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m
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se
n
siti
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d
a
ta an
d
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f
o
rm
a
ti
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n
.
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h
is
p
a
p
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th
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m
ig
ra
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u
a
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m
a
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th
e
se
c
u
rit
y
in
c
lo
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d
c
o
m
p
u
ti
n
g
.
V
ir
tu
a
l
m
a
c
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in
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(VM)
is
a
n
e
m
u
latio
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o
f
a
p
a
rti
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lar
c
o
m
p
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ter
sy
ste
m
.
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c
lo
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m
p
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ti
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g
,
v
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u
a
l
m
a
c
h
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m
ig
r
a
ti
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is
a
u
se
f
u
l
to
o
l
f
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m
ig
ra
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p
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ti
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g
sy
st
e
m
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sta
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s
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p
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l
m
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is
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b
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f
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lt
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e
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rg
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su
m
p
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n
.
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irt
u
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m
a
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h
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e
(V
M
)
m
ig
ra
ti
o
n
is
a
p
o
w
e
r
f
u
l
m
a
n
a
g
e
m
e
n
t
tec
h
n
iq
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e
th
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t
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s
d
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ta
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ter o
p
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ra
to
rs t
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b
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lac
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m
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t
o
f
V
M
s in
o
rd
e
r
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tt
e
r
sa
ti
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p
e
r
f
o
r
m
a
n
c
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o
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jec
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s,
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m
p
ro
v
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so
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rc
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u
ti
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z
a
ti
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n
a
n
d
c
o
m
m
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ica
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o
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lo
c
a
li
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,
a
c
h
iev
e
f
a
u
lt
to
lera
n
c
e
,
re
d
u
c
e
e
n
e
rg
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c
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n
su
m
p
ti
o
n
,
a
n
d
f
a
c
il
it
a
te
s
y
ste
m
m
a
in
ten
a
n
c
e
a
c
ti
v
it
ies
.
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t
h
e
m
ig
ra
ti
o
n
b
a
se
d
se
c
u
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a
p
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ro
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c
h
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m
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th
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b
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se
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a
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a
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d
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a
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in
(D
T
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C)
a
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a
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sis,
w
e
d
e
sig
n
a
n
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g
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h
m
th
a
t
g
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e
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p
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m
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t
a
r
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g
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m
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n
t
th
a
t
th
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st
VMs
c
a
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m
o
v
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s
b
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f
o
re
su
c
c
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e
d
s th
e
a
tt
a
c
k
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K
ey
w
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d
:
C
lo
u
d
co
m
p
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C
lo
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Sec
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it
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DT
MC
Mig
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VM
Su
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v
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ab
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rig
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©
2
0
1
8
In
stit
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te o
f
A
d
v
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d
E
n
g
i
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g
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rig
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C
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p
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A
uth
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:
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pt
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Scie
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cu
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ar
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in
s
ta
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in
th
e
s
a
m
e
p
h
y
s
i
ca
l
m
ac
h
i
n
es.
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m
e
o
f
VM
s
w
o
r
k
i
n
g
i
n
th
e
s
a
m
e
s
u
b
n
et
o
r
p
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m
a
y
co
llab
o
r
ate
in
o
r
d
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to
co
m
p
lete
a
s
er
v
ice.
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o
llab
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atin
g
w
it
h
v
u
l
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ab
le
VM
s
o
r
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n
n
in
g
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t
h
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p
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w
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u
s
VM
s
w
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in
cr
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ec
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r
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k
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s
b
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VM
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v
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a
n
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w
o
r
k
o
r
s
h
ar
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p
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s
ica
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r
eso
u
r
ce
s
w
i
ll
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n
tr
o
d
u
ce
att
ac
k
s
.
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h
e
e
x
ter
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al
ad
v
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ar
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ca
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co
m
p
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m
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e
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ab
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h
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n
f
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w
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n
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at
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t
h
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s
a
m
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p
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.
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n
o
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i
m
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th
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s
ec
u
r
it
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o
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n
tire
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d
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p
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en
t
s
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ch
w
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m
i
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ate
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it
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m
a
t
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w
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p
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m
e
n
t
p
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s
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lo
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v
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t
u
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m
ac
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cr
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n
a
v
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tu
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ter
to
b
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p
lace
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o
n
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eso
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s
w
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t
h
m
atc
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n
g
p
o
licies.
W
it
h
t
h
e
in
cr
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s
e
i
n
t
h
e
p
o
p
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lar
it
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o
f
clo
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d
co
m
p
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ti
n
g
s
y
s
te
m
s
,
v
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t
u
al
m
ac
h
i
n
e
m
i
g
r
atio
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s
ac
r
o
s
s
d
ata
ce
n
ter
s
an
d
r
eso
u
r
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p
o
o
ls
w
ill
b
e
g
r
ea
tly
b
e
n
ef
ic
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to
d
ata
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n
ter
ad
m
i
n
is
tr
ato
r
s
.
C
lo
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co
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p
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g
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s
r
ap
id
ly
at
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ac
tiv
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m
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a
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o
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v
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in
co
m
p
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g
in
f
r
astru
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An
ex
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p
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m
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s
p
lace
m
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t
s
tr
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is
s
h
o
w
n
i
n
Fi
g
u
r
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1
.
E
ac
h
VM
o
n
ev
er
y
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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&
C
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m
p
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n
g
I
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N:
2088
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8708
Mig
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tio
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ve
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ity
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(
N
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n
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ka
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)
211
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o
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(
p
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)
m
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x
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er
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d
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o
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ar
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o
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r
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.
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p
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m
e
n
t stra
te
g
y
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a
p
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b
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clo
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d
.
Fig
u
r
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1
.
Vir
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m
ac
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es p
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t stra
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n
n
in
g
i
n
an
is
o
lated
p
ar
titi
o
n
w
i
th
i
n
t
h
e
co
m
p
u
ter
.
T
h
er
e
w
ill
b
e
m
u
ltip
le
v
i
r
t
u
al
m
ac
h
i
n
es
r
u
n
n
i
n
g
o
n
to
p
o
f
a
s
i
n
g
le
p
h
y
s
ical
m
ac
h
i
n
e.
W
h
e
n
o
n
e
p
h
y
s
ical
h
o
s
t g
e
ts
o
v
er
lo
ad
ed
,
it
m
a
y
b
e
r
eq
u
ir
ed
to
d
y
n
a
m
i
ca
ll
y
tr
a
n
s
f
er
ce
r
tai
n
a
m
o
u
n
t
o
f
i
ts
lo
ad
to
an
o
t
h
e
r
m
ac
h
i
n
e
w
it
h
m
in
i
m
al
i
n
te
r
r
u
p
tio
n
to
t
h
e
u
s
er
s
.
T
h
is
p
r
o
ce
s
s
o
f
m
o
v
i
n
g
a
vi
r
tu
a
l
m
ac
h
i
n
e
f
r
o
m
o
n
e
p
h
y
s
ical
h
o
s
t
to
a
n
o
th
er
i
s
ter
m
ed
as
m
ig
r
at
io
n
.
I
n
th
e
p
ast,
to
m
o
v
e
a
VM
b
et
w
ee
n
t
w
o
p
h
y
s
ical
h
o
s
ts
,
it
w
a
s
n
ec
ess
ar
y
to
s
h
u
t
d
o
w
n
t
h
e
VM
,
allo
ca
te
th
e
n
ee
d
ed
r
eso
u
r
ce
s
to
th
e
n
e
w
p
h
y
s
ica
l
h
o
s
t,
m
o
v
e
th
e
VM
f
ile
s
an
d
s
tar
t
th
e
VM
i
n
t
h
e
n
e
w
h
o
s
t.
T
h
e
liv
e
m
i
g
r
atio
n
m
a
k
es
p
o
s
s
ib
le
f
o
r
VM
s
to
b
e
m
i
g
r
ated
w
it
h
o
u
t
co
n
s
id
er
ab
le
d
o
w
n
ti
m
e.
T
h
e
tr
an
s
f
er
o
f
a
VM
ac
tu
all
y
r
e
f
er
s
to
th
e
tr
an
s
f
er
o
f
its
s
ta
te.
T
h
is
in
cl
u
d
es
it
s
m
e
m
o
r
y
,
in
ter
n
al
s
tate
o
f
th
e
d
e
v
ices
a
n
d
t
h
at
o
f
t
h
e
v
ir
tu
al
C
P
U.
Am
o
n
g
th
e
s
e,
th
e
m
o
s
t
T
i
m
e
-
co
n
s
u
m
i
n
g
o
n
e
is
t
h
e
m
e
m
o
r
y
tr
an
s
f
er
.
W
e
h
av
e
alr
ea
d
y
f
o
u
n
d
m
a
n
y
attac
k
s
ag
a
in
s
t
v
u
ln
er
ab
ili
ties
in
clo
u
d
h
y
p
er
v
i
s
o
r
an
d
th
e
co
n
tr
o
l V
M.
Fo
r
ex
a
m
p
le,
s
o
m
e
ad
v
er
s
a
r
ies
ex
p
lo
it
th
e
v
u
l
n
er
ab
ilit
i
es
o
f
clo
u
d
h
y
p
er
v
is
o
r
(
e.
g
.
C
VE
-
2007
-
4
9
9
3
,
2
0
0
7
)
.
On
ce
th
e
y
co
m
p
r
o
m
i
s
e
th
e
h
y
p
er
v
is
o
r
(
e.
g
.
KVM
an
d
Xen
)
,
th
e
u
s
er
s
’
VM
s
w
ill
b
e
tak
e
n
o
v
er
.
So
m
e
o
th
er
attac
k
er
s
w
ill
p
lace
a
m
alicio
u
s
VM
i
n
t
h
e
p
u
b
lic
c
lo
u
d
an
d
co
m
p
r
o
m
is
e
t
h
e
V
Ms
r
u
n
n
i
n
g
in
th
e
s
a
m
e
p
h
y
s
ical
s
er
v
er
b
y
s
id
e
ch
a
n
n
el
attac
k
[
1
]
.
A
d
d
itio
n
all
y
,
t
h
e
ad
v
er
s
ar
y
ca
n
f
in
d
th
e
n
ex
t
tar
g
et
b
y
an
al
y
zi
n
g
th
e
n
et
w
o
r
k
co
n
n
ec
tio
n
s
o
f
co
m
p
r
o
m
is
ed
VM
s
.
2.
RE
L
AT
E
D
WO
RK
I
n
I
T
in
d
u
s
tr
y
,
d
i
f
f
er
en
t
co
m
p
u
tin
g
n
ee
d
s
ar
e
p
r
o
v
id
ed
as
a
s
er
v
ice.
T
h
er
e
ar
e
m
a
n
y
b
en
ef
its
o
f
u
s
i
n
g
t
h
e
tec
h
n
o
lo
g
y
a
v
ailab
le
f
r
o
m
clo
u
d
s
er
v
ice
p
r
o
v
id
er
s
,
s
u
ch
as
ac
ce
s
s
to
lar
g
e
-
s
ca
le,
o
n
-
d
e
m
a
n
d
,
f
le
x
ib
le
co
m
p
u
ti
n
g
i
n
f
r
a
s
tr
u
ct
u
r
es.
Ho
w
e
v
er
,
i
n
cr
ea
s
i
n
g
t
h
e
d
ep
en
d
ab
ilit
y
o
f
clo
u
d
co
m
p
u
tin
g
i
s
i
m
p
o
r
tan
t
i
n
o
r
d
er
f
o
r
its
p
o
ten
tial
to
b
e
r
ea
lized
.
Data
s
ec
u
r
it
y
i
s
o
n
e
o
f
t
h
e
m
o
s
t
cr
itical
asp
ec
ts
i
n
a
clo
u
d
co
m
p
u
ti
n
g
en
v
ir
o
n
m
e
n
t
d
u
e
to
th
e
s
en
s
iti
v
it
y
a
n
d
i
m
p
o
r
tan
ce
o
f
t
h
e
in
f
o
r
m
at
io
n
s
to
r
ed
in
th
e
clo
u
d
,
as
is
th
e
tr
u
s
t
w
o
r
t
h
in
e
s
s
o
f
t
h
e
clo
u
d
s
er
v
ice
p
r
o
v
id
er
.
T
h
e
r
is
k
o
f
m
alicio
u
s
i
n
s
id
er
s
i
n
th
e
clo
u
d
an
d
th
e
f
ail
u
r
e
o
f
clo
u
d
s
er
v
ice
s
h
av
e
r
ec
ei
v
e
d
in
ten
s
e
atte
n
tio
n
b
y
c
lo
u
d
u
s
er
s
[
2
]
.
T
h
e
clo
u
d
co
m
p
u
ti
n
g
p
r
o
v
id
e
s
an
o
p
p
o
r
tu
n
it
y
o
f
d
e
v
elo
p
m
e
n
t
an
d
en
v
ir
o
n
m
en
t
f
o
r
n
e
w
s
er
v
ice
p
atter
n
o
f
m
u
lt
i
-
s
o
u
r
ce
i
n
f
o
r
m
atio
n
s
er
v
ice
(
MSI
S).
T
h
e
is
s
u
es
a
s
s
o
ciate
d
w
it
h
clo
u
d
co
m
p
u
ti
n
g
a
n
d
t
h
e
n
atu
r
e
p
ar
t
o
f
t
h
e
r
elatio
n
b
et
w
ee
n
MSI
S
an
d
clo
u
d
co
m
p
u
t
in
g
[
3
]
.
C
lo
u
d
c
o
m
p
u
ti
n
g
o
f
f
er
s
d
is
tr
ib
u
ted
a
n
d
s
h
ar
ed
co
m
p
u
tin
g
r
e
s
o
u
r
c
es
an
d
s
er
v
ice
s
t
h
at
b
elo
n
g
to
d
if
f
er
en
t
s
er
v
ice
p
r
o
v
id
er
s
an
d
w
eb
s
ites
.
O
n
e
o
f
th
e
m
o
s
t
i
m
p
o
r
tan
t
a
s
p
ec
ts
th
at
n
ee
d
s
p
ec
i
al
atten
tio
n
p
er
tain
s
to
th
e
clo
u
d
s
ec
u
r
it
y
.
C
lo
u
d
co
m
p
u
t
in
g
h
as
th
e
i
m
p
o
r
tan
t
co
m
p
o
n
en
t
as
tr
u
s
t
m
an
a
g
e
m
e
n
t
[
4
]
.
T
h
e
m
aj
o
r
is
s
u
es
p
er
tai
n
i
n
g
to
d
ata
s
ec
u
r
it
y
i
n
t
h
e
clo
u
d
co
m
p
u
ti
n
g
e
n
v
ir
o
n
m
en
t
li
k
e
d
ata
lo
ca
tio
n
an
d
d
ata
tr
an
s
m
is
s
io
n
,
d
ata
av
ai
la
b
ilit
y
,
d
ata
s
ec
u
r
it
y
ar
e
d
is
c
u
s
s
ed
in
[
5
]
.
B
eh
l
[
6
]
ex
p
lo
r
es
clo
u
d
co
m
p
u
t
in
g
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
8
,
No
.
1
,
Feb
r
u
ar
y
201
8
:
2
1
0
–
2
1
9
212
s
ec
u
r
it
y
is
s
u
e
s
an
d
h
i
g
h
l
ig
h
ts
th
e
k
e
y
r
esear
ch
c
h
alle
n
g
es
t
h
at
i
n
cl
u
d
e:
av
ailab
ili
t
y
an
d
p
er
f
o
r
m
an
ce
,
m
alicio
u
s
i
n
s
id
er
s
,
o
u
t
s
id
e
att
ac
k
s
,
s
er
v
ice
d
is
r
u
p
tio
n
s
.
C
h
e
n
e
t
al.
[
7
]
d
is
c
u
s
s
clo
u
d
co
m
p
u
ti
n
g
d
ata
s
ec
u
r
it
y
a
n
d
d
ata
p
r
iv
ac
y
p
r
o
tectio
n
i
s
s
u
es.
T
h
e
s
ec
u
r
it
y
ar
ch
itect
u
r
e
is
d
e
f
i
n
ed
at
th
r
ee
le
v
els
:
s
o
f
t
w
ar
e
s
ec
u
r
it
y
,
p
lat
f
o
r
m
s
ec
u
r
it
y
,
an
d
i
n
f
r
a
s
tr
u
ct
u
r
e
s
ec
u
r
it
y
.
Data
p
r
iv
ac
y
p
r
o
tecti
o
n
is
s
u
e
s
o
f
t
h
e
d
ata
l
i
f
ec
y
cle
in
clo
u
d
co
m
p
u
ti
n
g
i
n
cl
u
d
e
t
r
an
s
f
er
,
u
s
e,
s
h
ar
e,
s
to
r
ag
e,
ar
ch
i
v
al
a
n
d
d
estr
u
cti
o
n
.
P
o
p
o
v
ic
et
al.
[
8
]
in
d
icate
s
ec
u
r
it
y
is
s
u
es
o
f
c
lo
u
d
co
m
p
u
tin
g
s
y
s
te
m
s
b
y
h
ig
h
li
g
h
ti
n
g
t
h
e
p
r
o
b
lem
s
o
f
clo
u
d
co
m
p
u
tin
g
,
p
ar
ticu
lar
l
y
,
th
e
s
ec
u
r
it
y
m
a
n
a
g
e
m
e
n
t
m
o
d
els
b
ased
o
n
s
ec
u
r
it
y
s
ta
n
d
ar
d
s
an
d
th
e
s
ec
u
r
it
y
i
s
s
u
es
p
er
tain
i
n
g
to
s
ec
u
r
it
y
s
ta
n
d
ar
d
s
.
Sian
i
et
al.
[
9
]
h
ig
h
li
g
h
t
th
at
t
h
e
m
aj
o
r
h
u
r
d
les
in
lar
g
e
-
s
ca
le
ac
ce
p
tan
ce
o
f
clo
u
d
co
m
p
u
ti
n
g
,
m
o
s
tl
y
d
u
e
to
s
er
v
ice
s
e
cu
r
it
y
a
n
d
p
r
iv
ac
y
is
s
u
es.
B
ased
o
n
th
e
d
is
c
u
s
s
e
d
s
ce
n
ar
io
s
,
it
is
r
ec
o
m
m
en
d
e
d
th
at
s
en
s
iti
v
e
i
n
f
o
r
m
atio
n
s
h
o
u
ld
b
e
m
i
n
i
m
ized
w
h
e
n
d
ata
is
p
r
o
ce
s
s
ed
o
n
clo
u
d
an
d
p
r
iv
ac
y
to
t
h
e
en
d
-
u
s
er
m
u
s
t b
e
ass
u
r
ed
.
As
t
h
e
n
u
m
b
er
o
f
d
ep
en
d
e
n
t
s
o
n
t
h
e
clo
u
d
s
er
v
ices
s
h
o
o
t
s
u
p
,
t
h
e
s
ec
u
r
it
y
i
s
s
u
e
h
as
b
ec
o
m
e
an
o
v
er
w
h
e
l
m
i
n
g
p
r
o
b
le
m
f
o
r
clo
u
d
s
er
v
ice
p
r
o
v
id
er
s
.
I
n
o
r
d
e
r
to
m
a
k
e
u
s
e
o
f
t
h
e
clo
u
d
b
en
ef
its
to
f
u
ll
e
x
te
n
t,
th
ese
i
s
s
u
es
n
ee
d
to
b
e
ad
d
r
ess
ed
f
ir
s
t.
T
h
e
m
aj
o
r
s
ec
u
r
i
t
y
is
s
u
es
i
n
clo
u
d
co
m
p
u
ti
n
g
an
d
s
o
m
e
o
f
t
h
e
co
u
n
ter
m
ea
s
u
r
es
t
h
at
ca
n
b
e
im
p
le
m
e
n
ted
ar
e
also
s
u
g
g
este
d
in
[
1
0
]
.
Da
w
ei
S
u
n
et
al.
[
1
1
]
h
as
class
i
f
ied
th
e
s
ec
u
r
it
y
is
s
u
es
i
n
to
s
i
x
ca
te
g
o
r
ies.
T
h
e
n
ee
d
f
o
r
m
o
n
ito
r
in
g
th
e
clo
u
d
s
er
v
er
,
d
ata
co
n
f
id
en
tialit
y
,
m
alicio
u
s
in
s
id
er
s
ac
ti
v
it
ies,
s
er
v
ice
h
ij
ac
k
in
g
,
is
s
u
es
d
u
e
to
m
u
lt
i
ten
an
c
y
a
n
d
s
o
o
n
ar
e
d
ea
lt
w
it
h
.
P
r
iv
ac
y
i
s
s
u
es
l
ik
e
en
ab
lin
g
u
s
er
s
to
h
a
v
e
co
n
tr
o
l
o
v
er
d
ata,
p
r
ev
en
tin
g
d
ata
lo
s
s
w
h
i
le
r
ep
licatin
g
etc
ar
e
also
d
is
cu
s
s
ed
.
D.
Z
is
s
is
,
D.
L
e
k
k
a
s
[
1
2
]
h
as
ad
d
r
ess
ed
v
ar
io
u
s
s
ec
u
r
it
y
is
s
u
e
s
lik
e
tr
u
s
t,
co
n
f
id
e
n
t
ialit
y
a
n
d
p
r
iv
ac
y
,
in
te
g
r
it
y
a
n
d
av
ai
l
ab
ilit
y
.
I
n
a
clo
u
d
e
n
v
ir
o
n
m
en
t
tr
u
s
t
w
o
r
th
in
es
s
i
s
a
r
elev
a
n
t
ter
m
as
d
at
a
is
o
u
ts
o
u
r
ce
d
o
u
t
o
f
o
w
n
er
‟s sec
u
r
it
y
b
o
u
n
d
ar
ie
s
.
J
o
h
n
C
.
R
o
b
er
ts
I
I
an
d
W
asi
m
Al
-
Ha
m
d
a
n
i
[
1
3
]
h
as
d
is
cu
s
s
ed
ab
o
u
t
“w
r
ap
p
er
attac
k
”
in
w
h
ic
h
th
e
attac
k
er
w
r
ap
s
s
o
m
e
m
a
licio
u
s
co
d
e
in
XM
L
s
i
g
n
at
u
r
e
an
d
i
n
j
ec
ts
th
i
s
s
i
g
n
at
u
r
e
in
to
t
h
e
X
ML
co
d
es
w
h
ich
is
ess
e
n
tial
i
n
clo
u
d
co
m
p
u
t
in
g
f
o
r
r
eso
u
r
ce
s
h
ar
i
n
g
.
C
lo
u
d
c
o
m
p
u
ti
n
g
h
as
b
ec
o
m
e
a
te
m
p
t
in
g
tar
g
et
f
o
r
cy
b
er
cr
i
m
e
[
1
4
]
.
T
h
e
p
r
o
m
i
n
en
t
p
r
o
v
id
er
s
lik
e
Am
az
o
n
an
d
Go
o
g
le
h
as
m
ec
h
a
n
i
s
m
s
to
d
ef
e
n
d
ag
ai
n
s
t
t
h
i
s
t
y
p
e
o
f
attac
k
.
A
c
lo
u
d
en
v
ir
o
n
m
e
n
t
co
n
s
i
s
ts
o
f
n
u
m
er
o
u
s
h
e
ter
o
g
en
eo
u
s
e
n
titi
e
s
a
n
d
th
e
s
e
cu
r
it
y
o
f
s
u
c
h
a
n
en
v
ir
o
n
m
e
n
t
is
d
ep
en
d
an
t
o
f
th
e
s
ec
u
r
it
y
g
u
ar
an
teed
b
y
t
h
e
w
ea
k
est
e
n
tit
y
.
Var
io
u
s
s
ec
u
r
i
t
y
is
s
u
e
s
[
1
5
]
in
th
e
d
if
f
er
e
n
t
d
eli
v
er
y
m
o
d
els
o
f
c
lo
u
d
th
r
ea
te
n
t
h
e
en
d
-
u
s
er
s
.
I
n
So
f
t
w
ar
e
a
s
a
Ser
v
ice
(
Saa
S)
m
o
d
el
t
h
e
y
h
av
e
q
u
o
ted
v
ar
io
u
s
is
s
u
e
s
li
k
e
d
ata
co
n
f
id
e
n
tialit
y
,
w
eb
ap
p
licatio
n
s
ec
u
r
it
y
,
d
ata
b
r
ea
ch
es,
v
ir
t
u
aliza
tio
n
v
u
l
n
er
ab
ilit
y
,
av
ailab
ili
t
y
,
b
ac
k
u
p
,
I
d
en
tit
y
m
a
n
a
g
e
m
e
n
t
an
d
s
ig
n
-
o
n
p
r
o
ce
s
s
.
T
h
e
m
an
a
g
e
m
en
t
o
f
in
f
o
r
m
atio
n
s
ec
u
r
it
y
o
p
er
atio
n
s
is
a
co
m
p
lex
ta
s
k
,
esp
ec
iall
y
in
a
clo
u
d
en
v
ir
o
n
m
en
t.
T
h
e
clo
u
d
s
er
v
ice
la
y
er
s
a
n
d
m
u
lti
-
te
n
an
c
y
v
ir
tu
a
l
ar
ch
ite
ctu
r
e
cr
ea
te
a
co
m
p
le
x
e
n
v
ir
o
n
m
e
n
t
i
n
w
h
ic
h
to
d
e
v
elo
p
an
d
m
a
n
a
g
e
an
in
f
o
r
m
a
t
io
n
s
ec
u
r
it
y
i
n
ci
d
en
t
m
an
a
g
e
m
e
n
t
a
n
d
co
m
p
li
an
ce
p
r
o
g
r
a
m
.
T
h
e
g
o
al
is
to
p
r
o
tect
clo
u
d
s
er
v
ic
es
ag
ai
n
s
t
n
e
w
an
d
e
x
i
s
tin
g
at
t
ac
k
s
a
s
w
ell
a
s
co
m
p
l
y
w
i
th
s
ec
u
r
it
y
p
o
licies
a
n
d
r
eg
u
lato
r
y
r
eq
u
ir
e
m
e
n
ts
.
T
h
e
p
r
o
p
o
s
ed
ap
p
r
o
ac
h
p
r
o
v
id
es
b
etter
m
an
a
g
ed
s
er
v
ice
s
f
o
r
cu
s
to
m
er
s
w
a
n
ti
n
g
to
o
u
ts
o
u
r
ce
t
h
eir
i
n
f
o
r
m
atio
n
s
e
cu
r
it
y
o
p
er
atio
n
s
to
attai
n
r
eli
ab
le,
tr
an
s
p
ar
en
t,
a
n
d
ef
f
icie
n
t
clo
u
d
s
ec
u
r
it
y
an
d
p
r
iv
ac
y
[
1
6
]
.
C
lo
u
d
co
m
p
u
ti
n
g
p
r
o
m
i
s
es
to
i
n
cr
ea
s
e
t
h
e
v
elo
cit
y
w
it
h
w
h
ich
ap
p
lic
atio
n
ar
e
d
ep
lo
y
ed
,
in
cr
ea
s
e
in
n
o
v
a
tio
n
an
d
lo
w
e
r
co
s
ts
.
C
lo
u
d
co
m
p
u
ti
n
g
i
n
c
o
r
p
o
r
ates
v
ir
tu
aliza
tio
n
,
o
n
d
e
m
an
d
d
ep
lo
y
m
e
n
t,
in
ter
n
e
t
d
eliv
er
y
o
f
s
er
v
ices
a
n
d
o
p
en
s
o
u
r
ce
s
o
f
t
w
ar
e
.
Fro
m
a
n
o
t
h
er
p
er
s
p
ec
tiv
e,
ev
er
y
t
h
in
g
is
n
e
w
b
ec
a
u
s
e
clo
u
d
co
m
p
u
ti
n
g
ch
a
n
g
es
h
o
w
w
e
i
n
v
en
t,
d
ev
elo
p
,
d
ep
lo
y
,
s
ca
le,
u
p
d
ate,
m
ai
n
tai
n
an
d
p
ay
f
o
r
ap
p
licatio
n
an
d
th
e
i
n
f
r
a
s
tr
u
ct
u
r
e
o
n
w
h
ich
th
e
y
r
u
n
.
B
ec
au
s
e
o
f
th
e
s
e
b
en
ef
i
ts
o
f
clo
u
d
co
m
p
u
ti
n
g
,
it
r
eq
u
ir
e
s
an
ef
f
ec
tiv
e
an
d
f
le
x
ib
le
d
y
n
a
m
i
c
s
ec
u
r
i
t
y
s
c
h
e
m
e
to
e
n
s
u
r
e
t
h
e
co
r
r
ec
tn
es
s
o
f
u
s
er
s
’
d
ata
i
n
t
h
e
clo
u
d
.
Qu
a
lit
y
of
s
er
v
ice
i
s
an
i
m
p
o
r
tan
t a
s
p
e
ct
an
d
h
en
ce
,
e
x
te
n
s
i
v
e
clo
u
d
d
ata
s
ec
u
r
it
y
a
n
d
p
er
f
o
r
m
a
n
ce
is
r
eq
u
ir
ed
[
1
7
]
.
3.
P
RO
P
O
SE
D
WO
RK
I
n
o
r
d
er
to
p
r
o
tect
u
s
er
’
s
p
r
iv
ac
y
i
n
p
u
b
lic
clo
u
d
,
w
e
p
r
o
p
o
s
e
a
m
ig
r
atio
n
b
ased
ap
p
r
o
ac
h
w
h
ic
h
g
en
er
ate
s
t
h
e
V
M
p
lace
m
e
n
t
s
s
tr
ate
g
y
b
ased
o
n
s
ec
u
r
it
y
ev
alu
atio
n
o
f
ea
ch
VM
.
T
o
ev
al
u
ate
t
h
e
s
ec
u
r
i
t
y
o
f
ea
ch
VM
,
w
e
d
ep
lo
y
Dis
cr
et
e
T
im
e
Ma
r
k
o
v
C
h
ai
n
(
DT
MC)
an
d
p
r
ed
ict
th
e
p
o
s
s
ib
ilit
y
o
f
ea
ch
VM
b
ein
g
co
m
p
r
o
m
is
ed
.
T
h
en
a
p
lace
m
en
t
s
tr
ateg
y
w
il
l
b
e
p
r
o
d
u
ce
d
b
ased
o
n
s
ec
u
r
it
y
e
v
al
u
atio
n
.
Af
ter
VM
s
m
i
g
r
atio
n
,
u
s
er
s
’
VM
s
w
ill
s
u
r
v
iv
e
b
ef
o
r
e
t
h
e
attac
k
co
m
p
l
etes.
Me
a
n
w
h
ile,
o
u
r
ap
p
r
o
ac
h
al
s
o
co
n
s
id
er
s
t
h
e
p
er
f
o
r
m
a
n
ce
o
v
er
h
ea
d
b
ec
au
s
e
th
e
clo
s
er
co
n
n
ec
ted
VM
s
ar
e
p
lace
d
,
th
e
b
etter
p
er
f
o
r
m
a
n
ce
th
e
clo
u
d
p
latf
o
r
m
w
ill
ac
q
u
ir
e.
T
o
th
e
b
est
o
f
o
u
r
k
n
o
w
led
g
e,
th
is
ap
p
r
o
ac
h
is
th
e
f
ir
s
t
e
f
f
o
r
t
to
d
e
v
elo
p
th
e
f
o
llo
w
i
n
g
m
ec
h
a
n
i
s
m
s
a
n
d
tech
n
iq
u
e
s
t
o
en
h
a
n
ce
clo
u
d
s
ec
u
r
it
y
t
h
r
o
u
g
h
c
h
an
g
i
n
g
clo
u
d
p
lace
m
e
n
t.
T
h
e
co
n
tr
ib
u
tio
n
o
f
m
y
m
ig
r
atio
n
-
b
ased
p
lace
m
en
t stra
te
g
y
i
s
as b
elo
w
:
1
.
W
e
p
r
esen
t
a
s
y
s
te
m
atic
a
p
p
r
o
ac
h
to
p
r
ed
ict
th
e
p
o
s
s
ib
ilit
y
o
f
VM
o
n
ea
c
h
attac
k
s
t
ep
,
an
d
th
e
n
m
o
v
e
a
w
a
y
th
e
VM
s
b
ef
o
r
e
attac
k
s
u
cc
ee
d
s
.
2
.
W
e
p
r
o
p
o
s
e
an
alg
o
r
ith
m
to
g
en
er
ate
a
s
ec
u
r
e
p
lace
m
e
n
t
p
lan
w
h
ic
h
also
tak
e
s
p
er
f
o
r
m
a
n
ce
co
s
t
i
n
to
co
n
s
id
er
atio
n
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
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&
C
o
m
p
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n
g
I
SS
N:
2088
-
8708
Mig
r
a
tio
n
o
f V
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tu
a
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ch
in
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to
imp
r
o
ve
th
e
S
ec
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ity
in
C
lo
u
d
C
o
mp
u
tin
g
(
N
.
C
h
a
n
d
r
a
ka
la
)
213
3
.
T
h
e
ev
alu
at
io
n
r
es
u
lt
s
i
n
a
r
ea
l
p
u
b
lic
clo
u
d
s
h
o
w
m
y
ap
p
r
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ac
h
ca
n
g
r
ea
tl
y
i
m
p
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o
v
e
t
h
e
s
ec
u
r
it
y
o
f
en
tire
clo
u
d
p
latf
o
r
m
.
I
n
o
r
d
er
to
ac
cu
r
atel
y
es
ti
m
a
te
th
e
cu
r
r
e
n
t
n
et
w
o
r
k
s
ec
u
r
i
t
y
s
it
u
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an
a
w
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s
s
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d
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o
d
f
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w
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r
k
r
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p
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.
T
h
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h
r
ea
ts
an
d
p
r
ed
icts
s
u
b
s
eq
u
e
n
t
t
h
r
ea
ts
b
y
m
o
d
eli
n
g
attac
k
s
ce
n
ar
io
.
T
h
e
th
r
ea
t
a
w
ar
en
e
s
s
m
o
d
el
is
co
n
s
tr
u
cted
w
it
h
ex
p
an
d
ed
f
in
i
te
-
s
tate
au
to
m
at
a,
w
h
ic
h
i
s
d
e
f
i
n
ed
as
attac
k
s
tate
tr
a
n
s
it
io
n
g
r
ap
h
an
d
i
s
s
h
o
w
n
in
Fi
g
u
r
e
2
.
B
ased
o
n
th
e
f
o
r
m
er
all
p
o
s
s
ib
le
in
tr
u
d
in
g
p
ath
s
a
n
d
s
tate
tr
an
s
f
o
r
m
atio
n
ca
n
b
e
illu
s
tr
at
ed
,
an
d
b
ased
o
n
th
e
latter
r
ea
ll
y
h
ap
p
en
in
g
t
h
r
ea
ts
an
d
i
n
tr
u
d
i
n
g
p
at
h
ar
e
d
escr
ib
ed
.
T
h
en
a
th
r
ea
t
a
w
ar
en
es
s
alg
o
r
it
h
m
i
s
p
r
esen
ted
b
ased
o
n
th
e
ab
o
v
e
m
o
d
el.
W
i
t
h
th
i
s
al
g
o
r
ith
m
,
v
ar
io
u
s
k
in
d
s
o
f
in
v
alid
th
r
ea
t
s
ar
e
f
ilter
ed
;
c
u
r
r
en
t
v
alid
th
r
ea
t
s
ar
e
o
b
tain
ed
b
y
c
o
r
r
elatin
g
d
y
n
a
m
ic
alar
m
s
w
it
h
s
tatic
at
tack
s
ce
n
ar
io
.
Fig
u
r
e
2.
A
ttac
k
s
s
tate
tr
an
s
iti
o
n
g
r
ap
h
Gen
er
all
y
,
t
h
e
ad
v
er
s
ar
ies
s
h
o
u
ld
tak
e
s
ev
er
al
s
tep
s
to
co
m
p
r
o
m
i
s
e
a
VM
.
A
s
s
h
o
w
n
i
n
att
ac
k
s
s
tate
tr
an
s
itio
n
g
r
ap
h
(
F
ig
u
r
e
2
)
,
t
h
e
ad
v
er
s
ar
y
s
tar
ts
f
r
o
m
co
m
p
r
o
m
i
s
in
g
o
n
e
VM
o
n
a
n
e
w
s
er
v
er
(
S
0
)
.
Af
ter
h
y
p
er
v
is
o
r
is
co
m
p
r
o
m
i
s
ed
(
S
1
)
,
th
e
ad
v
er
s
ar
y
w
ill
co
llec
t
d
ep
en
d
en
c
y
i
n
f
o
r
m
atio
n
o
f
co
m
p
r
o
m
is
ed
VM
s
(
S
2
)
.
Fin
al
l
y
,
n
e
w
tar
g
et
s
er
v
e
r
w
i
ll b
e
s
elec
ted
(
S
3
)
.
W
e
m
a
k
e
th
e
f
o
llo
w
i
n
g
as
s
u
m
p
tio
n
s
o
n
clo
u
d
ad
v
er
s
ar
ies
w
h
o
w
an
t to
co
m
p
r
o
m
i
s
e
th
e
VM
s
an
d
u
s
er
s
p
r
iv
ac
y
.
1
.
T
h
e
clo
u
d
ad
v
er
s
ar
ies ca
n
d
etec
t th
e
v
u
l
n
er
ab
ilit
ie
s
o
f
b
o
th
clo
u
d
p
latf
o
r
m
a
n
d
v
ir
t
u
al
m
ac
h
in
e
s
.
2
.
T
h
e
clo
u
d
ad
v
er
s
ar
ies
w
ill
f
o
llo
w
th
e
at
tack
tr
a
n
s
it
io
n
g
r
a
p
h
to
co
m
p
r
o
m
i
s
e
a
VM
s
tep
b
y
s
tep
.
3
.
T
h
e
clo
u
d
ad
v
er
s
ar
ies al
w
a
y
s
c
h
o
o
s
e
th
e
ea
s
ie
s
t ta
r
g
e
t
in
ter
m
o
f
t
h
e
v
u
l
n
er
ab
ilit
ies.
4
.
T
h
e
attac
k
er
h
as
n
o
v
ie
w
o
f
t
h
e
clo
u
d
v
ie
w
at
th
e
b
eg
i
n
n
i
n
g
o
f
t
h
e
at
tack
s
.
Ho
w
e
v
e
r
,
th
e
attac
k
er
m
a
y
ac
q
u
ir
e
m
o
r
e
k
n
o
w
led
g
e
af
ter
co
m
p
r
o
m
is
i
n
g
m
o
r
e
n
o
d
es in
t
h
e
clo
u
d
.
I
f
t
h
e
clo
u
d
p
r
o
v
id
er
ca
n
m
i
g
r
ate
VM
s
to
a
s
a
f
e
n
o
d
e
b
ef
o
r
e
th
e
n
o
d
e
is
co
m
p
r
o
m
is
e
d
,
m
ig
r
ate
d
VM
s
w
ill s
u
r
v
iv
e
t
h
i
s
attac
k
.
W
e
s
et
u
p
th
e
f
o
llo
w
i
n
g
g
o
al
s
w
h
e
n
d
esig
n
t
h
e
p
lace
m
e
n
t a
l
g
o
r
ith
m
.
1
.
R
ed
u
ce
th
e
n
u
m
b
er
o
f
co
m
p
r
o
m
i
s
ed
VM
s
.
2
.
I
n
cr
ea
s
e
th
e
s
u
r
v
i
v
ab
ilit
y
o
f
s
er
v
ices.
3
.
T
h
e
p
lace
m
e
n
t a
l
g
o
r
ith
m
is
also
co
m
p
atib
le
w
ith
p
er
f
o
r
m
a
n
ce
r
eq
u
ir
e
m
e
n
t
s
.
I
n
o
r
d
er
to
v
er
if
y
th
e
i
m
p
r
o
v
e
m
en
t
o
f
s
u
r
v
i
v
ab
ilit
y
a
f
ter
m
i
g
r
atio
n
,
w
e
d
ef
in
e
t
h
e
s
u
r
v
i
v
a
b
ilit
y
o
f
a
s
er
v
ice
i
n
T
h
eo
r
em
1
.
T
h
en
w
e
n
ee
d
to
ev
alu
ate
t
h
e
s
u
r
v
i
v
ab
i
lit
y
o
f
a
n
o
d
e
as sh
o
w
n
in
T
h
e
o
r
em
2
.
T
h
eo
r
em
1
: Su
r
v
i
v
ab
ilit
y
o
f
a
Ser
v
ice
Giv
e
n
a
s
er
v
ice
S
i
(
VM
ch
ai
n
)
in
clu
d
i
n
g
s
o
m
e
r
elate
d
Si =
{
VM
a
,
VM
b
,
…….
,
VM
n
}
an
d
n
o
d
e
s
et
N
=
{N
1
, N
2
,
…,
N
m
},
I
f
th
e
s
u
r
v
iv
ab
ili
t
y
i
n
s
p
ec
i
f
ic
attac
k
s
tep
f
o
r
th
e
No
d
es
w
h
ic
h
h
o
ld
th
e
VM
b
elo
n
g
to
S
i
=
{P
N
1
,
P
N
2
,
….
,
P
N
m
},
T
h
en
,
Su
r
v
iv
ab
ili
t
y
(
P
S)
f
o
r
s
er
v
ice
S
i
is
b
elo
w
:
(
1
)
T
h
eo
r
em
2
: Su
r
v
i
v
ab
ilit
y
o
f
a
No
d
e
Giv
e
n
a
n
o
d
e
N
an
d
a
s
et
o
f
V
M
s
={
VM
a
,
VM
b
,
…….
,
VM
n
}
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
8
,
No
.
1
,
Feb
r
u
ar
y
201
8
:
2
1
0
–
2
1
9
214
w
h
ic
h
lo
ca
te
at
n
o
d
e
N,
an
d
th
e
co
m
p
r
o
m
i
s
ed
p
r
o
b
ab
il
it
y
f
o
r
th
e
s
e
VM
s
ar
e
{P
a
,
P
b
,
….
,
P
m
},
th
e
s
u
r
v
iv
ab
ili
t
y
(
P
N)
f
o
r
No
d
e
N
is
b
elo
w
:
(
2
)
4
.
CL
O
UD
M
I
G
RA
T
I
O
N
B
AS
E
D
ARCH
I
T
E
CT
URE
Dev
elo
p
in
g
a
clo
u
d
m
i
g
r
ati
o
n
s
tr
ateg
y
r
eq
u
ir
es
u
n
d
er
s
t
an
d
in
g
b
e
y
o
n
d
w
h
at
'
s
i
n
th
e
v
en
d
o
r
b
r
o
ch
u
r
es.
Yo
u
n
ee
d
to
u
n
d
er
s
tan
d
th
e
ar
ch
itect
u
r
e
o
f
th
a
t
e
n
v
ir
o
n
m
e
n
t.
Yo
u
n
ee
d
to
u
n
d
er
s
tan
d
th
e
p
o
ten
tia
l
r
is
k
s
an
d
th
e
p
o
ten
tial
h
ar
m
t
o
y
o
u
r
o
r
g
a
n
izatio
n
f
r
o
m
e
x
p
o
s
in
g
it
to
th
o
s
e
r
is
k
s
.
T
h
at
in
f
l
u
en
ce
s
y
o
u
r
ab
ilit
y
to
p
r
o
p
er
ly
ass
e
s
s
a
g
i
v
e
n
clo
u
d
an
d
it
e
m
p
o
w
er
s
y
o
u
to
f
o
r
m
cr
i
ter
ia
an
d
th
e
n
d
eter
m
in
e
w
h
at
t
y
p
e
o
f
clo
u
d
en
v
ir
o
n
m
e
n
t
y
o
u
r
o
r
g
a
n
izati
o
n
n
ee
d
s
a
n
d
ag
ai
n
to
w
h
at
ex
te
n
t
y
o
u
s
h
o
u
ld
b
e
ad
o
p
tin
g
clo
u
d
-
b
ased
I
T
r
eso
u
r
ce
s
.
T
h
e
s
tr
u
ctu
r
e
o
f
m
i
g
r
atio
n
-
b
ased
ap
p
r
o
ac
h
is
s
h
o
w
n
in
Fi
g
u
r
e
3
.
I
n
o
r
d
er
to
ac
co
m
p
li
s
h
th
e
d
esi
g
n
g
o
al,
m
y
ap
p
r
o
ac
h
in
cl
u
d
es
th
r
ee
co
m
p
o
n
e
n
ts
:
s
ec
u
r
it
y
e
v
alu
a
tio
n
,
s
tr
ate
g
y
g
e
n
er
atio
n
,
an
d
p
er
f
o
r
m
a
n
ce
ev
alu
a
tio
n
.
Firs
t
o
f
all,
t
h
e
d
ep
en
d
en
c
y
e
x
p
lo
r
atio
n
m
ec
h
a
n
is
m
d
etec
t
s
th
e
s
er
v
ice
d
ep
en
d
en
cies
a
m
o
n
g
VM
s
th
r
o
u
g
h
n
et
w
o
r
k
co
n
n
ec
tio
n
s
.
W
e
ev
al
u
ate
ea
c
h
VM
’
s
s
ec
u
r
it
y
lev
el
ac
co
r
d
in
g
to
t
h
e
v
u
ln
er
ab
ilit
ies
f
o
u
n
d
i
n
VM
’
s
o
p
er
atin
g
s
y
s
te
m
.
Af
ter
w
ar
d
s
,
w
e
u
tili
ze
DT
MC
to
e
x
p
ec
t
t
h
e
p
o
s
s
ib
il
it
y
o
f
s
u
cc
es
s
f
u
l
a
ttack
s
i
n
ea
c
h
attac
k
s
tep
.
Fi
n
all
y
,
w
e
d
es
ig
n
an
alg
o
r
it
h
m
to
cr
ea
te
th
e
p
lace
m
en
t
p
lan
w
h
ic
h
t
ak
es
s
ec
u
r
it
y
a
n
d
p
er
f
o
r
m
a
n
ce
i
n
to
co
n
s
id
er
atio
n
.
Fig
u
r
e
3
.
C
lo
u
d
m
i
g
r
atio
n
b
as
ed
ar
ch
itectu
r
e
Th
er
e
ar
e
th
r
ee
co
m
m
o
n
c
ateg
o
r
ies
f
o
r
ap
p
r
o
ac
h
in
g
c
lo
u
d
m
i
g
r
atio
n
:
Ma
c
h
in
e
to
m
ac
h
i
n
e,
ap
p
licatio
n
m
i
g
r
atio
n
s
,
a
n
d
Dev
Op
s
d
r
iv
e
n
m
i
g
r
atio
n
s
.
I
n
all
th
r
ee
ca
teg
o
r
ies
y
o
u
ca
n
m
o
v
e
ev
er
y
t
h
i
n
g
,
o
r
y
o
u
ca
n
f
o
c
u
s
o
n
m
o
v
in
g
ce
r
tain
w
o
r
k
lo
ad
s
a
n
d
tak
e
a
h
y
b
r
id
ap
p
r
o
ac
h
.
Selectin
g
th
e
w
o
r
k
lo
ad
s
to
m
o
v
e
m
a
y
b
e
b
ased
o
n
r
ef
r
esh
c
y
cles,
n
e
w
p
r
o
j
ec
ts
o
r
to
g
ain
ex
p
er
ien
ce
a
n
d
co
n
f
id
e
n
ce
in
a
clo
ud
-
ba
s
ed
a
rc
hite
ct
ure
.
L
et
’
s
s
tar
t
w
i
th
th
e
s
i
m
p
le
s
t
s
tr
ateg
y
:
m
ac
h
i
n
e
to
m
ac
h
i
n
e
m
i
g
r
atio
n
s
.
M
ac
h
in
e
to
m
ac
h
i
n
e
m
i
g
r
atio
n
i
n
v
o
l
v
es
m
o
v
i
n
g
v
i
r
tu
al
m
ac
h
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s
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m
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m
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is
th
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lest
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ar
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e,
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icie
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h
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o
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h
as a
r
eq
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ir
e
m
en
t
f
o
r
a
m
o
r
e
r
ap
id
m
i
g
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.
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h
e
s
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o
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d
co
m
m
o
n
t
y
p
e
o
f
m
ig
r
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is
ap
p
licatio
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m
ig
r
atio
n
.
T
h
is
i
n
v
o
l
v
es
b
u
ild
in
g
f
r
es
h
in
f
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ct
u
r
e
i
n
t
h
e
c
lo
u
d
s
u
ch
as
s
er
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er
s
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s
to
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d
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et
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tall
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h
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eg
ac
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licatio
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s
,
f
o
llo
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ed
b
y
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d
ata
m
ig
r
atio
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ex
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cise.
T
h
e
n
o
t
ab
le
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en
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it
co
m
p
ar
ed
to
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lif
t
an
d
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h
i
f
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ap
p
r
o
ac
h
is
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at
it
allo
w
s
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r
r
e
-
ar
c
h
itect
u
r
e,
wh
ile
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r
o
v
id
in
g
b
etter
o
p
er
atio
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al
ef
f
icie
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s
.
C
o
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to
a
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h
i
f
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m
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g
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h
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w
ith
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p
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iate
p
lan
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g
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d
d
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v
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y
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T
h
e
th
ir
d
a
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d
f
in
al
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e
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f
m
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g
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De
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A
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Mi
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ess
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ll
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Op
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n
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ig
r
atio
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e
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ca
p
ab
ilit
y
to
h
av
e
C
o
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ti
n
u
o
u
s
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te
g
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(
C
I
)
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d
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n
tin
u
o
u
s
d
eli
v
er
y
(
C
D)
,
allo
w
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u
to
f
i
x
b
u
g
s
a
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d
p
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id
e
n
e
w
f
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r
es
s
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er
.
I
t
also
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2088
-
8708
Mig
r
a
tio
n
o
f V
ir
tu
a
l Ma
ch
in
e
to
imp
r
o
ve
th
e
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ity
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mp
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tin
g
(
N
.
C
h
a
n
d
r
a
ka
la
)
215
p
r
o
v
id
es
an
o
p
p
o
r
tu
n
it
y
to
r
e
-
alig
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tech
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h
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b
u
s
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ess
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ir
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m
e
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s
o
f
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e
o
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g
an
izatio
n
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A
De
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ater
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elo
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m
.
On
e
o
f
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h
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m
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co
m
m
o
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l
y
cited
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aso
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a
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m
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ch
a
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g
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d
ir
ec
tio
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ic
k
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ier
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ick
in
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clo
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a
n
d
w
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at
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to
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in
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r
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ar
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f
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i
d
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atio
n
o
f
t
h
ese
f
ac
to
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s
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co
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p
led
w
ith
p
lan
n
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g
a
n
d
d
is
co
v
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y
ca
n
h
e
lp
a
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s
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ess
m
a
x
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eg
i
n
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alizin
g
th
e
b
e
n
ef
i
ts
s
o
o
n
er
.
5.
E
XP
E
R
I
M
E
NT
A
L
RE
SUL
T
S AN
A
L
YS
I
S
I
n
o
r
d
er
to
q
u
an
ti
f
y
t
h
e
v
u
l
n
e
r
ab
ilit
y
,
w
e
f
ir
s
t
l
y
s
ca
n
t
h
e
g
u
est
VM
s
a
n
d
d
etec
t
t
h
e
v
u
l
n
er
ab
ilit
ies
m
atc
h
ed
in
n
atio
n
al
v
u
l
n
er
ab
ilit
y
d
atab
ase
(
NVD)
.
Af
te
r
w
ar
d
s
,
d
is
cr
ete
ti
m
e
Ma
r
k
o
v
a
ch
ai
n
an
al
y
s
i
s
(
DT
MC)
w
ill
p
r
ed
ict
th
e
p
o
s
s
ib
ilit
y
o
f
s
u
cc
e
s
s
f
u
l
attac
k
s
i
n
ea
ch
s
tep
.
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o
m
m
o
n
v
u
ln
er
ab
ilit
y
s
co
r
in
g
s
y
s
te
m
(
C
VSS)
p
r
o
v
id
es
a
f
r
a
m
e
wo
r
k
to
s
ca
n
t
h
e
g
u
est
VM
an
d
s
co
r
e
s
ec
u
r
it
y
o
f
g
u
e
s
t
VM
s
b
ased
o
n
v
u
l
n
er
ab
ilit
ie
s
.
T
h
er
e
ar
e
th
r
e
e
m
etr
ics
g
r
o
u
p
i
n
C
VS
S
s
y
s
te
m
:
b
a
s
e,
te
m
p
o
r
al,
an
d
e
n
v
ir
o
n
m
e
n
t.
E
ac
h
o
f
th
e
m
ca
n
r
ep
r
esen
t d
i
f
f
er
en
t c
h
ar
ac
ter
s
o
f
v
u
l
n
er
ab
ilit
ie
s
.
5
.
1
.
M
a
rk
o
v
Cha
in Ana
ly
s
is
I
n
o
r
d
er
to
r
ep
r
esen
t
th
e
at
ta
ck
p
ath
an
d
p
o
s
s
ib
il
it
y
o
f
s
u
c
ce
s
s
f
u
l
attac
k
i
n
ea
ch
s
tep
,
we
w
ill
u
s
e
attac
k
d
ep
en
d
en
c
y
g
r
ap
h
(
A
D
G
)
b
ased
o
n
Ma
r
k
o
v
c
h
ai
n
An
al
y
s
i
s
as
s
h
o
w
n
i
n
Fi
g
u
r
e
4
.
T
h
e
p
r
o
ce
d
u
r
e
o
f
DT
MC p
r
ed
ictio
n
is
ex
p
lain
ed
as f
o
llo
w
s
:
(
a)
Step
1
(
b
)
Step
2
Fig
u
r
e
4
.
A
ttac
k
d
ep
en
d
en
c
y
g
r
ap
h
b
ased
o
n
Ma
r
k
o
v
c
h
ai
n
an
al
y
s
is
Fo
r
n
n
o
d
es in
A
D
G
g
r
ap
h
,
as
s
u
m
e
t
h
e
in
i
tial p
r
o
b
ab
ilit
y
d
is
tr
ib
u
tio
n
o
n
ea
c
h
n
o
d
e
is
,
1
.
T
h
e
in
itial
is
d
eter
m
in
ed
b
y
attac
k
er
’
s
f
ir
s
t c
h
o
ice.
2
.
I
n
attac
k
s
tep
1
,
th
e
p
o
s
s
ib
il
it
y
d
is
tr
ib
u
tio
n
o
f
at
tack
er
ca
n
co
m
p
r
o
m
i
s
e
co
n
n
ec
ted
VM
’
s
is
,
3
.
A
f
ter
k
th
s
tep
attac
k
,
th
e
p
o
s
s
ib
ilit
y
d
i
s
tr
ib
u
tio
n
w
ill b
ec
o
m
e,
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
8
,
No
.
1
,
Feb
r
u
ar
y
201
8
:
2
1
0
–
2
1
9
216
W
h
er
e
P
is
th
e
s
ta
te
-
tr
a
n
s
i
tio
n
p
r
o
b
ab
ilit
y
m
atr
i
x
o
f
DT
MC a
n
d
Fo
r
ex
a
m
p
le,
Fig
u
r
e
4
(
b
)
:
s
tep
2
is
u
s
ed
as
an
ex
a
m
p
le
to
ex
p
lain
h
o
w
DT
MC
p
r
ed
ict
th
e
attac
k
p
o
s
s
ib
ilit
y
in
ea
ch
s
tep
.
I
ass
u
m
e
t
h
at
t
h
e
f
ir
s
t c
o
m
p
r
o
m
is
ed
VM
s
h
o
u
ld
b
e
VM
2
,
Hen
ce
,
Hen
ce
w
e
m
a
y
o
b
tai
n
t
h
e
atta
ck
p
o
s
s
ib
ilit
y
f
r
o
m
ab
o
v
e
as
s
u
m
p
tio
n
.
Fo
r
ex
a
m
p
le,
t
h
e
ed
g
e
f
r
o
m
VM
3
to
VM
7
is
0
.
9
,
w
h
ic
h
i
n
d
icate
s
th
a
t
a
f
ter
VM
3
is
co
m
p
r
o
m
i
s
ed
,
VM
7
w
ill
h
a
v
e
9
0
%
c
h
an
ce
s
to
b
e
tak
e
n
o
v
er
b
y
t
h
e
attac
k
er
.
T
h
e
co
r
r
esp
o
n
d
in
g
s
tate
-
tr
an
s
i
tio
n
p
r
o
b
ab
ilit
y
m
atr
i
x
P
is
as f
o
llo
w
s
.
(
3
)
Fo
r
Step
1
,
w
e
g
et
th
e
p
o
s
s
ib
il
it
y
o
f
b
ei
n
g
co
m
p
r
o
m
is
ed
f
o
r
ea
ch
VM
is
,
B
ased
o
n
th
e
r
esu
lt,
VM
5
is
t
h
e
m
o
s
t
d
a
n
g
er
o
u
s
VM
,
a
n
d
th
en
w
e
r
e
m
o
v
e
t
h
e
ed
g
es
wh
ich
p
o
in
t
to
VM
5
b
ec
au
s
e
th
e
at
tack
er
w
ill
n
o
t c
o
m
p
r
o
m
is
e
VM
5
a
g
ai
n
in
t
h
e
f
o
llo
w
i
n
g
attac
k
p
ath
.
Hen
ce
,
th
e
r
es
u
lt o
f
m
atr
i
x
af
t
er
s
tep
o
n
e
s
h
o
u
ld
b
e
as f
o
llo
w
s
a
n
d
th
e
D
AG
s
h
o
u
ld
b
e:
(
4
)
Ma
r
k
o
v
ch
ai
n
a
n
al
y
s
is
w
ill en
d
if
th
e
s
tep
r
ea
ch
e
s
th
e
lo
n
g
e
s
t p
ath
in
a
n
A
DG.
Hen
ce
,
th
e
p
r
o
b
ab
ilit
y
d
is
tr
ib
u
tio
n
f
o
r
th
e
i
n
itia
l state
a
n
d
th
e
f
ir
s
t 6
s
tep
s
ar
e
as
f
o
llo
w
s
.
(
5
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2088
-
8708
Mig
r
a
tio
n
o
f V
ir
tu
a
l Ma
ch
in
e
to
imp
r
o
ve
th
e
S
ec
u
r
ity
in
C
lo
u
d
C
o
mp
u
tin
g
(
N
.
C
h
a
n
d
r
a
ka
la
)
217
W
h
er
e
is
th
e
p
r
o
b
ab
ilit
y
d
is
tr
ib
u
tio
n
in
s
tep
k
.
I
n
th
e
ab
o
v
e
ex
a
m
p
le,
ac
co
r
d
in
g
to
,
in
th
e
4
th
s
tep
,
th
e
p
r
o
b
a
b
ilit
y
th
at
VM
2
i
s
co
m
p
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m
i
s
ed
w
ill
b
e
2
.
6
%
an
d
th
e
p
r
o
b
ab
ilit
y
t
h
at
VM
7
is
co
m
p
r
o
m
is
ed
w
ill
b
e
41
.
4
%.
5
.
2
.
P
la
ce
m
ent
G
ener
a
t
io
n St
ra
t
eg
y
B
ased
o
n
th
e
p
lace
m
e
n
t
s
tr
at
eg
y
g
en
er
atio
n
alg
o
r
it
h
m
s
h
o
w
n
in
T
ab
le
1
,
w
e
h
a
v
e
ac
q
u
ir
ed
th
e
p
o
s
s
ib
ilit
y
o
f
b
ein
g
at
tack
ed
f
o
r
ea
ch
VM
.
Nex
t,
w
e
w
ill
d
e
s
ig
n
a
p
lace
m
en
t
s
tr
ate
g
y
to
r
ea
llo
ca
te
g
u
est
V
Ms
b
ef
o
r
e
th
e
attac
k
s
u
cc
ee
d
s
.
T
h
e
p
r
in
cip
le
o
f
n
e
w
s
tr
ateg
y
i
s
is
o
lati
n
g
th
e
VM
s
w
i
th
h
i
g
h
s
ec
u
r
it
y
r
is
k
s
f
r
o
m
VM
s
w
it
h
lo
w
s
ec
u
r
it
y
.
I
n
o
r
d
er
to
r
ed
u
ce
th
e
p
er
f
o
r
m
a
n
c
e
o
v
er
h
ea
d
,
co
n
n
ec
ted
VM
s
w
it
h
s
i
m
ilar
s
ec
u
r
it
y
r
is
k
w
ill
b
e
ass
ig
n
ed
i
n
th
e
s
a
m
e
n
o
d
e.
W
h
e
n
d
esi
g
n
t
h
e
p
la
ce
m
en
t
al
g
o
r
ith
m
,
w
e
as
s
u
m
e
th
e
n
o
d
e
w
ill
h
a
v
e
en
o
u
g
h
r
eso
u
r
ce
s
ca
p
ac
it
y
(
e.
g
.
C
P
U,
m
e
m
o
r
y
a
n
d
d
is
k
s
e
tc.
)
to
h
o
ld
all
g
u
es
t
VM
s
.
I
n
ea
ch
attac
k
s
tep
,
DT
MC
an
d
C
VSS
w
ill
p
r
ed
ict
th
e
attac
k
p
o
s
s
ib
ilit
y
f
o
r
ea
ch
VM
.
T
h
e
alg
o
r
ith
m
w
ill
s
o
r
t
th
e
p
o
s
s
ib
ilit
y
an
d
f
i
n
d
th
e
m
o
s
t
“
d
an
g
er
o
u
s
”
V
M
w
h
ic
h
i
s
m
o
s
t
l
ik
el
y
to
b
e
co
m
p
r
o
m
is
ed
.
T
h
e
alg
o
r
it
h
m
w
il
l
as
s
i
g
n
th
e
m
o
s
t
d
an
g
er
o
u
s
VM
to
a
d
ed
icate
d
n
o
d
e
an
d
allo
ca
te
o
th
er
VM
s
to
d
if
f
er
en
t
n
o
d
e.
T
h
er
ef
o
r
e,
ev
en
if
th
e
m
o
s
t
d
an
g
er
o
u
s
VM
is
co
m
p
r
o
m
i
s
e
d
,
o
th
er
VM
w
ill
n
o
t
b
e
ex
p
lo
ited
b
y
t
h
e
attac
k
er
.
W
h
e
n
m
i
g
r
atin
g
a
VM
,
th
e
VM
is
u
s
u
all
y
s
h
u
t o
f
f
f
ir
s
t,
h
en
ce
,
m
i
g
r
atio
n
ti
m
e
is
o
n
e
o
f
th
e
m
o
s
t si
g
n
i
f
ican
t f
ac
to
r
s
w
e
s
h
o
u
ld
co
n
s
id
er
i
n
o
r
d
er
to
im
p
r
o
v
e
t
h
e
s
y
s
te
m
p
er
f
o
r
m
a
n
ce
.
I
n
o
r
d
er
to
test
th
e
o
v
er
h
ea
d
o
n
V
Ms
m
i
g
r
a
tio
n
,
w
e
d
esi
g
n
an
ev
alu
a
tio
n
o
n
t
h
e
p
latf
o
r
m
s
p
e
cif
ied
as
T
ab
le
1
.
T
ab
le
1
.
A
lg
o
r
ith
m
: P
lace
m
e
n
t stra
teg
y
g
e
n
er
atio
n
al
g
o
r
ith
m
R
eq
u
ir
e:
1.
Vir
tu
al
m
ac
h
in
e
s
e
t
V
=
{V
1
, V
2
,…,V
n
)
Dep
en
d
en
t V
M
s
s
et
f
o
r
ea
ch
VM
s
et
Dep
en
d
en
t V
Ms
,
w
h
er
e
d
ep
en
d
en
t V
M
i
is
th
e
s
et
w
h
ic
h
r
ep
r
esen
ts
t
h
e
2.
Dep
en
d
en
t V
M
s
f
o
r
V
Mi
(
i ≤
n
)
3.
T
h
e
P
h
y
s
ical
m
ac
h
i
n
e
(
No
d
e)
s
et
N
=
{N
1
, N
2
, …, N
k
}
4.
T
h
e
co
m
p
r
o
m
is
ed
p
o
s
s
ib
ili
t
y
f
o
r
ea
ch
VM
is
Pi
(
i ≤
n
)
E
n
s
u
r
e:
P
la
ce
men
t S
tr
a
teg
y
1
: So
r
t V
Ms in
asce
n
d
in
g
o
r
d
er
o
f
attac
k
p
o
s
s
ib
ilit
y
So
r
t
{V
1
,
V
2
,…,V
n
)
2
:
d
an
g
er
o
u
s
V
M
=
f
in
d
M
o
s
t
Dan
g
er
o
u
s
(
)
w
il
l
f
in
d
th
e
m
o
s
t
d
an
g
er
o
u
s
VM
i
n
d
ex
b
y
co
m
p
ar
i
n
g
co
m
p
r
o
m
is
ed
p
o
s
s
ib
ilit
y
o
f
V
Ms in
s
e
t V
3
:
d
a
n
g
ero
u
s
N
o
d
e
=
f
in
d
R
an
d
o
m
No
d
e
(
)
w
ill
f
i
n
d
a
r
an
d
o
m
n
o
d
e
to
s
to
r
e
th
e
d
an
g
er
o
u
s
VM
.
4
: M
ap
v
(
d
an
g
er
o
u
s
VM
,
d
an
g
er
o
u
s
No
d
e)
w
i
ll a
s
s
ig
n
d
an
g
er
o
u
s
VM
to
d
an
g
er
o
u
s
No
d
e
5
:
w
h
ile
!
V.
e
m
p
t
y
(
)
d
o
6:
n
o
d
e
=
f
in
d
R
a
n
d
o
m
No
d
e
(
)
w
ill r
etu
r
n
a
n
e
w
n
o
d
e
7:
n
ew V
M
=
V
.
p
o
p
(
)
f
in
d
a
s
af
e
VM
8
: M
ap
(
N
ewVM
,
node
)
ass
ig
n
n
e
w
VM
to
s
af
e
n
o
d
e
9
:
Ma
p
(
Dep
en
d
en
t n
ew V
M
,
node
)
ass
ig
n
t
h
e
co
n
n
ec
ted
VM
s
in
to
s
a
m
e
n
o
d
e.
1
0
: u
p
d
ate
V
1
1
: e
n
d
w
h
ile
5
.
3
.
Resul
t
A
na
ly
s
i
s
A
cc
o
r
d
in
g
to
o
u
r
ex
p
er
i
m
e
n
t
al
r
esu
lt
s
s
h
o
w
n
i
n
Fi
g
u
r
e
5
,
th
e
9
1
.
4
%
s
er
v
ices
o
b
tain
ed
i
m
p
r
o
v
ed
s
u
r
v
iv
ab
ili
t
y
.
T
h
e
m
a
x
i
m
u
m
s
u
r
v
iv
ab
ilit
y
e
n
h
a
n
ce
m
en
t
is
7
4
.
3
%
an
d
th
e
av
er
ag
e
i
m
p
r
o
v
e
m
e
n
t
o
f
s
u
r
v
iv
ab
ili
t
y
p
o
s
s
ib
il
it
y
i
s
2
7
.
2
%.
I
n
o
u
r
ex
p
er
i
m
en
t,
w
e
ca
n
f
i
n
d
th
er
e
ar
e
2
0
VM
s
w
ill
b
e
co
m
p
r
o
m
is
ed
at
attac
k
s
tep
1
i
n
r
a
n
d
o
m
p
lace
m
en
t
p
lan
.
Ho
w
e
v
er
,
in
o
u
r
n
e
w
p
lace
m
e
n
t
p
lan
,
t
h
e
n
u
m
b
er
o
f
co
m
p
r
o
m
is
ed
VM
s
is
o
n
l
y
4
.
Mo
r
eo
v
er
,
ac
c
o
r
d
in
g
to
o
u
r
s
tatis
tic
s
,
th
e
av
er
ag
e
co
m
p
r
o
m
is
ed
VM
n
u
m
b
er
is
4
in
o
u
r
p
lan
,
b
u
t in
r
an
d
o
m
p
lace
m
e
n
t,
th
i
s
av
er
ag
e
n
u
m
b
er
o
f
co
m
p
r
o
m
i
s
ed
VM
s
is
1
1
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
8
,
No
.
1
,
Feb
r
u
ar
y
201
8
:
2
1
0
–
2
1
9
218
Fig
u
r
e
5
.
C
o
m
p
ar
is
o
n
o
f
s
u
r
v
i
v
ab
ilit
y
6.
CO
NCLU
SI
O
N
C
lo
u
d
co
m
p
u
ti
n
g
i
s
q
u
ic
k
l
y
b
ec
o
m
in
g
m
o
r
e
a
n
d
m
o
r
e
i
m
p
o
r
tan
t
i
n
co
m
p
u
tin
g
i
n
f
r
astru
ct
u
r
es.
I
n
t
h
e
m
i
g
r
atio
n
-
b
ased
p
r
iv
ac
y
p
r
o
tectio
n
ap
p
r
o
ac
h
,
w
e
d
e
m
o
n
s
t
r
ated
th
at
th
e
p
lace
m
en
t
o
f
V
Ms
ca
n
m
a
k
e
h
u
g
e
d
if
f
er
e
n
ce
i
n
ter
m
s
o
f
s
ec
u
r
it
y
le
v
el
s
.
B
ased
o
n
s
u
r
v
i
v
ab
il
it
y
e
v
al
u
atio
n
o
f
VM
s
a
n
d
D
T
MC
an
al
y
s
i
s
,
w
e
d
ev
elo
p
ed
an
alg
o
r
ith
m
to
g
e
n
er
ate
a
s
af
e
p
lace
m
en
t
p
lan
t
h
at
m
o
v
es
t
h
e
g
u
es
t
VM
s
b
ef
o
r
e
attac
k
s
u
cc
ee
d
s
.
T
h
e
ex
p
er
i
m
en
tal
r
es
u
lt
s
s
h
o
w
th
at
o
u
r
al
g
o
r
ith
m
ca
n
s
i
g
n
if
ica
n
tl
y
i
m
p
r
o
v
e
t
h
e
s
u
r
v
i
v
a
b
ilit
y
o
f
VM
s
in
t
h
e
clo
u
d
an
d
r
ed
u
ce
th
e
n
u
m
b
e
r
o
f
co
m
p
r
o
m
i
s
ed
VM
s
i
n
ca
s
e
o
f
attac
k
s
.
T
h
e
o
v
er
h
ea
d
s
o
f
o
u
r
p
r
o
p
o
s
ed
ap
p
r
o
ac
h
ar
e
also
p
r
ac
tical.
I
n
m
a
n
y
ca
s
e
s
,
s
a
m
e
v
u
l
n
er
ab
ilit
ies
ca
n
r
u
n
o
n
d
i
f
f
er
e
n
t
V
Ms
w
h
ich
w
i
ll
ca
u
s
e
ad
v
er
s
ar
y
to
co
m
p
r
o
m
is
e
th
e
s
e
d
if
f
er
e
n
t
VM
s
s
i
m
u
lta
n
eo
u
s
l
y
.
B
ased
o
n
o
u
r
an
al
y
s
i
s
w
e
s
h
o
w
ed
th
at
o
u
r
p
r
o
p
o
s
ed
alg
o
r
ith
m
u
tili
ze
s
m
i
n
i
m
u
m
n
u
m
b
er
o
f
p
h
y
s
ica
l
s
er
v
er
s
f
o
r
h
o
s
ti
n
g
th
e
s
et
o
f
VM
s
,
w
h
ic
h
al
s
o
r
ed
u
ce
s
th
e
en
er
g
y
co
n
s
u
m
p
ti
o
n
o
f
th
e
d
atac
en
ter
an
d
it
ac
h
iev
ed
h
i
g
h
r
eso
u
r
ce
u
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T
h
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s
Risten
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y
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[2
]
M
o
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a
m
m
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d
A
.
A
lZ
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in
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Be
n
S
o
h
,
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c
P
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rd
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e
,
“
T
M
R
-
M
CDB:
En
h
a
n
c
in
g
S
e
c
u
rit
y
in
a
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u
lt
i
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c
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o
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t
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p
e
n
d
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li
ty
,
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ter
n
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ti
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l
jo
u
rn
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lo
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d
c
o
m
p
u
t
in
g
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n
d
se
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s
s
c
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e
(
IJ
-
CL
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ER
)
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3
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3
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n
e
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0
1
4
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.
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3
3
~
1
4
4
,
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S
N:
2
0
8
9
-
3
3
3
7
.
[3
]
W
e
n
ju
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n
F
a
n
,
S
h
a
n
li
n
Ya
n
g
,
“
M
u
lt
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S
o
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rc
e
In
f
o
rm
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ti
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n
S
e
rv
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S
IS
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r
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ss
M
a
n
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g
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t
in
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d
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u
ti
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v
iro
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m
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t,
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ter
n
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ti
o
n
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l
J
o
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rn
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l
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u
d
C
o
mp
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ti
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g
a
n
d
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e
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S
c
ien
c
e
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I
J
-
CL
OS
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)
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1
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1
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a
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0
1
2
,
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p
.
1
7
~
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4
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S
N:
2
0
8
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3
3
7
[4
]
A
z
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e
m
S
a
r
w
a
r,
M
u
h
a
m
m
a
d
Na
e
e
m
A
h
m
e
d
K
h
a
n
,
“
A
Re
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w
o
f
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ru
st
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sp
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ts
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Clo
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d
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ti
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n
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S
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e
(
IJ
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CL
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)
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.
2
,
N
o
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2
,
A
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0
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3
,
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p
.
1
1
6
~
1
2
2
IS
S
N:
2
0
8
9
-
3
3
3
7
[5
]
Z.
M
a
h
m
o
o
d
,
“
Da
ta
L
o
c
a
t
io
n
a
n
d
S
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u
rity
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u
e
s
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n
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o
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d
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,
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EE
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ta an
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T
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2
0
1
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.
[6
]
A
.
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e
h
l,
“
Eme
rg
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S
e
c
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rit
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Ch
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ll
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in
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ti
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,
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IEE
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T
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ICT
),
2
0
1
1
.
[7
]
D.
Ch
e
n
,
H.
Zh
a
o
,
“
Da
t
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S
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c
u
rity
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n
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Priva
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y
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te
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ti
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n
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e
s
in
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d
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ics
E
n
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2
0
1
2
.
[8
]
K.
P
o
p
o
v
ic,
Z.
Ho
c
e
n
sk
i,
“
Clo
u
d
Co
mp
u
ti
n
g
se
c
u
rity
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e
s
a
n
d
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h
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”
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I
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RO,
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th
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3
3
r
d
In
tern
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l
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,
2
0
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[9
]
S
ian
i
a
n
d
M
iran
d
a
,
“
S
e
c
u
rity
T
h
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ts
in
c
lo
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mp
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,
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6
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ter
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T
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h
n
o
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n
d
S
e
c
u
re
T
ra
n
sa
c
ti
o
n
s,
2
0
1
1
.
[1
0
]
He
n
a
S
h
a
b
e
e
b
,
N.
Je
y
a
n
th
i,
N.Ch
.
S
.
N.
Iy
e
n
g
a
r,
“
A
S
tu
d
y
o
n
S
e
c
u
rit
y
T
h
re
a
ts
in
Clo
u
d
,”
I
n
ter
n
a
t
io
n
a
l
J
o
u
r
n
a
l
o
f
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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t J
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&
C
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p
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I
SS
N:
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-
8708
Mig
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tin
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(
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.
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n
d
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la
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219
Clo
u
d
Co
m
p
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ti
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g
a
n
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s S
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1
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Da
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u
n
,
G
u
iran
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a
n
g
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L
in
a
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e
Dire
c
t,
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p
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2
8
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5
6
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[1
2
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Dim
it
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Zi
ss
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Dim
it
rio
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L
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k
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s,
“
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d
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e
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t
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1
2
,
p
p
.
5
8
3
–
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9
2
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[1
3
]
Jo
h
n
C.
R
o
b
e
rts
II,
W
a
sim
A
l
-
H
a
m
d
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n
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“
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h
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n
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rit
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e
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wit
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i
n
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u
d
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m
p
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g
”
,
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1
1
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5
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9
.
[1
4
]
Jo
h
n
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ra
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z
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o
ri
M
.
Ka
u
fm
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n
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c
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f
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d
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”
,
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2
0
0
9
,
p
p
.
6
1
-
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4
.
[1
5
]
S
.
S
u
b
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sh
in
i
n
,
V.
Ka
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it
h
a
,
“
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s
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c
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rit
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0
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p
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1
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[1
6
]
F
a
h
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d
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.
A
lru
wa
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T
.
A
a
ro
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ll
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,”
In
ter
n
a
ti
o
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l
J
o
u
rn
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o
f
Cl
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d
C
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ti
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n
d
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s
S
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ien
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(
IJ
-
CL
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ER
)
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l.
3
,
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2
,
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p
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2
0
1
4
,
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p
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8
7
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6
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S
N:
2
0
8
9
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3
3
3
7
.
[1
7
]
A
sh
ish
Ku
m
a
r,
“
W
o
rld
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f
Clo
u
d
Co
m
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&
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,
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ter
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