	O
between	O
service	O
providers	O
(	O
servers	O
)	O
and	O
service	O
requestors	O
(	O
clients	O
)	O
.	O
</s>
<s>
Computer	B-General_Concept
bureau	I-General_Concept
A	O
service	O
bureau	O
providing	O
computer	B-General_Concept
services	I-General_Concept
,	O
particularly	O
from	O
the	O
1960s	O
to	O
1980s	O
.	O
</s>
<s>
Grid	B-Architecture
computing	I-Architecture
A	O
form	O
of	O
distributed	B-Architecture
and	O
parallel	O
computing	O
,	O
whereby	O
a	O
'	O
super	O
and	O
virtual	B-Architecture
computer	I-Architecture
 '	O
is	O
composed	O
of	O
a	O
cluster	B-Architecture
of	O
networked	O
,	O
loosely	B-Application
coupled	I-Application
computers	O
acting	O
in	O
concert	O
to	O
perform	O
very	O
large	O
tasks	O
.	O
</s>
<s>
Fog	B-Device
computing	I-Device
Distributed	B-Architecture
computing	I-Architecture
paradigm	O
that	O
provides	O
data	O
,	O
compute	O
,	O
storage	O
and	O
application	O
services	O
closer	O
to	O
the	O
client	O
or	O
near-user	O
edge	B-Device
devices	I-Device
,	O
such	O
as	O
network	O
routers	O
.	O
</s>
<s>
Furthermore	O
,	O
fog	B-Device
computing	I-Device
handles	O
data	O
at	O
the	O
network	O
level	O
,	O
on	O
smart	O
devices	O
and	O
on	O
the	O
end-user	O
client-side	B-Operating_System
(	O
e.g.	O
</s>
<s>
Utility	B-Operating_System
computing	I-Operating_System
The	O
"	O
packaging	O
of	O
computing	B-General_Concept
resources	I-General_Concept
,	O
such	O
as	O
computation	O
and	O
storage	O
,	O
as	O
a	O
metered	O
service	O
similar	O
to	O
a	O
traditional	O
public	O
utility	O
,	O
such	O
as	O
electricity.	O
"	O
</s>
<s>
Peer-to-peer	O
A	O
distributed	B-Architecture
architecture	O
without	O
the	O
need	O
for	O
central	O
coordination	O
.	O
</s>
<s>
Participants	O
are	O
both	O
suppliers	O
and	O
consumers	O
of	O
resources	O
(	O
in	O
contrast	O
to	O
the	O
traditional	O
client-server	B-Operating_System
model	I-Operating_System
)	O
.	O
</s>
<s>
Cloud	O
sandbox	O
A	O
live	O
,	O
isolated	O
computer	O
environment	O
in	O
which	O
a	O
program	O
,	O
code	O
or	O
file	O
can	O
run	O
without	O
affecting	O
the	O
application	O
in	O
which	O
it	B-General_Concept
runs	O
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
exhibits	O
the	O
following	O
key	O
characteristics	O
:	O
</s>
<s>
Pricing	O
on	O
a	O
utility	B-Operating_System
computing	I-Operating_System
basis	O
is	O
"	O
fine-grained	O
"	O
,	O
with	O
usage-based	O
billing	O
options	O
.	O
</s>
<s>
As	O
well	O
,	O
less	O
in-house	B-Architecture
IT	B-General_Concept
skills	O
are	O
required	O
for	O
implementation	O
of	O
projects	O
that	O
use	O
cloud	B-Architecture
computing	I-Architecture
.	O
</s>
<s>
The	O
e-FISCAL	O
project	O
's	O
state-of-the-art	O
repository	O
contains	O
several	O
articles	O
looking	O
into	O
cost	O
aspects	O
in	O
more	O
detail	O
,	O
most	O
of	O
them	O
concluding	O
that	O
costs	O
savings	O
depend	O
on	O
the	O
type	O
of	O
activities	O
supported	O
and	O
the	O
type	O
of	O
infrastructure	O
available	O
in-house	B-Architecture
.	O
</s>
<s>
Device	B-Operating_System
and	I-Operating_System
location	I-Operating_System
independence	I-Operating_System
enable	O
users	O
to	O
access	O
systems	O
using	O
a	O
web	O
browser	O
regardless	O
of	O
their	O
location	O
or	O
what	O
device	O
they	O
use	O
(	O
e.g.	O
,	O
PC	O
,	O
mobile	O
phone	O
)	O
.	O
</s>
<s>
As	O
infrastructure	O
is	O
off-site	O
(	O
typically	O
provided	O
by	O
a	O
third-party	O
)	O
and	O
accessed	O
via	O
the	O
Internet	O
,	O
users	O
can	O
connect	O
to	O
it	B-General_Concept
from	O
anywhere	O
.	O
</s>
<s>
Maintenance	O
of	O
cloud	O
environment	O
is	O
easier	O
because	O
the	O
data	O
is	O
hosted	O
on	O
an	O
outside	O
server	O
maintained	O
by	O
a	O
provider	O
without	O
the	O
need	O
to	O
invest	O
in	O
data	B-Operating_System
center	I-Operating_System
hardware	O
.	O
</s>
<s>
IT	B-General_Concept
maintenance	O
of	O
cloud	B-Architecture
computing	I-Architecture
is	O
managed	O
and	O
updated	O
by	O
the	O
cloud	O
provider	O
's	O
IT	B-General_Concept
maintenance	O
team	O
which	O
reduces	O
cloud	B-Architecture
computing	I-Architecture
costs	O
compared	O
with	O
on-premises	B-General_Concept
data	B-Operating_System
centers	I-Operating_System
.	O
</s>
<s>
Multitenancy	B-Architecture
enables	O
sharing	O
of	O
resources	O
and	O
costs	O
across	O
a	O
large	O
pool	O
of	O
users	O
thus	O
allowing	O
for	O
:	O
</s>
<s>
Performance	B-General_Concept
is	O
monitored	O
by	O
IT	B-General_Concept
experts	O
from	O
the	O
service	O
provider	O
,	O
and	O
consistent	O
and	O
loosely	B-Application
coupled	I-Application
architectures	O
are	O
constructed	O
using	O
web	O
services	O
as	O
the	O
system	O
interface	O
.	O
</s>
<s>
Productivity	O
may	O
be	O
increased	O
when	O
multiple	O
users	O
can	O
work	O
on	O
the	O
same	O
data	O
simultaneously	O
,	O
rather	O
than	O
waiting	O
for	O
it	B-General_Concept
to	O
be	O
saved	O
and	O
emailed	O
.	O
</s>
<s>
Time	O
may	O
be	O
saved	O
as	O
information	O
does	O
not	O
need	O
to	O
be	O
re-entered	O
when	O
fields	O
are	O
matched	O
,	O
nor	O
do	O
users	O
need	O
to	O
install	O
application	B-Application
software	I-Application
upgrades	O
to	O
their	O
computer	O
.	O
</s>
<s>
Availability	O
improves	O
with	O
the	O
use	O
of	O
multiple	O
redundant	O
sites	O
,	O
which	O
makes	O
well-designed	O
cloud	B-Architecture
computing	I-Architecture
suitable	O
for	O
business	O
continuity	O
and	O
disaster	B-General_Concept
recovery	I-General_Concept
.	O
</s>
<s>
Scalability	B-Architecture
and	O
elasticity	B-General_Concept
via	O
dynamic	O
(	O
"	O
on-demand	B-Protocol
"	O
)	O
provisioning	O
of	O
resources	O
on	O
a	O
fine-grained	O
,	O
self-service	O
basis	O
in	O
near	O
real-time	O
(	O
Note	O
,	O
the	O
VM	O
startup	O
time	O
varies	O
by	O
VM	O
type	O
,	O
location	O
,	O
OS	O
and	O
cloud	O
providers	O
)	O
,	O
without	O
users	O
having	O
to	O
engineer	O
for	O
peak	O
loads	O
.	O
</s>
<s>
This	O
gives	O
the	O
ability	O
to	O
scale	B-Architecture
up	O
when	O
the	O
usage	O
need	O
increases	O
or	O
down	O
if	O
resources	O
are	O
not	O
being	O
used	O
.	O
</s>
<s>
The	O
time-efficient	O
benefit	O
of	O
cloud	O
scalability	B-Architecture
also	O
means	O
faster	O
time	O
to	O
market	O
,	O
more	O
business	O
flexibility	O
,	O
and	O
adaptability	O
,	O
as	O
adding	O
new	O
resources	O
does	O
not	O
take	O
as	O
much	O
time	O
as	O
it	B-General_Concept
used	O
to	O
.	O
</s>
<s>
Emerging	O
approaches	O
for	O
managing	O
elasticity	B-General_Concept
include	O
the	O
use	O
of	O
machine	O
learning	O
techniques	O
to	O
propose	O
efficient	O
elasticity	B-General_Concept
models	O
.	O
</s>
<s>
Security	O
can	O
improve	O
due	O
to	O
centralization	O
of	O
data	O
,	O
increased	O
security-focused	O
resources	O
,	O
etc.	O
,	O
but	O
concerns	O
can	O
persist	O
about	O
loss	O
of	O
control	O
over	O
certain	O
sensitive	O
data	O
,	O
and	O
the	O
lack	O
of	O
security	O
for	O
stored	O
kernels	B-Operating_System
.	O
</s>
<s>
However	O
,	O
the	O
complexity	O
of	O
security	O
is	O
greatly	O
increased	O
when	O
data	O
is	O
distributed	B-Architecture
over	O
a	O
wider	O
area	O
or	O
over	O
a	O
greater	O
number	O
of	O
devices	O
,	O
as	O
well	O
as	O
in	O
multi-tenant	B-Architecture
systems	O
shared	O
by	O
unrelated	O
users	O
.	O
</s>
<s>
The	O
National	O
Institute	O
of	O
Standards	O
and	O
Technology	O
's	O
definition	O
of	O
cloud	B-Architecture
computing	I-Architecture
identifies	O
"	O
five	O
essential	O
characteristics	O
"	O
:	O
</s>
<s>
Though	O
service-oriented	O
architecture	O
advocates	O
"	O
Everything	O
as	O
a	O
service	O
"	O
(	O
with	O
the	O
acronyms	O
EaaS	O
or	O
XaaS	O
,	O
or	O
simply	O
aas	O
)	O
,	O
cloud-computing	B-Architecture
providers	O
offer	O
their	O
"	O
services	O
"	O
according	O
to	O
different	O
models	O
,	O
of	O
which	O
the	O
three	O
standard	O
models	O
per	O
NIST	O
are	O
Infrastructure	B-General_Concept
as	I-General_Concept
a	I-General_Concept
Service	I-General_Concept
(	O
IaaS	B-General_Concept
)	O
,	O
Platform	B-Application
as	I-Application
a	I-Application
Service	I-Application
(	O
PaaS	B-Application
)	O
,	O
and	O
Software	B-Architecture
as	I-Architecture
a	I-Architecture
Service	I-Architecture
(	O
SaaS	B-Architecture
)	O
.	O
</s>
<s>
These	O
models	O
offer	O
increasing	O
abstraction	B-Application
;	O
they	O
are	O
thus	O
often	O
portrayed	O
as	O
layers	O
in	O
a	O
stack	B-Application
:	O
infrastructure-	O
,	O
platform	O
-	O
and	O
software-as-a-service	B-Architecture
,	O
but	O
these	O
need	O
not	O
be	O
related	O
.	O
</s>
<s>
For	O
example	O
,	O
one	O
can	O
provide	O
SaaS	B-Architecture
implemented	O
on	O
physical	O
machines	O
(	O
bare	O
metal	O
)	O
,	O
without	O
using	O
underlying	O
PaaS	B-Application
or	O
IaaS	B-General_Concept
layers	O
,	O
and	O
conversely	O
one	O
can	O
run	O
a	O
program	O
on	O
IaaS	B-General_Concept
and	O
access	O
it	B-General_Concept
directly	O
,	O
without	O
wrapping	O
it	B-General_Concept
as	O
SaaS	B-Architecture
.	O
</s>
<s>
"	O
Infrastructure	B-General_Concept
as	I-General_Concept
a	I-General_Concept
service	I-General_Concept
"	O
(	O
IaaS	B-General_Concept
)	O
refers	O
to	O
online	O
services	O
that	O
provide	O
high-level	O
APIs	B-Application
used	O
to	O
abstract	B-Application
various	O
low-level	O
details	O
of	O
underlying	O
network	B-Architecture
infrastructure	I-Architecture
like	O
physical	O
computing	B-General_Concept
resources	I-General_Concept
,	O
location	O
,	O
data	O
partitioning	O
,	O
scaling	B-Architecture
,	O
security	O
,	O
backup	O
,	O
etc	O
.	O
</s>
<s>
A	O
hypervisor	B-Operating_System
runs	O
the	O
virtual	B-Architecture
machines	I-Architecture
as	O
guests	O
.	O
</s>
<s>
Pools	O
of	O
hypervisors	B-Operating_System
within	O
the	O
cloud	O
operational	O
system	O
can	O
support	O
large	O
numbers	O
of	O
virtual	B-Architecture
machines	I-Architecture
and	O
the	O
ability	O
to	O
scale	B-Architecture
services	O
up	O
and	O
down	O
according	O
to	O
customers	O
 '	O
varying	O
requirements	O
.	O
</s>
<s>
Linux	B-Operating_System
containers	B-Application
run	O
in	O
isolated	O
partitions	O
of	O
a	O
single	O
Linux	B-Operating_System
kernel	I-Operating_System
running	O
directly	O
on	O
the	O
physical	O
hardware	O
.	O
</s>
<s>
Linux	B-Operating_System
cgroups	B-Application
and	O
namespaces	O
are	O
the	O
underlying	O
Linux	B-Operating_System
kernel	I-Operating_System
technologies	O
used	O
to	O
isolate	O
,	O
secure	O
and	O
manage	O
the	O
containers	B-Application
.	O
</s>
<s>
Containerisation	O
offers	O
higher	O
performance	B-General_Concept
than	O
virtualization	B-General_Concept
because	O
there	O
is	O
no	O
hypervisor	B-Operating_System
overhead	O
.	O
</s>
<s>
IaaS	B-General_Concept
clouds	O
often	O
offer	O
additional	O
resources	O
such	O
as	O
a	O
virtual-machine	O
disk-image	B-Application
library	O
,	O
raw	O
block	B-General_Concept
storage	I-General_Concept
,	O
file	O
or	O
object	B-Application
storage	I-Application
,	O
firewalls	O
,	O
load	B-Application
balancers	I-Application
,	O
IP	B-Protocol
addresses	I-Protocol
,	O
virtual	B-General_Concept
local	I-General_Concept
area	I-General_Concept
networks	I-General_Concept
(	O
VLANs	B-General_Concept
)	O
,	O
and	O
software	B-General_Concept
bundles	O
.	O
</s>
<s>
The	O
NIST	O
's	O
definition	O
of	O
cloud	B-Architecture
computing	I-Architecture
describes	O
IaaS	B-General_Concept
as	O
"	O
where	O
the	O
consumer	O
is	O
able	O
to	O
deploy	O
and	O
run	O
arbitrary	O
software	B-General_Concept
,	O
which	O
can	O
include	O
operating	O
systems	O
and	O
applications	B-Application
.	O
</s>
<s>
The	O
consumer	O
does	O
not	O
manage	O
or	O
control	O
the	O
underlying	O
cloud	O
infrastructure	O
but	O
has	O
control	O
over	O
operating	O
systems	O
,	O
storage	O
,	O
and	O
deployed	O
applications	B-Application
;	O
and	O
possibly	O
limited	O
control	O
of	O
select	O
networking	O
components	O
(	O
e.g.	O
,	O
host	O
firewalls	O
)	O
.	O
"	O
</s>
<s>
IaaS-cloud	O
providers	O
supply	O
these	O
resources	O
on-demand	B-Protocol
from	O
their	O
large	O
pools	O
of	O
equipment	O
installed	O
in	O
data	B-Operating_System
centers	I-Operating_System
.	O
</s>
<s>
For	O
wide-area	O
connectivity	O
,	O
customers	O
can	O
use	O
either	O
the	O
Internet	O
or	O
carrier	B-General_Concept
clouds	I-General_Concept
(	O
dedicated	O
virtual	B-Application
private	I-Application
networks	I-Application
)	O
.	O
</s>
<s>
To	O
deploy	O
their	O
applications	B-Application
,	O
cloud	B-Architecture
users	I-Architecture
install	O
operating-system	O
images	O
and	O
their	O
application	B-Application
software	I-Application
on	O
the	O
cloud	O
infrastructure	O
.	O
</s>
<s>
In	O
this	O
model	O
,	O
the	O
cloud	O
user	O
patches	O
and	O
maintains	O
the	O
operating	O
systems	O
and	O
the	O
application	B-Application
software	I-Application
.	O
</s>
<s>
Cloud	O
providers	O
typically	O
bill	O
IaaS	B-General_Concept
services	O
on	O
a	O
utility	B-Operating_System
computing	I-Operating_System
basis	O
:	O
cost	O
reflects	O
the	O
number	O
of	O
resources	O
allocated	O
and	O
consumed	O
.	O
</s>
<s>
The	O
NIST	O
's	O
definition	O
of	O
cloud	B-Architecture
computing	I-Architecture
defines	O
Platform	B-Application
as	I-Application
a	I-Application
Service	I-Application
as	O
:	O
</s>
<s>
PaaS	B-Application
vendors	O
offer	O
a	O
development	O
environment	O
to	O
application	O
developers	O
.	O
</s>
<s>
In	O
the	O
PaaS	B-Application
models	O
,	O
cloud	O
providers	O
deliver	O
a	O
computing	B-Device
platform	I-Device
,	O
typically	O
including	O
an	O
operating	O
system	O
,	O
programming-language	O
execution	B-General_Concept
environment	O
,	O
database	O
,	O
and	O
the	O
web	O
server	O
.	O
</s>
<s>
Application	O
developers	O
develop	O
and	O
run	O
their	O
software	B-General_Concept
on	O
a	O
cloud	O
platform	O
instead	O
of	O
directly	O
buying	O
and	O
managing	O
the	O
underlying	O
hardware	O
and	O
software	B-General_Concept
layers	O
.	O
</s>
<s>
With	O
some	O
PaaS	B-Application
,	O
the	O
underlying	O
computer	O
and	O
storage	O
resources	O
scale	B-Architecture
automatically	O
to	O
match	O
application	O
demand	O
so	O
that	O
the	O
cloud	O
user	O
does	O
not	O
have	O
to	O
allocate	O
resources	O
manually	O
.	O
</s>
<s>
Some	O
integration	O
and	O
data	O
management	O
providers	O
also	O
use	O
specialized	O
applications	B-Application
of	O
PaaS	B-Application
as	O
delivery	O
models	O
for	O
data	O
.	O
</s>
<s>
Examples	O
include	O
iPaaS	O
(	O
Integration	O
Platform	B-Application
as	I-Application
a	I-Application
Service	I-Application
)	O
and	O
dPaaS	O
(	O
Data	O
Platform	B-Application
as	I-Application
a	I-Application
Service	I-Application
)	O
.	O
</s>
<s>
Under	O
the	O
dPaaS	O
model	O
,	O
the	O
PaaS	B-Application
provider	O
,	O
not	O
the	O
customer	O
,	O
manages	O
the	O
development	O
and	O
execution	B-General_Concept
of	O
programs	O
by	O
building	O
data	O
applications	B-Application
for	O
the	O
customer	O
.	O
</s>
<s>
dPaaS	O
users	O
access	O
data	O
through	O
data-visualization	B-Application
tools	O
.	O
</s>
<s>
The	O
NIST	O
's	O
definition	O
of	O
cloud	B-Architecture
computing	I-Architecture
defines	O
Software	B-Architecture
as	I-Architecture
a	I-Architecture
Service	I-Architecture
as	O
:	O
</s>
<s>
In	O
the	O
software	B-Architecture
as	I-Architecture
a	I-Architecture
service	I-Architecture
(	O
SaaS	B-Architecture
)	O
model	O
,	O
users	O
gain	O
access	O
to	O
application	B-Application
software	I-Application
and	O
databases	B-Application
.	O
</s>
<s>
Cloud	O
providers	O
manage	O
the	O
infrastructure	O
and	O
platforms	B-Device
that	O
run	O
the	O
applications	B-Application
.	O
</s>
<s>
SaaS	B-Architecture
is	O
sometimes	O
referred	O
to	O
as	O
"	O
on-demand	B-Architecture
software	I-Architecture
"	O
and	O
is	O
usually	O
priced	O
on	O
a	O
pay-per-use	O
basis	O
or	O
using	O
a	O
subscription	O
fee	O
.	O
</s>
<s>
In	O
the	O
SaaS	B-Architecture
model	O
,	O
cloud	O
providers	O
install	O
and	O
operate	O
application	B-Application
software	I-Application
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
and	O
cloud	B-Architecture
users	I-Architecture
access	O
the	O
software	B-General_Concept
from	O
cloud	O
clients	O
.	O
</s>
<s>
Cloud	B-Architecture
users	I-Architecture
do	O
not	O
manage	O
the	O
cloud	O
infrastructure	O
and	O
platform	O
where	O
the	O
application	O
runs	O
.	O
</s>
<s>
Cloud	B-Architecture
applications	I-Architecture
differ	O
from	O
other	O
applications	B-Application
in	O
their	O
scalability	B-Architecture
—	O
which	O
can	O
be	O
achieved	O
by	O
cloning	O
tasks	O
onto	O
multiple	O
virtual	B-Architecture
machines	I-Architecture
at	O
run-time	O
to	O
meet	O
changing	O
work	O
demand	O
.	O
</s>
<s>
Load	B-Application
balancers	I-Application
distribute	O
the	O
work	O
over	O
the	O
set	O
of	O
virtual	B-Architecture
machines	I-Architecture
.	O
</s>
<s>
To	O
accommodate	O
a	O
large	O
number	O
of	O
cloud	B-Architecture
users	I-Architecture
,	O
cloud	B-Architecture
applications	I-Architecture
can	O
be	O
multitenant	B-Architecture
,	O
meaning	O
that	O
any	O
machine	O
may	O
serve	O
more	O
than	O
one	O
cloud-user	O
organization	O
.	O
</s>
<s>
The	O
pricing	O
model	O
for	O
SaaS	B-Architecture
applications	B-Application
is	O
typically	O
a	O
monthly	O
or	O
yearly	O
flat	O
fee	O
per	O
user	O
,	O
so	O
prices	O
become	O
scalable	B-Architecture
and	O
adjustable	O
if	O
users	O
are	O
added	O
or	O
removed	O
at	O
any	O
point	O
.	O
</s>
<s>
It	B-General_Concept
may	O
also	O
be	O
free	O
.	O
</s>
<s>
Proponents	O
claim	O
that	O
SaaS	B-Architecture
gives	O
a	O
business	O
the	O
potential	O
to	O
reduce	O
IT	B-General_Concept
operational	O
costs	O
by	O
outsourcing	B-Architecture
hardware	O
and	O
software	B-General_Concept
maintenance	O
and	O
support	O
to	O
the	O
cloud	O
provider	O
.	O
</s>
<s>
This	O
enables	O
the	O
business	O
to	O
reallocate	O
IT	B-General_Concept
operations	O
costs	O
away	O
from	O
hardware/software	O
spending	O
and	O
from	O
personnel	O
expenses	O
,	O
towards	O
meeting	O
other	O
goals	O
.	O
</s>
<s>
In	O
addition	O
,	O
with	O
applications	B-Application
hosted	O
centrally	O
,	O
updates	O
can	O
be	O
released	O
without	O
the	O
need	O
for	O
users	O
to	O
install	O
new	O
software	B-General_Concept
.	O
</s>
<s>
One	O
drawback	O
of	O
SaaS	B-Architecture
comes	O
with	O
storing	O
the	O
users	O
 '	O
data	O
on	O
the	O
cloud	O
provider	O
's	O
server	O
.	O
</s>
<s>
Examples	O
of	O
applications	B-Application
offered	O
as	O
SaaS	B-Architecture
are	O
games	B-Application
and	O
productivity	O
software	B-General_Concept
like	O
Google	B-Application
Docs	I-Application
and	O
Office	O
Online	O
.	O
</s>
<s>
SaaS	B-Architecture
applications	B-Application
may	O
be	O
integrated	O
with	O
cloud	O
storage	O
or	O
File	B-Application
hosting	I-Application
services	I-Application
,	O
which	O
is	O
the	O
case	O
with	O
Google	B-Application
Docs	I-Application
being	O
integrated	O
with	O
Google	B-Application
Drive	I-Application
,	O
and	O
Office	O
Online	O
being	O
integrated	O
with	O
OneDrive	B-Application
.	O
</s>
<s>
In	O
the	O
mobile	O
"	O
backend	O
"	O
as	O
a	O
service	O
(	O
m	O
)	O
model	O
,	O
also	O
known	O
as	O
"	O
backend	O
as	O
a	O
service	O
"	O
(	O
BaaS	O
)	O
,	O
web	B-Application
app	I-Application
and	O
mobile	B-Application
app	I-Application
developers	O
are	O
provided	O
with	O
a	O
way	O
to	O
link	O
their	O
applications	B-Application
to	O
cloud	O
storage	O
and	O
cloud	B-Architecture
computing	I-Architecture
services	O
with	O
application	B-Application
programming	I-Application
interfaces	I-Application
(	O
APIs	B-Application
)	O
exposed	O
to	O
their	O
applications	B-Application
and	O
custom	O
software	B-Application
development	I-Application
kits	I-Application
(	O
SDKs	O
)	O
.	O
</s>
<s>
Services	O
include	O
user	O
management	O
,	O
push	B-General_Concept
notifications	I-General_Concept
,	O
integration	O
with	O
social	O
networking	O
services	O
and	O
more	O
.	O
</s>
<s>
This	O
is	O
a	O
relatively	O
recent	O
model	O
in	O
cloud	B-Architecture
computing	I-Architecture
,	O
with	O
most	O
BaaS	O
startups	O
dating	O
from	O
2011	O
or	O
later	O
but	O
trends	O
indicate	O
that	O
these	O
services	O
are	O
gaining	O
significant	O
mainstream	O
traction	O
with	O
enterprise	O
consumers	O
.	O
</s>
<s>
Serverless	B-General_Concept
computing	I-General_Concept
is	O
a	O
cloud	B-Architecture
computing	I-Architecture
code	O
execution	B-General_Concept
model	O
in	O
which	O
the	O
cloud	O
provider	O
fully	O
manages	O
starting	O
and	O
stopping	O
virtual	B-Architecture
machines	I-Architecture
as	O
necessary	O
to	O
serve	O
requests	O
,	O
and	O
requests	O
are	O
billed	O
by	O
an	O
abstract	B-Application
measure	O
of	O
the	O
resources	O
required	O
to	O
satisfy	O
the	O
request	O
,	O
rather	O
than	O
per	O
virtual	B-Architecture
machine	I-Architecture
,	O
per	O
hour	O
.	O
</s>
<s>
Despite	O
the	O
name	O
,	O
it	B-General_Concept
does	O
not	O
actually	O
involve	O
running	O
code	O
without	O
servers	O
.	O
</s>
<s>
Serverless	B-General_Concept
computing	I-General_Concept
is	O
so	O
named	O
because	O
the	O
business	O
or	O
person	O
that	O
owns	O
the	O
system	O
does	O
not	O
have	O
to	O
purchase	O
,	O
rent	O
or	O
provide	O
servers	O
or	O
virtual	B-Architecture
machines	I-Architecture
for	O
the	O
back-end	O
code	O
to	O
run	O
on	O
.	O
</s>
<s>
Function	O
as	O
a	O
service	O
(	O
FaaS	O
)	O
is	O
a	O
service-hosted	O
remote	O
procedure	O
call	O
that	O
leverages	O
serverless	B-General_Concept
computing	I-General_Concept
to	O
enable	O
the	O
deployment	O
of	O
individual	O
functions	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
that	O
run	O
in	O
response	O
to	O
events	O
.	O
</s>
<s>
FaaS	O
is	O
considered	O
by	O
some	O
to	O
come	O
under	O
the	O
umbrella	O
of	O
serverless	B-General_Concept
computing	I-General_Concept
,	O
while	O
some	O
others	O
use	O
the	O
terms	O
interchangeably	O
.	O
</s>
<s>
Undertaking	O
a	O
private	O
cloud	O
project	O
requires	O
significant	O
engagement	O
to	O
virtualize	B-General_Concept
the	O
business	O
environment	O
,	O
and	O
requires	O
the	O
organization	O
to	O
reevaluate	O
decisions	O
about	O
existing	O
resources	O
.	O
</s>
<s>
It	B-General_Concept
can	O
improve	O
business	O
,	O
but	O
every	O
step	O
in	O
the	O
project	O
raises	O
security	O
issues	O
that	O
must	O
be	O
addressed	O
to	O
prevent	O
serious	O
vulnerabilities	O
.	O
</s>
<s>
Self-run	O
data	B-Operating_System
centers	I-Operating_System
are	O
generally	O
capital	O
intensive	O
.	O
</s>
<s>
They	O
have	O
attracted	O
criticism	O
because	O
users	O
"	O
still	O
have	O
to	O
buy	O
,	O
build	O
,	O
and	O
manage	O
them	O
"	O
and	O
thus	O
do	O
not	O
benefit	O
from	O
less	O
hands-on	O
management	O
,	O
essentially	O
"[lacking]	O
the	O
economic	O
model	O
that	O
makes	O
cloud	B-Architecture
computing	I-Architecture
such	O
an	O
intriguing	O
concept	O
"	O
.	O
</s>
<s>
Cloud	B-Architecture
services	I-Architecture
are	O
considered	O
"	O
public	O
"	O
when	O
they	O
are	O
delivered	O
over	O
the	O
public	O
Internet	O
,	O
and	O
they	O
may	O
be	O
offered	O
as	O
a	O
paid	O
subscription	O
,	O
or	O
free	O
of	O
charge	O
.	O
</s>
<s>
Architecturally	O
,	O
there	O
are	O
few	O
differences	O
between	O
public	O
-	O
and	O
private-cloud	O
services	O
,	O
but	O
security	O
concerns	O
increase	O
substantially	O
when	O
services	O
(	O
applications	B-Application
,	O
storage	O
,	O
and	O
other	O
resources	O
)	O
are	O
shared	O
by	O
multiple	O
customers	O
.	O
</s>
<s>
Most	O
public-cloud	O
providers	O
offer	O
direct-connection	O
services	O
that	O
allow	O
customers	O
to	O
securely	O
link	O
their	O
legacy	O
data	B-Operating_System
centers	I-Operating_System
to	O
their	O
cloud-resident	O
applications	B-Application
.	O
</s>
<s>
Several	O
factors	O
like	O
the	O
functionality	O
of	O
the	O
solutions	O
,	O
cost	O
,	O
integrational	O
and	O
organizational	O
aspects	O
as	O
well	O
as	O
safety	O
&	O
security	O
are	O
influencing	O
the	O
decision	O
of	O
enterprises	O
and	O
organizations	O
to	O
choose	O
a	O
public	O
cloud	O
or	O
on-premises	B-General_Concept
solution	O
.	O
</s>
<s>
Hybrid	O
cloud	O
is	O
a	O
composition	O
of	O
a	O
public	O
cloud	O
and	O
a	O
private	O
environment	O
,	O
such	O
as	O
a	O
private	O
cloud	O
or	O
on-premises	B-General_Concept
resources	O
,	O
that	O
remain	O
distinct	O
entities	O
but	O
are	O
bound	O
together	O
,	O
offering	O
the	O
benefits	O
of	O
multiple	O
deployment	O
models	O
.	O
</s>
<s>
Gartner	O
defines	O
a	O
hybrid	O
cloud	B-Architecture
service	I-Architecture
as	O
a	O
cloud	B-Architecture
computing	I-Architecture
service	O
that	O
is	O
composed	O
of	O
some	O
combination	O
of	O
private	O
,	O
public	O
and	O
community	B-General_Concept
cloud	I-General_Concept
services	O
,	O
from	O
different	O
service	O
providers	O
.	O
</s>
<s>
A	O
hybrid	O
cloud	B-Architecture
service	I-Architecture
crosses	O
isolation	O
and	O
provider	O
boundaries	O
so	O
that	O
it	B-General_Concept
cannot	O
be	O
simply	O
put	O
in	O
one	O
category	O
of	O
private	O
,	O
public	O
,	O
or	O
community	B-General_Concept
cloud	I-General_Concept
service	I-Architecture
.	O
</s>
<s>
It	B-General_Concept
allows	O
one	O
to	O
extend	O
either	O
the	O
capacity	O
or	O
the	O
capability	O
of	O
a	O
cloud	B-Architecture
service	I-Architecture
,	O
by	O
aggregation	O
,	O
integration	O
or	O
customization	O
with	O
another	O
cloud	B-Architecture
service	I-Architecture
.	O
</s>
<s>
For	O
example	O
,	O
an	O
organization	O
may	O
store	O
sensitive	O
client	O
data	O
in	O
house	O
on	O
a	O
private	O
cloud	B-Architecture
application	I-Architecture
,	O
but	O
interconnect	O
that	O
application	O
to	O
a	O
business	O
intelligence	O
application	O
provided	O
on	O
a	O
public	O
cloud	O
as	O
a	O
software	B-General_Concept
service	O
.	O
</s>
<s>
This	O
example	O
of	O
hybrid	O
cloud	O
extends	O
the	O
capabilities	O
of	O
the	O
enterprise	O
to	O
deliver	O
a	O
specific	O
business	O
service	O
through	O
the	O
addition	O
of	O
externally	O
available	O
public	O
cloud	B-Architecture
services	I-Architecture
.	O
</s>
<s>
Hybrid	O
cloud	O
adoption	O
depends	O
on	O
a	O
number	O
of	O
factors	O
such	O
as	O
data	O
security	O
and	O
compliance	O
requirements	O
,	O
level	O
of	O
control	O
needed	O
over	O
data	O
,	O
and	O
the	O
applications	B-Application
an	O
organization	O
uses	O
.	O
</s>
<s>
Another	O
example	O
of	O
hybrid	O
cloud	O
is	O
one	O
where	O
IT	B-General_Concept
organizations	O
use	O
public	O
cloud	B-Architecture
computing	I-Architecture
resources	O
to	O
meet	O
temporary	O
capacity	O
needs	O
that	O
can	O
not	O
be	O
met	O
by	O
the	O
private	O
cloud	O
.	O
</s>
<s>
This	O
capability	O
enables	O
hybrid	O
clouds	O
to	O
employ	O
cloud	O
bursting	O
for	O
scaling	B-Architecture
across	O
clouds	O
.	O
</s>
<s>
Cloud	O
bursting	O
is	O
an	O
application	O
deployment	O
model	O
in	O
which	O
an	O
application	O
runs	O
in	O
a	O
private	O
cloud	O
or	O
data	B-Operating_System
center	I-Operating_System
and	O
"	O
bursts	O
"	O
to	O
a	O
public	O
cloud	O
when	O
the	O
demand	O
for	O
computing	O
capacity	O
increases	O
.	O
</s>
<s>
Cloud	O
bursting	O
enables	O
data	B-Operating_System
centers	I-Operating_System
to	O
create	O
an	O
in-house	B-Architecture
IT	B-Application
infrastructure	I-Application
that	O
supports	O
average	O
workloads	O
,	O
and	O
use	O
cloud	O
resources	O
from	O
public	O
or	O
private	O
clouds	O
,	O
during	O
spikes	O
in	O
processing	O
demands	O
.	O
</s>
<s>
The	O
specialized	O
model	O
of	O
hybrid	O
cloud	O
,	O
which	O
is	O
built	O
atop	O
heterogeneous	O
hardware	O
,	O
is	O
called	O
"	O
Cross-platform	B-Operating_System
Hybrid	O
Cloud	O
"	O
.	O
</s>
<s>
A	O
cross-platform	B-Operating_System
hybrid	O
cloud	O
is	O
usually	O
powered	O
by	O
different	O
CPU	O
architectures	O
,	O
for	O
example	O
,	O
x86-64	O
and	O
ARM	O
,	O
underneath	O
.	O
</s>
<s>
Users	O
can	O
transparently	O
deploy	O
and	O
scale	B-Architecture
applications	B-Application
without	O
knowledge	O
of	O
the	O
cloud	O
's	O
hardware	O
diversity	O
.	O
</s>
<s>
Hybrid	O
cloud	O
infrastructure	O
essentially	O
serves	O
to	O
eliminate	O
limitations	O
inherent	O
to	O
the	O
multi-access	O
relay	O
characteristics	O
of	O
private	O
cloud	B-Architecture
networking	I-Architecture
.	O
</s>
<s>
The	O
advantages	O
include	O
enhanced	O
runtime	O
flexibility	O
and	O
adaptive	O
memory	O
processing	O
unique	O
to	O
virtualized	B-General_Concept
interface	O
models	O
.	O
</s>
<s>
Community	B-General_Concept
cloud	I-General_Concept
shares	O
infrastructure	O
between	O
several	O
organizations	O
from	O
a	O
specific	O
community	O
with	O
common	O
concerns	O
(	O
security	O
,	O
compliance	O
,	O
jurisdiction	O
,	O
etc	O
.	O
</s>
<s>
The	O
costs	O
are	O
spread	O
over	O
fewer	O
users	O
than	O
a	O
public	O
cloud	O
(	O
but	O
more	O
than	O
a	O
private	O
cloud	O
)	O
,	O
so	O
only	O
some	O
of	O
the	O
cost	O
savings	O
potential	O
of	O
cloud	B-Architecture
computing	I-Architecture
are	O
realized	O
.	O
</s>
<s>
A	O
cloud	B-Architecture
computing	I-Architecture
platform	I-Architecture
can	O
be	O
assembled	O
from	O
a	O
distributed	B-Architecture
set	O
of	O
machines	O
in	O
different	O
locations	O
,	O
connected	O
to	O
a	O
single	O
network	O
or	O
hub	O
service	O
.	O
</s>
<s>
It	B-General_Concept
is	O
possible	O
to	O
distinguish	O
between	O
two	O
types	O
of	O
distributed	B-Architecture
clouds	O
:	O
public-resource	O
computing	O
and	O
volunteer	O
cloud	O
.	O
</s>
<s>
Public-resource	O
computing	O
This	O
type	O
of	O
distributed	B-Architecture
cloud	O
results	O
from	O
an	O
expansive	O
definition	O
of	O
cloud	B-Architecture
computing	I-Architecture
,	O
because	O
they	O
are	O
more	O
akin	O
to	O
distributed	B-Architecture
computing	I-Architecture
than	O
cloud	B-Architecture
computing	I-Architecture
.	O
</s>
<s>
Nonetheless	O
,	O
it	B-General_Concept
is	O
considered	O
a	O
sub-class	O
of	O
cloud	B-Architecture
computing	I-Architecture
.	O
</s>
<s>
Volunteer	O
cloud	O
Volunteer	O
cloud	B-Architecture
computing	I-Architecture
is	O
characterized	O
as	O
the	O
intersection	O
of	O
public-resource	O
computing	O
and	O
cloud	B-Architecture
computing	I-Architecture
,	O
where	O
a	O
cloud	B-Architecture
computing	I-Architecture
infrastructure	O
is	O
built	O
using	O
volunteered	O
resources	O
.	O
</s>
<s>
Many	O
challenges	O
arise	O
from	O
this	O
type	O
of	O
infrastructure	O
,	O
because	O
of	O
the	O
volatility	O
of	O
the	O
resources	O
used	O
to	O
build	O
it	B-General_Concept
and	O
the	O
dynamic	O
environment	O
it	B-General_Concept
operates	O
in	O
.	O
</s>
<s>
It	B-General_Concept
can	O
also	O
be	O
called	O
peer-to-peer	O
clouds	O
,	O
or	O
ad-hoc	O
clouds	O
.	O
</s>
<s>
An	O
interesting	O
effort	O
in	O
such	O
direction	O
is	O
Cloud	O
@Home	O
,	O
it	B-General_Concept
aims	O
to	O
implement	O
a	O
cloud	B-Architecture
computing	I-Architecture
infrastructure	O
using	O
volunteered	O
resources	O
providing	O
a	O
business-model	O
to	O
incentivize	O
contributions	O
through	O
financial	O
restitution	O
.	O
</s>
<s>
Multicloud	O
is	O
the	O
use	O
of	O
multiple	O
cloud	B-Architecture
computing	I-Architecture
services	O
in	O
a	O
single	O
heterogeneous	O
architecture	O
to	O
reduce	O
reliance	O
on	O
single	O
vendors	O
,	O
increase	O
flexibility	O
through	O
choice	O
,	O
mitigate	O
against	O
disasters	O
,	O
etc	O
.	O
</s>
<s>
It	B-General_Concept
differs	O
from	O
hybrid	O
cloud	O
in	O
that	O
it	B-General_Concept
refers	O
to	O
multiple	O
cloud	B-Architecture
services	I-Architecture
,	O
rather	O
than	O
multiple	O
deployment	O
modes	O
(	O
public	O
,	O
private	O
,	O
legacy	O
)	O
.	O
</s>
<s>
It	B-General_Concept
differs	O
from	O
Multi	O
cloud	O
in	O
that	O
it	B-General_Concept
is	O
not	O
designed	O
to	O
increase	O
flexibility	O
or	O
mitigate	O
against	O
failures	O
but	O
is	O
rather	O
used	O
to	O
allow	O
an	O
organization	O
to	O
achieve	O
more	O
that	O
could	O
be	O
done	O
with	O
a	O
single	O
provider	O
.	O
</s>
<s>
The	O
issues	O
of	O
transferring	O
large	O
amounts	O
of	O
data	O
to	O
the	O
cloud	O
as	O
well	O
as	O
data	O
security	O
once	O
the	O
data	O
is	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
initially	O
hampered	O
adoption	O
of	O
cloud	O
for	O
big	B-Application
data	I-Application
,	O
but	O
now	O
that	O
much	O
data	O
originates	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
and	O
with	O
the	O
advent	O
of	O
bare-metal	B-General_Concept
servers	I-General_Concept
,	O
the	O
cloud	O
has	O
become	O
a	O
solution	O
for	O
use	O
cases	O
including	O
business	O
analytics	O
and	O
geospatial	B-General_Concept
analysis	I-General_Concept
.	O
</s>
<s>
HPC	O
cloud	O
refers	O
to	O
the	O
use	O
of	O
cloud	B-Architecture
computing	I-Architecture
services	O
and	O
infrastructure	O
to	O
execute	O
high-performance	B-Architecture
computing	I-Architecture
(	O
HPC	O
)	O
applications	B-Application
.	O
</s>
<s>
These	O
applications	B-Application
consume	O
a	O
considerable	O
amount	O
of	O
computing	O
power	O
and	O
memory	O
and	O
are	O
traditionally	O
executed	O
on	O
clusters	B-Architecture
of	O
computers	O
.	O
</s>
<s>
In	O
2016	O
a	O
handful	O
of	O
companies	O
,	O
including	O
R-HPC	O
,	O
Amazon	B-Application
Web	I-Application
Services	I-Application
,	O
Univa	B-General_Concept
,	O
Silicon	O
Graphics	O
International	O
,	O
Sabalcore	O
,	O
Gomput	O
,	O
and	O
Penguin	O
Computing	O
offered	O
a	O
high-performance	B-Architecture
computing	I-Architecture
cloud	O
.	O
</s>
<s>
The	O
Penguin	O
On	O
Demand	O
(	O
POD	O
)	O
cloud	O
was	O
one	O
of	O
the	O
first	O
non-virtualized	O
remote	O
HPC	O
services	O
offered	O
on	O
a	O
pay-as-you-go	O
basis	O
.	O
</s>
<s>
Penguin	O
Computing	O
launched	O
its	O
HPC	O
cloud	O
in	O
2016	O
as	O
an	O
alternative	O
to	O
Amazon	B-Application
's	O
EC2	O
Elastic	B-General_Concept
Compute	I-General_Concept
Cloud	I-General_Concept
,	O
which	O
uses	O
virtualized	B-General_Concept
computing	O
nodes	O
.	O
</s>
<s>
Cloud	B-General_Concept
architecture	I-General_Concept
,	O
the	O
systems	B-Architecture
architecture	I-Architecture
of	O
the	O
software	B-General_Concept
systems	O
involved	O
in	O
the	O
delivery	O
of	O
cloud	B-Architecture
computing	I-Architecture
,	O
typically	O
involves	O
multiple	O
cloud	O
components	O
communicating	O
with	O
each	O
other	O
over	O
a	O
loose	B-Application
coupling	I-Application
mechanism	O
such	O
as	O
a	O
messaging	O
queue	O
.	O
</s>
<s>
Elastic	O
provision	O
implies	O
intelligence	O
in	O
the	O
use	O
of	O
tight	O
or	O
loose	B-Application
coupling	I-Application
as	O
applied	O
to	O
mechanisms	O
such	O
as	O
these	O
and	O
others	O
.	O
</s>
<s>
Cloud	B-General_Concept
engineering	I-General_Concept
is	O
the	O
application	O
of	O
engineering	O
disciplines	O
of	O
cloud	B-Architecture
computing	I-Architecture
.	O
</s>
<s>
It	B-General_Concept
brings	O
a	O
systematic	O
approach	O
to	O
the	O
high-level	O
concerns	O
of	O
commercialization	O
,	O
standardization	O
and	O
governance	O
in	O
conceiving	O
,	O
developing	O
,	O
operating	O
and	O
maintaining	O
cloud	B-Architecture
computing	I-Architecture
systems	O
.	O
</s>
<s>
It	B-General_Concept
is	O
a	O
multidisciplinary	O
method	O
encompassing	O
contributions	O
from	O
diverse	O
areas	O
such	O
as	O
systems	O
,	O
software	B-General_Concept
,	O
web	O
,	O
performance	B-General_Concept
,	O
information	B-Application
technology	I-Application
engineering	I-Application
,	O
security	O
,	O
platform	O
,	O
risk	O
,	O
and	O
quality	O
engineering	O
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
poses	O
privacy	O
concerns	O
because	O
the	O
service	O
provider	O
can	O
access	O
the	O
data	O
that	O
is	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
at	O
any	O
time	O
.	O
</s>
<s>
It	B-General_Concept
could	O
accidentally	O
or	O
deliberately	O
alter	O
or	O
delete	O
information	O
.	O
</s>
<s>
That	O
is	O
permitted	O
in	O
their	O
privacy	O
policies	O
,	O
which	O
users	O
must	O
agree	O
to	O
before	O
they	O
start	O
using	O
cloud	B-Architecture
services	I-Architecture
.	O
</s>
<s>
Identity	O
management	O
systems	O
can	O
also	O
provide	O
practical	O
solutions	O
to	O
privacy	O
concerns	O
in	O
cloud	B-Architecture
computing	I-Architecture
.	O
</s>
<s>
According	O
to	O
the	O
Cloud	B-General_Concept
Security	I-General_Concept
Alliance	O
,	O
the	O
top	O
three	O
threats	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
are	O
Insecure	O
Interfaces	O
and	O
APIs	B-Application
,	O
Data	O
Loss	O
&	O
Leakage	O
,	O
and	O
Hardware	O
Failure	O
—	O
which	O
accounted	O
for	O
29%	O
,	O
25%	O
and	O
10%	O
of	O
all	O
cloud	B-General_Concept
security	I-General_Concept
outages	O
respectively	O
.	O
</s>
<s>
"	O
There	O
are	O
some	O
real	O
Achilles	O
 '	O
heels	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
infrastructure	O
that	O
are	O
making	O
big	O
holes	O
for	O
the	O
bad	O
guys	O
to	O
get	O
into	O
"	O
.	O
</s>
<s>
Because	O
data	O
from	O
hundreds	O
or	O
thousands	O
of	O
companies	O
can	O
be	O
stored	O
on	O
large	O
cloud	B-General_Concept
servers	I-General_Concept
,	O
hackers	O
can	O
theoretically	O
gain	O
control	O
of	O
huge	O
stores	O
of	O
information	O
through	O
a	O
single	O
attack	O
—	O
a	O
process	O
he	O
called	O
"	O
hyperjacking	O
"	O
.	O
</s>
<s>
Dropbox	O
had	O
been	O
breached	O
in	O
October	O
2014	O
,	O
having	O
over	O
7	O
million	O
of	O
its	O
users	O
passwords	O
stolen	O
by	O
hackers	O
in	O
an	O
effort	O
to	O
get	O
monetary	O
value	O
from	O
it	B-General_Concept
by	O
Bitcoins	O
(	O
BTC	O
)	O
.	O
</s>
<s>
There	O
is	O
the	O
problem	O
of	O
legal	O
ownership	O
of	O
the	O
data	O
(	O
If	O
a	O
user	O
stores	O
some	O
data	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
,	O
can	O
the	O
cloud	O
provider	O
profit	O
from	O
it	B-General_Concept
?	O
)	O
.	O
</s>
<s>
This	O
delivers	O
great	O
incentive	O
to	O
public	O
cloud	B-Architecture
computing	I-Architecture
service	O
providers	O
to	O
prioritize	O
building	O
and	O
maintaining	O
strong	O
management	O
of	O
secure	O
services	O
.	O
</s>
<s>
Some	O
small	O
businesses	O
that	O
do	O
n't	O
have	O
expertise	O
in	O
IT	B-General_Concept
security	O
could	O
find	O
that	O
it	B-General_Concept
's	O
more	O
secure	O
for	O
them	O
to	O
use	O
a	O
public	O
cloud	O
.	O
</s>
<s>
There	O
is	O
the	O
risk	O
that	O
end	O
users	O
do	O
not	O
understand	O
the	O
issues	O
involved	O
when	O
signing	O
on	O
to	O
a	O
cloud	B-Architecture
service	I-Architecture
(	O
persons	O
sometimes	O
do	O
n't	O
read	O
the	O
many	O
pages	O
of	O
the	O
terms	O
of	O
service	O
agreement	O
,	O
and	O
just	O
click	O
"	O
Accept	O
"	O
without	O
reading	O
)	O
.	O
</s>
<s>
This	O
is	O
important	O
now	O
that	O
cloud	B-Architecture
computing	I-Architecture
is	O
common	O
and	O
required	O
for	O
some	O
services	O
to	O
work	O
,	O
for	O
example	O
for	O
an	O
intelligent	B-Protocol
personal	I-Protocol
assistant	I-Protocol
(	O
Apple	O
's	O
Siri	B-Application
or	O
Google	B-Application
Assistant	I-Application
)	O
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
is	O
cheaper	O
because	O
of	O
economics	O
of	O
scale	B-Architecture
,	O
and	O
—	O
like	O
any	O
outsourced	O
task	O
—	O
you	O
tend	O
to	O
get	O
what	O
you	O
get	O
.	O
</s>
<s>
Fewer	O
options	O
at	O
a	O
much	O
cheaper	O
price	O
:	O
it	B-General_Concept
's	O
a	O
feature	O
,	O
not	O
a	O
bug.	O
"	O
</s>
<s>
He	O
also	O
suggests	O
that	O
"	O
the	O
cloud	O
provider	O
might	O
not	O
meet	O
your	O
legal	O
needs	O
"	O
and	O
that	O
businesses	O
need	O
to	O
weigh	O
the	O
benefits	O
of	O
cloud	B-Architecture
computing	I-Architecture
against	O
the	O
risks	O
.	O
</s>
<s>
In	O
cloud	B-Architecture
computing	I-Architecture
,	O
the	O
control	O
of	O
the	O
back	O
end	O
infrastructure	O
is	O
limited	O
to	O
the	O
cloud	O
vendor	O
only	O
.	O
</s>
<s>
Cloud	O
providers	O
often	O
decide	O
on	O
the	O
management	O
policies	O
,	O
which	O
moderates	O
what	O
the	O
cloud	B-Architecture
users	I-Architecture
are	O
able	O
to	O
do	O
with	O
their	O
deployment	O
.	O
</s>
<s>
Cloud	B-Architecture
users	I-Architecture
are	O
also	O
limited	O
to	O
the	O
control	O
and	O
management	O
of	O
their	O
applications	B-Application
,	O
data	O
and	O
services	O
.	O
</s>
<s>
This	O
includes	O
data	O
caps	O
,	O
which	O
are	O
placed	O
on	O
cloud	B-Architecture
users	I-Architecture
by	O
the	O
cloud	O
vendor	O
allocating	O
a	O
certain	O
amount	O
of	O
bandwidth	O
for	O
each	O
customer	O
and	O
are	O
often	O
shared	O
among	O
other	O
cloud	B-Architecture
users	I-Architecture
.	O
</s>
<s>
Due	O
to	O
the	O
use	O
of	O
the	O
internet	O
,	O
confidential	O
information	O
such	O
as	O
employee	O
data	O
and	O
user	O
data	O
can	O
be	O
easily	O
available	O
to	O
third-party	O
organisations	O
and	O
people	O
in	O
cloud	B-Architecture
computing	I-Architecture
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
has	O
some	O
limitations	O
for	O
smaller	O
business	O
operations	O
,	O
particularly	O
regarding	O
security	O
and	O
downtime	O
.	O
</s>
<s>
Technical	O
outages	O
are	O
inevitable	O
and	O
occur	O
sometimes	O
when	O
cloud	B-Architecture
service	I-Architecture
providers	I-Architecture
(	O
CSPs	O
)	O
become	O
overwhelmed	O
in	O
the	O
process	O
of	O
serving	O
their	O
clients	O
.	O
</s>
<s>
Since	O
this	O
technology	O
's	O
systems	O
rely	O
on	O
the	O
Internet	O
,	O
an	O
individual	O
cannot	O
access	O
their	O
applications	B-Application
,	O
server	O
,	O
or	O
data	O
from	O
the	O
cloud	O
during	O
an	O
outage	O
.	O
</s>
<s>
Cloud	B-Architecture
computing	I-Architecture
is	O
still	O
a	O
subject	O
of	O
research	O
.	O
</s>
<s>
A	O
driving	O
factor	O
in	O
the	O
evolution	O
of	O
cloud	B-Architecture
computing	I-Architecture
has	O
been	O
chief	O
technology	O
officers	O
seeking	O
to	O
minimize	O
risk	O
of	O
internal	O
outages	O
and	O
mitigate	O
the	O
complexity	O
of	O
housing	O
network	O
and	O
computing	O
hardware	O
in-house	B-Architecture
.	O
</s>
<s>
Since	O
the	O
global	O
pandemic	O
of	O
2020	O
,	O
cloud	B-Architecture
technology	I-Architecture
jumped	O
ahead	O
in	O
popularity	O
due	O
to	O
the	O
level	O
of	O
security	O
of	O
data	O
and	O
the	O
flexibility	O
of	O
working	O
options	O
for	O
all	O
employees	O
,	O
notably	O
remote	O
workers	O
.	O
</s>
<s>
An	O
alternative	O
approach	O
is	O
to	O
deploy	O
a	O
tool	O
that	O
processes	O
in	B-Architecture
the	I-Architecture
cloud	I-Architecture
itself	O
.	O
</s>
