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:
So
f
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as
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Ser
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latf
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m
a
s
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(
P
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d
I
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as
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as
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Ser
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ai
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g
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clo
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p
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all
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ar
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’
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k
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p
in
g
th
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d
atac
en
ter
s
w
o
r
k
i
n
g
[
1
]
.
C
lo
u
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c
o
m
p
u
ti
n
g
h
as
cr
ea
ted
a
q
u
an
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m
leap
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in
f
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m
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tech
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f
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elast
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T
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d
if
f
er
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n
t
s
ec
to
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s
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f
d
ev
elo
p
ed
cites
[
2
]
.
T
h
e
d
ep
lo
y
m
en
t
m
o
d
els
o
f
clo
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s
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it’s
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er
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h
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s
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w
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a
m
p
le
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ar
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az
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d
Mic
r
o
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t.
Mo
s
t
l
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P
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ate
C
lo
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d
is
u
s
ed
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I
t
is
ap
p
r
o
p
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iate
f
o
r
a
s
in
g
le
o
r
g
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izatio
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C
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m
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s
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an
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t
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at
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m
m
o
n
i
n
ter
est
s
.
H
y
b
r
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clo
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d
is
a
m
er
g
e
o
f
p
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w
it
h
p
u
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C
lo
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d
m
o
d
el
in
o
r
d
er
to
p
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s
ev
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d
if
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er
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t
f
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a
li
ties
w
it
h
in
t
h
e
s
a
m
e
co
m
p
a
n
y
[
3
]
.
I
n
2
0
1
6
f
in
a
n
cia
l
in
v
est
m
e
n
t
o
n
clo
u
d
co
m
p
u
t
in
g
w
ill
b
e
Glo
b
al
co
m
p
o
u
n
d
an
n
u
al
g
r
o
w
th
r
at
e
o
f
I
aa
S 4
1
%,
P
aa
S 2
6
.
6
% a
n
d
SaaS
1
7
.
4
%
[
3
]
.
C
lo
u
d
co
m
p
u
tin
g
h
as b
i
g
ef
f
e
ct
o
n
d
ev
elo
p
ed
cities.
Go
v
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n
m
en
t G
-
clo
u
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s
ar
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p
r
o
m
is
i
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m
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d
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s
f
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d
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p
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cities
th
at
ca
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co
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d
eliv
er
p
latf
o
r
m
s
f
o
r
s
m
all
b
u
s
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n
es
s
ap
p
licatio
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s
.
T
h
e
UK
g
o
v
er
n
m
e
n
t
’
s
G
-
clo
u
d
is
a
n
ex
e
m
p
lar
y
in
i
tiatio
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i
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th
i
s
r
eg
ar
d
.
C
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d
co
m
p
u
ti
n
g
g
i
v
es
o
p
p
o
r
tu
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it
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to
d
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IJ
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25
d
if
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er
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n
t
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s
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u
p
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p
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cities
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r
p
ar
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ev
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s
tics
.
I
n
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d
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a
s
th
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p
o
ten
tial
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W
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ld
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s
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m
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g
p
o
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T
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a
n
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s
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C
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also
o
p
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n
e
w
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s
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t
itu
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b
y
d
ig
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n
e
s
[
2
]
.
T
h
is
p
ap
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co
n
tain
in
ad
d
itio
n
to
s
ec
tio
n
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n
e
s
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t
w
o
,
will
p
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t
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clo
u
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p
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s
ec
u
r
it
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attac
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,
s
ec
tio
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th
r
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w
ill p
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n
t p
r
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p
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s
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s
y
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m
d
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g
n
,
Sectio
n
f
o
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r
w
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l p
r
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t r
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lt t
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p
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p
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tio
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f
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h
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co
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cl
u
s
io
n
o
f
th
e
o
f
th
is
p
ap
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.
2.
CL
O
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CO
M
P
UT
I
N
G
SE
CURI
T
Y
AT
T
ACK
C
lo
u
d
co
m
p
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ti
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g
o
f
f
er
s
a
v
ar
i
et
y
o
f
s
er
v
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i
n
cl
u
d
in
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s
to
r
ag
e.
C
lo
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d
s
to
r
ag
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h
a
s
m
an
y
d
r
a
w
b
ac
k
s
o
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th
is
L
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s
s
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P
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y
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ica
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C
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e
o
f
co
n
ce
r
n
s
:
a.
C
o
n
tr
o
l
o
v
er
u
s
er
d
ata
o
r
o
r
g
an
iza
tio
n
d
ata
m
a
y
b
e
co
m
i
n
g
led
i
n
v
ar
io
u
s
w
a
y
s
w
it
h
d
ata
b
elo
n
g
in
g
to
o
th
er
s
[
4
]
.
b.
I
n
s
ec
u
r
e
A
P
I
s
an
d
i
n
ter
f
ac
e
s
:
c.
T
h
er
e
ar
e
g
r
o
u
p
o
f
A
P
I
s
o
r
s
o
f
t
w
ar
e
i
n
ter
f
ac
e
s
p
r
o
v
id
ed
b
y
cl
o
u
d
s
u
p
p
lier
s
f
o
r
u
s
er
s
to
co
n
tr
o
l
an
d
in
ter
ac
t
w
it
h
s
er
v
ices
p
r
o
v
id
ed
b
y
t
h
e
clo
u
d
.
T
h
e
av
ailab
ilit
y
an
d
s
ec
u
r
it
y
o
f
clo
u
d
s
er
v
ice
s
is
r
el
y
o
n
th
e
s
ec
u
r
it
y
o
f
th
e
s
e
b
asic
A
P
I
s
.
T
h
is
A
P
I
s
m
u
s
t
b
e
d
esig
n
ed
in
a
s
ec
u
r
it
y
w
a
y
to
p
r
o
tect
ag
ain
s
t
attac
k
s
an
d
m
alici
o
u
s
atte
m
p
ts
to
cir
cu
m
v
en
t
p
o
lic
y
.
Or
g
an
iza
tio
n
s
b
u
ild
u
p
o
n
t
h
ese
in
ter
f
ac
es
to
o
f
f
er
ad
d
itio
n
al
s
er
v
ices
to
th
eir
cu
s
to
m
er
s
d.
Ma
licio
u
s
I
n
s
id
er
s
e.
T
h
e
m
alicio
u
s
i
n
s
id
er
s
is
a
m
p
l
if
ied
f
o
r
cu
s
to
m
er
o
f
clo
u
d
b
y
th
e
co
n
v
er
g
e
n
ce
o
f
I
T
s
er
v
ices
an
d
cu
s
to
m
er
u
n
d
er
a
s
i
n
g
le
m
a
n
ag
e
m
e
n
t d
o
m
ai
n
f.
Data
lo
s
s
o
r
leak
ag
e
g.
T
h
e
p
r
o
ce
s
s
o
f
alter
atio
n
o
r
d
e
letio
n
d
ata
w
i
th
o
u
t
k
ee
p
i
n
g
a
b
ac
k
u
p
o
f
t
h
e
o
r
ig
i
n
al
co
p
y
,
d
at
a
w
ill
b
e
lo
s
s
.
I
lleg
al
u
s
er
s
m
u
s
t b
e
b
lo
ck
f
r
o
m
ac
ce
s
s
to
s
e
n
s
iti
v
e
d
ata
[
5
]
.
h.
Den
ial
o
f
s
er
v
ice
i.
T
h
e
d
en
ial
-
of
-
s
er
v
ice
attac
k
b
lo
ck
leg
al
u
s
er
s
f
r
o
m
ac
ce
s
s
i
n
g
th
eir
d
ata.
T
h
e
d
en
ial
-
of
-
s
er
v
i
ce
attac
k
ca
n
alter
th
e
e
n
cr
y
p
tio
n
k
e
y
o
r
s
l
o
w
t
h
e
s
y
s
te
m
to
b
lo
ck
u
s
er
s
f
r
o
m
u
s
in
g
t
h
e
s
er
v
ice
b
y
tr
y
in
g
to
u
s
e
t
h
e
w
r
o
n
g
p
ass
w
o
r
d
m
o
r
e
t
h
an
o
n
ce
.
T
h
er
ef
o
r
clo
u
d
s
er
v
ice
p
r
o
v
id
er
s
s
h
o
u
ld
d
ev
elo
p
a
m
ec
h
an
is
m
s
o
t
h
at
th
e
attac
k
er
s
ca
n
n
o
t i
m
p
ac
t o
n
th
e
s
er
v
ice
s
p
r
o
v
id
e
b
y
t
h
e
cl
o
u
d
[
6
]
.
j.
Ven
d
o
r
lo
ck
-
i
n
:
k.
On
e
o
f
th
e
co
n
ce
r
n
s
t
h
at
i
s
o
f
ten
o
v
er
lo
o
k
ed
w
h
e
n
ch
o
o
s
i
n
g
a
clo
u
d
p
r
o
v
id
er
is
v
e
n
d
o
r
lo
ck
in
:
clo
u
d
s
er
v
ice
p
r
o
v
id
er
b
lo
ck
th
e
s
er
v
ices
p
r
o
v
id
ed
to
th
e
cu
s
to
m
e
r
s
u
ch
t
h
at
c
u
s
to
m
er
ca
n
n
o
t
a
cc
ess
h
is
d
ata
an
d
u
s
e
a
n
y
s
er
v
ice
s
p
r
o
v
id
ed
b
y
t
h
e
clo
u
d
o
r
ca
n
n
o
t
m
o
v
e
d
ata
to
o
th
er
p
r
o
v
id
er
.
l.
SQL
i
n
j
ec
tio
n
:
m.
I
t
is
d
o
n
e
b
y
in
s
er
ti
n
g
SQ
L
o
r
d
er
s
in
a
d
atab
ase
o
f
an
ap
p
licatio
n
f
r
o
m
th
e
w
e
b
to
S
m
as
h
in
g
th
at
d
atab
ase
.
n.
Gu
est
-
h
o
p
p
in
g
attac
k
o.
T
h
e
attac
k
er
tr
ies
to
ac
ce
s
s
to
v
ir
tu
a
l
m
ac
h
i
n
e
b
y
b
r
ea
k
t
h
r
o
u
g
h
o
th
er
v
ir
t
u
al
m
ac
h
in
e
h
o
s
te
d
in
th
e
s
a
m
e
h
ar
d
w
ar
e.
T
h
e
c
h
ar
ac
ter
is
tic
s
o
f
p
u
b
lic
clo
u
d
co
m
p
u
ti
n
g
ar
e
d
ef
in
e
b
y
m
u
ltip
le
r
e
n
tal
s
an
d
s
h
ar
ed
r
eso
u
r
ce
s
.
T
h
is
t
y
p
e
o
f
attac
k
er
s
ex
p
lo
its
th
e
f
ail
u
r
e
o
f
s
ep
ar
atio
n
m
ec
h
a
n
i
s
m
s
th
at
u
s
ed
to
s
ep
ar
ate
th
e
u
s
a
g
e
o
f
s
to
r
a
g
e
an
d
h
ar
d
w
ar
e
[
7
]
p.
B
r
u
te
f
o
r
ce
attac
k
q.
A
b
r
u
te
f
o
r
ce
attac
k
u
s
ed
to
g
et
u
s
er
in
f
o
r
m
a
tio
n
s
u
c
h
as
a
p
ass
w
o
r
d
,
o
r
p
er
s
o
n
al
id
en
tifi
ca
tio
n
n
u
m
b
er
.
An
a
u
to
m
a
tic
s
o
f
t
w
ar
e
in
a
b
r
u
te
f
o
r
ce
attac
k
is
u
s
ed
to
g
en
er
ate
a
b
ig
n
u
m
b
er
o
f
co
n
s
ec
u
tiv
e
g
u
ess
e
s
as
to
th
e
v
al
u
e
o
f
t
h
e
d
esire
d
d
ata.
T
h
is
t
y
p
e
p
er
h
ap
s
u
s
ed
b
y
s
ec
u
r
it
y
a
n
al
y
s
t
s
to
test
a
n
o
r
g
an
izat
io
n
'
s
n
et
w
o
r
k
s
ec
u
r
it
y
o
r
b
y
cr
i
m
i
n
als to
cr
ac
k
en
cr
y
p
ted
d
ata
[
8
]
.
r.
A
cc
o
u
n
t o
r
Ser
v
ice
Hij
ac
k
i
n
g
s.
I
s
a
w
a
y
s
o
f
f
r
a
u
d
,
p
h
is
h
i
n
g
an
d
v
u
ln
er
ab
ilit
y
ex
p
lo
r
atio
n
m
o
r
eo
v
er
p
ass
w
o
r
d
cr
ed
en
tials
u
s
ed
in
d
is
tr
ib
u
ted
m
et
h
o
d
s
g
iv
e
b
r
ea
d
th
to
th
is
p
r
o
b
lem
.
T
h
e
an
x
iet
y
w
i
th
ab
d
u
ctio
n
o
f
ac
co
u
n
ts
w
a
s
th
e
g
o
al
o
f
m
an
y
clo
u
d
s
er
v
ice
p
r
o
v
id
er
s
alr
ea
d
y
co
n
s
o
lid
ated
in
t
h
e
m
a
r
k
et,
s
u
c
h
as
Am
az
o
n
.
3.
P
RO
P
O
SE
D
SYS
T
E
M
F
O
R
CL
O
UD
S
T
O
RA
G
E
T
h
e
p
r
o
p
o
s
ed
s
y
s
te
m
m
ak
e
s
e
cu
r
it
y
to
lo
g
i
n
p
r
o
ce
s
s
an
d
s
to
r
ed
d
ata
in
th
e
clo
u
d
s
to
r
ag
e
i
n
cr
ea
s
e
b
y
u
s
i
n
g
t
h
ir
d
p
ar
t
y
au
th
e
n
ticat
io
n
a
n
d
o
n
e
ti
m
e
p
as
s
w
o
r
d
an
d
en
cr
y
p
t
s
to
r
e
d
ata
b
y
m
o
d
i
f
ie
d
A
E
S
a
lg
o
r
it
h
m
s
.
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26
Her
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p
licatio
n
p
r
o
g
r
a
m
i
n
g
i
n
ter
f
ac
e)
ask
ed
f
o
r
r
eg
is
tr
atio
n
an
d
th
e
n
th
e
FC
M
w
ill
r
esp
o
n
s
e
w
it
h
m
es
s
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e
o
f
u
n
iq
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s
tr
in
g
(
to
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en
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g
e
n
er
ated
f
o
r
p
ar
ticu
lar
u
s
er
s
m
ar
t
p
h
o
n
e.
T
h
is
to
k
en
w
ill
b
e
s
to
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e
in
t
h
e
clo
u
d
d
atab
ase
ac
co
r
d
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g
to
u
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er
n
a
m
e
a
n
d
p
ass
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o
r
d
to
u
s
i
n
g
it
w
h
en
s
e
n
d
o
r
r
ec
eiv
e
n
o
ti
f
icat
io
n
o
n
m
o
b
il
e.
Af
ter
to
k
en
s
to
r
ed
in
t
h
e
clo
u
d
d
atab
ase
th
e
u
s
er
co
m
p
lete
th
e
p
r
o
ce
s
s
o
f
r
eg
is
tr
atio
n
an
d
ca
n
lo
g
in
to
cl
o
u
d
at
an
y
ti
m
e
a
n
d
f
r
o
m
a
n
y
w
h
er
e
b
y
u
s
i
n
g
h
is
i
n
f
o
r
m
atio
n
.
F
i
g
u
r
e
2
.
E
x
p
lai
n
th
e
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tep
s
o
f
r
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tr
atio
n
p
r
o
ce
s
s
.
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ter
co
m
p
lete
th
e
p
r
o
ce
s
s
o
f
r
eg
is
ter
i
n
g
h
is
ac
co
u
n
t
o
n
th
e
clo
u
d
s
to
r
ag
e
an
d
th
e
C
o
r
r
esp
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n
d
in
g
th
ir
d
p
ar
ty
d
ev
ice,
n
o
w
ca
n
lo
g
i
n
to
clo
u
d
.
Yo
u
m
u
s
t
e
n
ter
th
e
p
r
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v
io
u
s
l
y
r
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g
is
ter
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s
er
n
a
m
e
a
n
d
if
v
alid
S
y
s
te
m
w
il
l
g
en
er
ate
th
e
o
n
e
ti
m
e
p
a
s
s
w
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d
u
s
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g
c
h
ao
tic
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te
m
.
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h
is
ch
ao
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te
m
i
s
n
o
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li
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er
eq
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atio
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lled
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u
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s
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h
ao
tic
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atio
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h
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t
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ate
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d
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m
n
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t
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e
p
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ed
icted
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s
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ti
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p
ass
w
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n
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e
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p
ir
ed
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ter
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al
f
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h
o
u
r
o
r
o
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e
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s
e
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h
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d
u
p
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eq
u
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e
o
f
th
e
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m
p
o
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tan
t
eq
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atio
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t
h
at
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ec
u
r
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I
t sh
o
w
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i
n
eq
u
atio
n
1
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Xn+
1
=
c2
s
in
(
π
c1
s
in (
π
*
X
n))
(
1
)
E
q
u
atio
n
1
: d
u
p
le
s
i
n
ch
ao
tic
eq
u
atio
n
T
h
e
o
n
e
ti
m
e
p
ass
w
o
r
d
th
at
g
e
n
er
ated
f
r
o
m
t
h
e
ch
ao
tic
s
y
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te
m
w
ill
b
e
s
e
n
d
to
th
e
u
s
er
o
n
m
o
b
ile
t
h
e
n
th
e
u
s
er
ca
n
u
s
ed
th
is
r
ec
eiv
ed
p
ass
w
o
r
d
o
n
m
o
b
ile
ap
p
licatio
n
C
o
m
b
in
e
s
w
i
th
th
e
s
ta
tic
p
ass
w
o
r
d
th
at
u
s
ed
in
th
e
r
eg
i
s
tr
atio
n
a
s
a
p
ass
w
o
r
d
to
lo
g
in
t
h
e
clo
u
d
a
n
d
u
s
in
g
cl
o
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d
s
to
r
ag
e
to
s
to
r
e
h
i
s
d
ata,
b
r
o
w
s
es
h
i
s
f
ile
t
h
at
s
to
r
ed
o
n
th
e
clo
u
d
s
to
r
ag
e
an
d
d
o
w
n
lo
ad
in
g
an
y
f
ile,
F
i
g
u
r
e
3
ex
p
lain
th
e
lo
g
in
o
p
er
atio
n
.
Evaluation Warning : The document was created with Spire.PDF for Python.
IJ
-
I
C
T
I
SS
N
:
2252
-
8776
I
mp
r
o
ve
S
ec
u
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ity
o
f Cl
o
u
d
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to
r
a
g
e
b
y
Usi
n
g
Th
ir
d
P
a
r
ity
A
u
th
en
tica
tio
n
.
.
.
(
F
ir
a
s
A
.
A
b
d
u
l
a
tif
)
27
Fig
u
r
e
2
.
R
eg
i
s
tr
atio
n
P
r
o
ce
s
s
Fig
u
r
e
3
.
L
o
g
i
n
P
r
o
ce
s
s
to
C
lo
u
d
Sto
r
ag
e
W
h
en
th
e
u
s
er
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g
i
n
to
th
e
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u
d
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e
ca
n
u
s
e
all
th
e
f
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s
p
r
o
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id
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y
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e
s
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te
m
s
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c
h
as b
r
o
w
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n
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ile
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h
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s
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d
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n
d
ca
n
d
o
w
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lo
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an
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f
ile
a
n
d
r
ea
d
it
an
d
ca
n
u
p
lo
ad
an
y
f
ile
to
clo
u
d
s
to
r
ag
e.
User
ch
o
s
e
s
f
ile
to
u
p
lo
ad
it
to
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d
s
to
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ag
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a
n
d
b
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A
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S e
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p
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al
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o
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ith
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as o
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o
f
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r
it
y
to
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ec
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r
e
s
en
s
iti
v
e
d
ata.
T
h
e
A
E
S e
n
c
r
y
p
tio
n
al
g
o
r
ith
m
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s
o
n
e
o
f
th
e
m
o
s
t
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m
p
o
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tan
t
S
y
n
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h
r
o
n
ic
cr
y
p
to
g
r
ap
h
ic
al
g
o
r
ith
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h
ich
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s
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h
ar
ac
ter
ized
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y
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h
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s
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o
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lt
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o
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o
d
in
g
th
e
k
e
y
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n
cr
y
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tio
n
.
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h
e
m
o
d
if
ied
A
E
S
en
cr
y
p
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io
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alg
o
r
ith
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u
s
ed
th
e
ex
p
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s
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n
k
e
y
m
et
h
o
d
w
i
th
d
o
u
b
le
s
in
c
h
ao
tic
s
y
s
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m
to
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en
er
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en
cr
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k
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A
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g
o
r
ith
m
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p
lai
n
ex
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s
io
n
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e
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m
et
h
o
d
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d
alg
o
r
ith
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2
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p
lai
n
t
h
e
m
o
d
if
ied
A
E
S e
n
cr
y
p
tio
n
alg
o
r
it
h
m
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
2
5
2
-
8776
IJ
-
I
C
T
Vo
l.
7
,
No
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1
,
A
p
r
il
20
1
8
:
24
–
30
28
Alg
o
r
ith
m
(1
):
Ex
p
a
n
sio
n
k
e
y
a
lg
o
r
ith
m
Inp
u
t
:
k
e
y
a
s a
n
a
rra
y
o
f
3
2
w
o
rd
w
it
h
4
c
o
l
u
m
n
a
n
d
8
ro
w
,
NK
=
8
O
u
t
p
u
t:
w
a
s a
t
w
o
d
im
e
n
sio
n
k
e
y
a
rra
y
B
e
g
in
:
S
te
p
1
:
f
o
r
i
=
1
to
8
B
e
g
in
S
te
p
2
:
a
rra
y
r
=
(k
e
y
[
4
*
i]
,
k
e
y
[
4
*
i
+
1
],
k
e
y
[
4
*
i
+
2
]
,
k
e
y
[
4
*
i
+
3
]
)
S
te
p
3
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w
[
i]
=
r
En
d
S
te
p
4
:
f
o
r
i
=
8
t
o
6
0
B
e
g
in
S
tep
5
:
f
o
r
t
=
1
to
4
B
e
g
in
S
tep
6
:
a
rra
y
te
m
p
[
t]
=
w
[
i
-
1
]
[
t
]
En
d
S
tep
7
:
if
(I
m
o
d
8
=
0
)
B
e
g
in
S
tep
8
:
sh
if
t
ro
w
(tem
p
)
S
tep
9
:
se
t
t=1
to
4
d
o
ste
p
1
0
B
e
g
in
S
tep
1
0
:
tem
p
[t
]
=
tem
p
[
t
]
A
ND
rCo
n
[
i
/
8
][
t
]
En
d
Else
B
e
g
in
S
tep
1
1
:
if
(NK
>
6
&
&
i
m
o
d
Nk
=
4
)
B
e
g
in
S
tep
1
2
:
tem
p
=
s
-
b
o
x
(tem
p
)
S
tep
1
3
:
s
h
if
t
ro
w
(te
m
p
)
En
d
En
d
S
tep
1
4
:
h
=
1
t
o
4
B
e
g
in
S
tep
1
5
:
w
[
i
][t
]
=
w
[
i
-
Nk
][
t
]
A
ND
tem
p
[
t]
En
d
En
d
En
d
En
d
S
tep
1
6
:
re
t
u
rn
(w
)
En
d
.
Evaluation Warning : The document was created with Spire.PDF for Python.
IJ
-
I
C
T
I
SS
N
:
2252
-
8776
I
mp
r
o
ve
S
ec
u
r
ity
o
f Cl
o
u
d
S
to
r
a
g
e
b
y
Usi
n
g
Th
ir
d
P
a
r
ity
A
u
th
en
tica
tio
n
.
.
.
(
F
ir
a
s
A
.
A
b
d
u
l
a
tif
)
29
4.
RE
SU
L
T
4
.
1
.
T
est
R
a
nd
o
m
ize
T
o
test
th
e
r
an
d
o
m
ize
o
f
th
e
m
o
d
i
f
ie
s
A
E
S
en
cr
y
p
t
io
n
al
g
o
r
ith
m
s
,
w
e
u
s
e
C
r
y
p
to
o
l
1
.
4
.
3
0
s
o
f
t
w
ar
e,
T
ab
le
1
h
as
th
e
r
es
u
lt
o
f
t
h
e
f
iv
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b
asic
tes
ts
o
f
t
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ta
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d
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A
E
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-
2
5
6
b
its
co
m
p
ar
ed
w
it
h
th
e
m
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d
i
f
ies
A
E
S
-
2
5
6
b
its
en
cr
y
p
tio
n
al
g
o
r
it
h
m
.
T
ab
le
1
.
Fiv
e
B
asic T
est o
f
AE
S a
n
d
Mo
d
if
ied
A
E
S E
n
cr
y
p
tio
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A
lg
o
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it
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m
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t
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F
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q
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R
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e
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n
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e
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i
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st
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P
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ss
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a
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e
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t
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o
ch
ec
k
t
h
e
in
p
u
t
i
n
f
o
r
m
atio
n
p
r
ec
is
el
y
to
av
o
id
SQ
L
in
j
ec
ti
o
n
.
RE
F
E
R
E
NC
E
[1
]
C.
M
.
R.
Da
S
i
lv
a
,
J.
L
.
C.
Da
S
il
v
a
,
R.
B
.
R
o
d
rig
u
e
s,
G
.
M
.
M
.
Ca
m
p
o
s,
L
.
M
.
Do
Na
sc
im
e
n
to
,
V
.
C.
G
a
rc
ia.
“
S
e
c
u
rit
y
th
re
a
ts
in
c
lo
u
d
c
o
m
p
u
ti
n
g
m
o
d
e
ls:
Do
m
a
in
s
a
n
d
p
r
o
p
o
sa
ls,
”
IEE
E
In
t.
C
o
n
f
.
Cl
o
u
d
C
o
mp
u
t.
CL
OU
D
,
2
0
1
3
:
3
8
3
–
3
8
9
.
[2
]
T
.
K.
Da
m
e
n
u
,
C.
Ba
lak
rish
n
a
.
“
Clo
u
d
S
e
c
u
rit
y
Risk
M
a
n
a
g
e
m
e
n
t:
A
Crit
ica
l
Re
v
ie
w
,
”
N
e
x
t
Ge
n
e
r.
M
o
b
.
Ap
p
l
.
S
e
rv
.
T
e
c
h
n
o
l.
2
0
1
5
9
th
In
t
.
Co
n
f.
,
2
0
1
5
:
3
7
0
–
3
7
5
,
.
[3
]
M.
Irf
a
n
,
M
.
Us
m
a
n
,
Y.
Zh
u
a
n
g
,
S
.
F
o
n
g
.
“
A
Crit
ica
l
Re
v
iew
o
f
S
e
c
u
rit
y
T
h
re
a
ts
in
Clo
u
d
Co
m
p
u
ti
n
g
,
”
C
o
mp
u
t.
Bu
s.
I
n
tell.
(
IS
CBI),
2
0
1
5
3
rd
In
t
.
S
y
mp
.
,
2
0
1
5
:
1
0
5
–
1
1
1
,
.
[4
]
J.
Do
m
z
a
l
.
“
S
e
c
u
rin
g
t
h
e
c
lo
u
d
:
Clo
u
d
c
o
mp
u
ter
se
c
u
rity
tec
h
n
iq
u
e
s
a
n
d
ta
c
ti
c
s
”
(
W
in
k
ler
,
V
.
;
2
0
1
1
)
[
Bo
o
k
re
v
iews
]
,
2
0
1
1
;
4
9
(
9
)
.
[5
]
Clo
u
d
S
e
c
u
rit
y
A
ll
ian
c
e
.
“
T
o
p
T
h
re
a
ts t
o
Clo
u
d
C
o
m
p
u
ti
n
g
,
”
S
e
c
u
rity
,
n
o
.
M
a
rc
h
,
2
0
1
0
:
1
–
14
.
[6
]
A
.
He
n
d
re
,
K.
P
.
Jo
s
h
i.
“
A
S
e
m
a
n
ti
c
A
p
p
ro
a
c
h
to
Clo
u
d
S
e
c
u
rit
y
a
n
d
Co
m
p
li
a
n
c
e
,
”
Pro
c
.
-
2
0
1
5
IE
E
E
8
th
I
nt
.
C
o
n
f
.
Clo
u
d
Co
m
p
u
t
.
CL
OU
D 2
0
1
5
,
2
0
1
5
:
1
0
8
1
–
1
0
8
4
.
[7
]
C.
S
tan
d
a
rd
s,
C.
Co
u
n
c
il
.
“
S
e
c
u
ri
ty
f
o
r
Clo
u
d
Co
m
p
u
ti
n
g
T
e
n
S
tep
s to
E
n
su
re
S
u
c
c
e
ss
,
”
2
0
1
5
.
[8
]
S
.
S
.
M
a
n
ik
a
n
d
a
sa
ra
n
.
“
S
e
c
u
rit
y
A
tt
a
c
k
s
a
n
d
Cr
y
p
to
g
ra
p
h
y
S
o
lu
ti
o
n
s
f
o
r
Da
ta
S
to
re
d
i
n
P
u
b
l
ic
Clo
u
d
S
t
o
ra
g
e
,
”
IRA
CS
T
-
In
t
.
J
.
C
o
mp
u
t.
S
c
i
.
In
f.
T
e
c
h
n
o
l.
S
e
c
u
r.
(
IJ
CS
IT
S
),
2
0
1
6
;
6:
4
9
8
–
5
0
3
.
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