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Feb
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2020
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p
p
.
3
8
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5
I
SS
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2088
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8708
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DOI
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2088
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
10
,
No
.
1
,
Feb
r
u
ar
y
2
0
2
0
:
3
8
7
-
395
388
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e
S
u
p
er
v
is
o
r
y
C
o
n
tr
o
l
an
d
Data
A
cq
u
is
i
tio
n
(
SC
AD
A
)
s
y
s
te
m
[
5
]
is
m
ain
l
y
u
s
ed
a
s
an
I
n
d
u
s
tr
ial
C
o
n
tr
o
l
S
y
s
te
m
(
I
C
S)
in
t
h
e
I
I
o
T
en
v
ir
o
n
m
e
n
t.
T
h
e
m
ain
r
o
le
o
f
th
e
S
C
A
D
A
s
y
s
te
m
is
to
f
ee
d
th
e
r
ea
l
-
ti
m
e
s
y
s
te
m
p
er
f
o
r
m
a
n
ce
d
ata
i
n
to
h
i
g
h
er
le
v
el
I
T
s
u
p
p
o
r
t
s
y
s
te
m
s
f
o
r
d
ec
is
io
n
-
m
a
k
i
n
g
p
r
o
ce
s
s
e
s
.
T
h
e
g
e
n
er
al
ar
ch
itect
u
r
e
o
f
t
h
e
SC
A
D
A
s
y
s
te
m
is
s
h
o
w
n
in
F
ig
u
r
e
1
.
I
t
p
r
o
v
id
es
in
s
ta
n
t
ac
ce
s
s
to
r
ea
l
-
ti
m
e
in
f
o
r
m
atio
n
f
o
r
m
ak
i
n
g
d
ata
-
d
r
iv
en
d
ec
is
io
n
s
in
o
r
d
er
to
im
p
r
o
v
e
ef
f
icie
n
c
y
,
p
er
f
o
r
m
a
n
ce
,
c
u
s
to
m
er
ex
p
er
i
en
ce
an
d
co
n
tr
o
l
in
d
u
s
tr
ial
p
r
o
ce
s
s
es
r
e
m
o
te
l
y
.
Ho
w
e
v
er
,
s
tr
ateg
ic
p
la
n
s
f
o
r
s
ec
u
r
i
n
g
t
h
e
I
o
T
d
ev
ices
h
av
e
n
o
t
b
ee
n
k
ep
t
u
p
w
it
h
t
h
e
r
ap
id
d
ev
elo
p
m
en
t
an
d
in
n
o
v
a
tio
n
s
h
ap
p
en
i
n
g
i
n
I
I
o
T
s
ec
to
r
s
w
h
ic
h
e
n
ab
les
m
an
y
n
e
w
c
h
alle
n
g
e
s
i
n
t
h
e
c
y
b
er
s
ec
u
r
it
y
lan
d
s
ca
p
e
[
6
]
.
T
h
e
in
te
g
r
atio
n
o
f
I
o
T
w
it
h
th
e
ex
i
s
t
i
n
g
S
C
A
D
A
s
y
s
te
m
i
n
th
e
in
d
u
s
tr
y
e
n
v
ir
o
n
m
en
t
ca
n
i
n
tr
o
d
u
ce
m
a
n
y
k
in
d
s
o
f
s
ec
u
r
it
y
r
i
s
k
s
to
th
e
s
y
s
te
m
.
Fig
u
r
e
1
.
T
h
e
ar
ch
itectu
r
e
o
f
t
h
e
SC
AD
A
s
y
s
te
m
i
n
t
h
e
I
n
d
u
s
tr
ial
I
o
T
(
I
I
o
T
)
en
v
ir
o
n
m
e
n
t
T
h
e
I
I
o
T
en
v
ir
o
n
m
e
n
t
n
ee
d
s
lo
w
-
co
s
t
s
m
ar
t
s
e
n
s
o
r
s
t
h
at
s
h
o
u
ld
b
e
r
eliab
le,
ea
s
il
y
d
ep
l
o
y
ab
le
a
n
d
co
n
f
i
g
u
r
ab
le.
I
t
s
h
o
u
ld
e
x
h
i
b
it
ap
p
licatio
n
-
lev
el
i
n
ter
o
p
er
ab
ilit
y
a
n
d
f
au
l
t
to
ler
an
ce
ca
p
ab
ilit
ies
u
n
d
er
co
m
m
u
n
icatio
n
i
m
p
air
m
e
n
ts
.
I
t sh
o
u
ld
also
p
r
o
v
id
e
s
ca
lab
il
it
y
,
s
ec
u
r
it
y
a
n
d
p
r
iv
ac
y
r
eq
u
i
r
e
m
en
t
s
to
it
s
u
s
er
s
.
I
n
o
r
d
er
to
p
r
o
v
id
e
ef
f
ec
tiv
e
s
ec
u
r
it
y
co
n
tr
o
l
m
ec
h
a
n
is
m
in
t
h
e
I
I
o
T
lan
d
s
ca
p
e,
m
an
y
au
th
e
n
ticatio
n
m
ec
h
a
n
i
s
m
s
h
a
v
e
b
ee
n
p
r
o
p
o
s
ed
[
7
,
8
]
.
Ho
w
e
v
er
,
th
e
li
m
ited
co
m
p
u
tatio
n
al
p
o
w
er
o
f
d
ev
ice
s
an
d
lo
w
b
an
d
w
id
t
h
o
f
co
m
m
u
n
icatio
n
ch
a
n
n
els
p
r
ev
e
n
ts
t
h
o
s
e
m
ec
h
a
n
i
s
m
s
d
ir
ec
t
l
y
ap
p
lied
to
th
e
I
I
o
T
s
ec
to
r
.
I
n
th
i
s
p
ap
er
,
a
r
eliab
le
n
ex
t
-
g
en
er
atio
n
c
y
b
er
s
ec
u
r
it
y
a
r
ch
itect
u
r
e
is
p
r
o
p
o
s
ed
to
a
u
th
e
n
tica
te
en
ti
ties
in
v
o
l
v
ed
i
n
w
ir
ele
s
s
co
m
m
u
n
icatio
n
.
I
t
e
n
s
u
r
es
th
e
in
te
g
r
it
y
o
f
t
h
e
r
ea
l
-
ti
m
e
cr
itical
in
f
o
r
m
atio
n
ex
c
h
a
n
g
ed
b
et
w
ee
n
th
o
s
e
e
n
tit
ies i
n
th
e
I
I
o
T
n
et
w
o
r
k
.
a.
Cy
ber
s
ec
urit
y
cha
lleng
es in
t
he
I
I
o
T
l
a
nd
s
ca
pe
T
h
er
e
is
a
m
u
ltit
u
d
e
o
f
c
y
b
er
s
ec
u
r
it
y
t
h
r
ea
ts
e
m
er
g
i
n
g
i
n
t
h
e
in
f
o
r
m
at
io
n
er
a
th
at
a
r
e
m
ai
n
l
y
tar
g
eti
n
g
o
r
g
an
iza
tio
n
s
a
n
d
in
d
u
s
tr
ies
at
lar
g
e.
T
h
e
I
I
o
T
n
et
w
o
r
k
en
v
ir
o
n
m
e
n
t
is
s
h
o
w
n
in
F
ig
u
r
e
2
.
Ma
n
y
c
y
b
er
s
ec
u
r
it
y
c
h
alle
n
g
es
[
9
]
an
d
s
o
lu
tio
n
s
[
1
0
,
1
1
]
h
av
e
b
ee
n
ad
d
r
ess
ed
in
th
is
en
v
ir
o
n
m
e
n
t
to
m
iti
g
ate
s
ec
u
r
it
y
v
u
l
n
er
ab
ilit
ies
an
d
t
h
r
ea
ts
.
W
ith
o
u
t
h
a
v
in
g
a
w
e
ll
-
d
esi
g
n
ed
s
ec
u
r
it
y
i
n
f
r
astr
u
ctu
r
e
f
o
r
an
y
I
I
o
T
d
ep
lo
y
m
en
t
s
,
an
o
r
g
a
n
izatio
n
s
h
o
u
ld
en
co
u
n
ter
a
co
n
s
id
er
ab
le
a
m
o
u
n
t
o
f
d
a
m
a
g
es
to
its
as
s
ets
an
d
r
ep
u
tatio
n
o
v
er
ti
m
e.
T
h
is
s
ec
tio
n
d
is
c
u
s
s
es
d
if
f
er
en
t
k
i
n
d
s
o
f
s
ec
u
r
it
y
attac
k
s
an
d
m
aj
o
r
cy
b
er
s
ec
u
r
it
y
ch
alle
n
g
es
n
ee
d
ed
to
en
v
is
a
g
e
a
s
ec
u
r
it
y
f
r
a
m
e
w
o
r
k
f
o
r
th
e
I
I
o
T
en
v
ir
o
n
m
e
n
t [
1
2
]
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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&
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m
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g
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SS
N:
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ex
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b
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tern
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(
C
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389
Fig
u
r
e
2
.
T
h
e
I
I
o
T
n
et
w
o
r
k
e
n
v
ir
o
n
m
en
t
b.
Dif
f
er
ent
s
ec
urit
y
a
t
t
a
ck
s
in
I
I
o
T
net
w
o
rk
Mo
s
t
o
f
th
e
cr
itical
i
n
f
r
astr
u
c
tu
r
e
is
v
u
l
n
er
ab
le
to
s
ec
u
r
it
y
attac
k
s
.
T
h
e
class
if
icatio
n
o
f
d
if
f
er
e
n
t
s
ec
u
r
it
y
attac
k
s
i
n
th
e
I
I
o
T
n
etw
o
r
k
la
n
d
s
ca
p
e
ar
e
ca
teg
o
r
ized
as f
o
llo
w
s
:
A
ttac
k
s
o
n
P
h
y
s
ical
C
o
m
p
o
n
en
ts
:
Attack
s
o
n
p
h
y
s
ical
co
m
p
o
n
en
ts
o
f
I
I
o
T
r
eq
u
ir
e
u
n
au
th
o
r
ize
d
ac
ce
s
s
to
s
e
n
s
i
n
g
d
ev
ice
s
,
co
n
tr
o
l
s
y
s
te
m
s
an
d
ac
t
u
ato
r
s
[
1
3
]
.
Hac
k
er
s
h
a
v
e
v
ar
io
u
s
o
p
tio
n
s
at
t
h
eir
d
is
p
o
s
al
to
in
te
r
ce
p
t
th
e
r
ad
io
s
ig
n
als
a
n
d
clo
n
e
it
to
ex
tr
ac
t
t
h
e
s
ec
u
r
it
y
cr
ed
en
tial
s
w
h
ich
ca
u
s
e
s
ig
n
i
f
ican
t
d
a
m
a
g
e
to
cr
itical
in
f
r
astr
u
ctu
r
e
i
n
th
e
i
n
d
u
s
tr
ial
co
n
tr
o
l s
y
s
te
m
s
.
A
ttac
k
s
o
n
So
f
t
w
ar
e
C
o
m
p
o
n
en
t
s
:
A
ttac
k
er
s
i
n
j
ec
ts
v
ar
i
o
u
s
k
i
n
d
s
o
f
m
al
w
ar
e
s
u
c
h
as
Vir
u
s
e
s
,
T
r
o
j
an
s
,
an
d
W
o
r
m
s
to
s
ee
h
o
w
t
h
e
y
r
ea
ct
i
n
t
h
e
s
y
s
te
m
.
T
h
e
d
is
tr
ib
u
ted
d
en
ial
o
f
s
er
v
ice
(
DDo
S)
attac
k
s
ca
n
d
is
tu
r
b
t
h
e
r
eg
u
lar
o
p
er
atio
n
o
f
t
h
e
s
y
s
te
m
s
u
n
d
er
co
n
tr
o
l.
Fo
r
an
i
n
s
t
a
n
ce
,
i
n
I
I
o
T
s
ec
to
r
,
attac
k
o
n
th
e
s
a
f
et
y
-
cr
itica
l
in
f
o
r
m
atio
n
s
u
c
h
as
w
a
r
n
in
g
o
f
a
b
r
o
k
en
g
as
p
ip
eli
n
e
ca
n
b
e
d
o
n
e
th
r
o
u
g
h
th
e
DDo
S
attac
k
s
[
1
4
]
to
s
u
p
p
r
ess
th
e
w
ar
n
in
g
m
es
s
ag
e
s
th
at
ca
n
g
o
u
n
n
o
ticed
.
E
ac
h
u
p
d
ate
o
f
th
e
s
o
f
t
w
ar
e
m
u
s
t
b
e
s
ig
n
ed
(
v
er
if
ied
)
b
ef
o
r
e
f
las
h
i
n
g
i
n
to
a
d
ev
ice
to
ac
co
m
p
lis
h
au
th
e
n
tici
t
y
.
A
ttac
k
s
o
n
Net
w
o
r
k
C
o
m
p
o
n
en
ts
:
W
ir
eless
co
n
n
ec
tiv
it
y
b
et
w
ee
n
d
e
v
ices
f
ac
il
itates
r
e
m
o
te
ac
ce
s
s
.
Ho
w
e
v
er
,
it
is
also
th
e
b
ig
g
e
s
t
v
u
ln
er
ab
le
p
o
in
t
i
n
th
e
I
I
o
T
n
et
w
o
r
k
f
r
o
m
w
h
ic
h
th
e
at
tack
er
s
ca
n
ex
p
lo
it
th
e
w
h
o
le
n
e
t
w
o
r
k
co
m
p
o
n
e
n
ts
r
e
m
o
tel
y
.
I
n
tr
u
d
er
s
ca
n
in
it
iate
p
o
s
s
ib
l
e
at
tack
s
o
n
t
h
e
n
o
d
es
co
n
n
ec
ted
to
th
e
w
ir
ele
s
s
n
et
w
o
r
k
.
I
n
f
ac
t
,
a
clo
u
d
i
n
f
r
astru
c
tu
r
e
co
u
ld
b
e
u
s
ed
to
co
n
tr
o
l
t
h
e
n
et
wo
r
k
ed
I
o
T
d
ev
ices
co
n
n
ec
ted
th
r
o
u
g
h
a
g
ate
w
a
y
[
1
5
]
.
T
h
u
s
,
if
t
h
e
g
ate
w
a
y
n
o
d
e
h
as
b
ee
n
co
m
p
r
o
m
is
ed
b
y
an
attac
k
er
,
th
e
w
h
o
le
I
I
o
T
s
y
s
te
m
ca
n
b
e
d
o
w
n
an
d
b
ec
o
m
e
s
cr
itic
al.
E
ac
h
e
n
d
-
to
-
e
n
d
s
es
s
io
n
ca
n
b
e
e
n
cr
y
p
ted
at
th
e
e
n
d
-
p
o
in
ts
to
av
o
id
s
ec
u
r
it
y
t
h
r
ea
ts
i
n
t
h
e
n
et
w
o
r
k
.
T
h
e
lack
o
f
w
el
l
-
e
s
tab
lis
h
ed
b
u
s
i
n
es
s
p
r
o
ce
s
s
e
s
,
m
at
u
r
e
tech
n
o
lo
g
ies,
an
d
p
r
o
lif
er
atio
n
o
f
d
if
f
er
en
t
d
ev
ice
s
tan
d
ar
d
s
cr
ea
te
co
m
p
le
x
itie
s
in
th
e
I
I
o
T
s
ec
to
r
w
h
ic
h
in
t
u
r
n
,
m
a
k
es
it
d
if
f
ic
u
lt
to
tack
le
all
k
i
n
d
s
o
f
s
ec
u
r
it
y
attac
k
s
[
1
6
]
.
T
h
u
s
a
w
e
ll
-
e
s
tab
lis
h
ed
c
y
b
er
s
ec
u
r
it
y
s
o
l
u
tio
n
i
s
ess
e
n
tial to
s
ec
u
r
e
th
e
I
I
o
T
lan
d
s
ca
p
e.
c.
Securit
y
re
qu
ire
m
e
nts f
o
r
I
I
o
T
la
nd
s
ca
pe
An
y
f
r
a
m
e
w
o
r
k
en
v
i
s
ag
ed
f
o
r
I
I
o
T
en
v
ir
o
n
m
e
n
t s
h
o
u
ld
m
ee
t
th
e
f
o
llo
w
i
n
g
s
ec
u
r
i
t
y
r
eq
u
ir
e
m
en
ts
:
1.
Secu
r
it
y
:
I
t
p
r
o
v
id
es
a
s
s
u
r
an
c
e
to
t
h
e
u
s
er
o
f
a
s
y
s
te
m
th
a
t
all
co
m
p
o
n
en
ts
u
s
ed
in
t
h
e
s
y
s
te
m
ar
e
w
ell
p
r
o
tecte
d
an
d
r
em
ai
n
s
ec
u
r
e
f
r
o
m
o
u
t
s
id
e
th
r
ea
ts
a
n
d
attac
k
s
t
h
at
tr
y
to
co
m
p
r
o
m
is
e
t
h
e
s
y
s
te
m
.
I
t
also
ass
u
r
es
t
h
at
t
h
e
co
n
f
id
e
n
tialit
y
a
n
d
in
te
g
r
it
y
o
f
th
e
s
y
s
te
m
w
il
l
r
e
m
a
in
in
tact
an
d
t
h
e
i
n
f
o
r
m
atio
n
w
ill
n
o
t
b
e
d
is
clo
s
ed
at
an
y
co
s
t
to
an
y
u
n
au
t
h
o
r
ized
en
tit
y
.
I
t
ass
u
r
es
th
e
a
v
ailab
ilit
y
o
f
t
h
e
s
y
s
te
m
to
it
s
au
t
h
o
r
ized
u
s
er
an
d
en
ab
les i
n
s
tan
ta
n
eo
u
s
ac
ce
s
s
to
t
h
e
in
f
o
r
m
atio
n
.
2.
P
r
iv
ac
y
: I
t
is
th
e
ab
ilit
y
o
f
t
h
e
s
y
s
te
m
u
n
d
er
co
n
tr
o
l th
at
p
r
o
v
id
es c
o
n
tr
o
lled
ac
ce
s
s
to
i
ts
in
f
o
r
m
atio
n
f
lo
w
w
it
h
i
n
t
h
e
o
r
g
an
iza
tio
n
al
s
e
tu
p
.
3.
R
eliab
ilit
y
:
I
t
is
t
h
e
ab
ilit
y
o
f
a
s
y
s
te
m
t
h
at
s
h
o
u
ld
p
er
f
o
r
m
its
r
eq
u
ir
ed
f
u
n
ctio
n
s
u
n
d
er
s
t
ated
co
n
d
itio
n
s
w
it
h
i
n
t
h
e
s
p
ec
if
ied
p
er
io
d
4.
Saf
et
y
:
I
t
is
th
e
m
o
s
t
i
m
p
o
r
tan
t
r
eq
u
ir
e
m
e
n
t
f
o
r
an
y
I
I
o
T
s
ec
to
r
s
t
h
at
p
r
o
v
id
es
an
a
m
icab
le
w
o
r
k
in
g
co
n
d
itio
n
at
w
h
ic
h
t
h
e
u
s
er
o
f
th
e
s
y
s
te
m
s
h
o
u
ld
n
o
t
p
o
s
e
an
y
p
o
ten
tia
l
t
h
r
ea
t
o
f
d
a
n
g
er
.
I
t
s
h
o
u
ld
s
af
e
g
u
ar
d
b
o
th
p
eo
p
le
an
d
p
h
y
s
ical
ass
e
ts
i
n
th
e
w
o
r
k
in
g
en
v
ir
o
n
m
e
n
t.
5.
R
esil
ie
n
ce
:
I
t
p
r
o
v
id
es
f
au
lt
-
to
ler
an
ce
ca
p
ab
ilit
ies
to
th
e
s
y
s
t
e
m
w
h
e
n
a
f
ail
u
r
e
o
cc
u
r
s
.
T
h
e
s
y
s
te
m
s
h
o
u
l
d
ac
co
m
p
li
s
h
its
f
u
n
ctio
n
s
th
r
o
u
g
h
m
ea
n
i
n
g
f
u
l
alter
n
ati
v
e
w
a
y
s
w
h
e
n
it
en
co
u
n
ter
s
s
o
m
e
f
ai
lu
r
es.
I
f
a
s
in
g
le
co
m
p
o
n
e
n
t
o
f
t
h
e
s
y
s
te
m
h
as
en
co
u
n
ter
ed
a
f
ai
lu
r
e,
it
w
o
u
ld
n
o
t
a
f
f
ec
t
o
th
er
p
ar
ts
.
T
h
e
s
y
s
te
m
s
h
o
u
ld
au
to
m
a
ticall
y
o
v
er
co
m
e
w
it
h
t
h
at
f
a
ilu
r
e
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2088
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
10
,
No
.
1
,
Feb
r
u
ar
y
2
0
2
0
:
3
8
7
-
395
390
T
h
e
n
o
d
es
o
f
th
e
n
et
w
o
r
k
in
th
e
I
I
o
T
lan
d
s
ca
p
e
ar
e
in
ter
f
ac
ed
w
ith
a
clo
u
d
-
b
ased
m
a
n
ag
e
m
e
n
t
s
y
s
te
m
(
i
n
teg
r
at
io
n
o
f
SC
AD
A
w
it
h
w
eb
-
b
ased
clo
u
d
s
y
s
t
e
m
th
r
o
u
g
h
a
g
ate
w
a
y
)
f
o
r
p
er
f
o
r
m
i
n
g
v
ar
io
u
s
an
al
y
tics
a
n
d
d
ec
is
io
n
s
m
a
k
i
n
g
p
r
o
ce
s
s
es.
T
h
e
co
m
m
u
n
icati
o
n
en
t
ities
u
s
e
T
C
P
/I
P
p
r
o
to
c
o
l stack
f
o
r
w
ir
ele
s
s
t
r
an
s
m
is
s
io
n
o
f
d
ata
b
et
w
ee
n
th
e
m
w
h
ich
is
m
u
ch
m
o
r
e
s
u
s
ce
p
tib
le
to
s
ec
u
r
it
y
th
r
ea
ts
th
a
n
its
w
ir
ed
co
u
n
ter
p
ar
t.
T
h
e
s
ec
u
r
it
y
b
r
ea
ch
i
m
p
ac
ts
o
n
d
ata
lo
s
s
a
n
d
it
ca
n
e
x
ten
d
i
n
to
t
h
e
ar
ea
s
o
f
h
u
m
a
n
a
n
d
p
h
y
s
ica
l
r
is
k
s
.
T
h
u
s
,
it
i
s
es
s
en
tial
to
h
av
e
a
s
ec
u
r
it
y
s
o
lu
t
io
n
t
h
at
s
h
o
u
ld
ad
d
r
es
s
th
e
v
ar
io
u
s
is
s
u
e
s
r
elate
d
to
th
e
s
ec
u
r
it
y
a
n
d
p
r
iv
ac
y
o
f
th
e
d
ata
s
h
ar
ed
b
et
w
ee
n
e
n
tit
ies i
n
v
o
l
v
ed
in
t
h
e
I
I
o
T
s
ec
to
r
s
[
1
7
,
1
8
]
.
T
h
e
m
ai
n
o
b
j
ec
tiv
e
o
f
th
is
r
esear
ch
p
ap
er
is
to
p
r
esen
t
a
s
ca
lab
le
a
n
d
r
eliab
le
s
ec
u
r
it
y
s
y
s
te
m
a
r
ch
itect
u
r
e
n
a
m
ed
as
“Ne
x
t
Gen
C
y
b
er
Sec
u
r
it
y
A
r
c
h
itect
u
r
e
(
NC
S
A
)
f
o
r
I
I
o
T
A
p
p
licatio
n
s
”
th
a
t
p
r
o
tects
th
e
r
ea
l
-
ti
m
e
d
ata
tr
a
f
f
ics
g
e
n
er
ated
f
r
o
m
v
ar
io
u
s
I
o
T
d
e
v
ices
a
n
d
to
t
h
e
d
ata
s
to
r
ed
in
t
h
e
clo
u
d
s
er
v
er
s
y
s
te
m
.
I
t
p
r
o
v
id
es
t
h
e
r
eq
u
ir
ed
lev
el
o
f
s
ec
u
r
i
t
y
to
t
h
e
s
y
s
te
m
b
y
e
n
ab
lin
g
a
s
u
ita
b
le
au
th
e
n
ticat
io
n
m
ec
h
a
n
i
s
m
a
n
d
b
y
en
f
o
r
cin
g
n
ec
es
s
ar
y
p
o
lic
y
m
an
a
g
e
m
en
t
in
t
h
e
p
r
o
p
o
s
ed
s
e
cu
r
it
y
f
r
a
m
e
w
o
r
k
.
T
h
e
p
r
o
p
o
s
ed
f
r
am
e
w
o
r
k
tr
ie
s
to
ad
d
r
ess
th
e
f
o
llo
w
in
g
k
e
y
q
u
esti
o
n
s
:
a.
Do
es
th
e
e
x
i
s
ti
n
g
co
n
f
ig
u
r
at
io
n
o
f
clo
u
d
in
f
r
astr
u
ct
u
r
e
o
f
t
h
e
I
I
o
T
ap
p
licatio
n
in
tac
t
?
I
n
g
en
er
al,
r
ed
u
n
d
an
c
y
i
n
d
e
v
ice
d
ep
lo
y
m
en
t
i
s
f
o
llo
w
ed
in
t
h
e
I
I
o
T
s
ec
to
r
.
T
h
e
s
y
s
te
m
h
en
ce
co
ll
ec
ts
r
ed
u
n
d
an
t,
d
y
n
a
m
ic
an
d
h
eter
o
g
e
n
eo
u
s
d
ata
an
d
s
to
r
es
th
e
m
i
n
its
clo
u
d
.
T
h
e
co
llected
r
aw
d
ata
s
h
o
u
ld
b
e
c
lean
ed
an
d
f
o
r
m
atted
f
o
r
p
er
f
o
r
m
i
n
g
v
ar
io
u
s
an
al
y
tical
p
r
o
ce
s
s
e
s
.
T
h
u
s
,
th
e
p
r
o
p
o
s
ed
f
r
am
e
w
o
r
k
e
n
s
u
r
es
th
e
d
ata
i
n
teg
r
it
y
a
n
d
p
r
iv
a
c
y
r
eq
u
ir
e
m
en
t
s
o
f
th
e
o
r
g
a
n
izatio
n
th
r
o
u
g
h
a
s
u
itab
le
au
th
e
n
tica
tio
n
m
ec
h
a
n
i
s
m
.
b.
I
s
it
s
ca
lab
le
f
o
r
n
e
w
d
ev
ice
s
i
n
tr
o
d
u
ce
d
in
th
e
e
x
is
tin
g
n
et
wo
r
k
en
v
ir
o
n
m
e
n
t?
Scalab
ilit
y
i
s
ess
e
n
tial
i
n
th
e
I
I
o
T
en
v
ir
o
n
m
e
n
t,
eit
h
er
n
e
w
d
ev
ices
ar
e
in
tr
o
d
u
ce
d
at
an
y
ti
m
e
to
th
e
ex
i
s
ti
n
g
n
e
t
w
o
r
k
o
r
f
ail
u
r
e
d
ev
ices
ca
n
b
e
r
e
m
o
v
ed
f
o
r
d
iag
n
o
s
in
g
a
f
a
u
lt.
T
h
e
p
r
o
p
o
s
ed
cy
b
er
s
ec
u
r
it
y
f
r
a
m
e
w
o
r
k
s
u
p
p
o
r
ts
s
ca
lab
ilit
y
b
y
m
ea
n
s
o
f
d
ev
ice
id
en
tit
y
ta
g
.
c.
W
h
at
ar
e
t
h
e
s
ec
u
r
it
y
a
n
d
p
r
i
v
ac
y
p
o
licies
e
n
f
o
r
ce
d
w
h
e
n
th
e
clo
u
d
i
n
f
r
as
tr
u
ct
u
r
e
w
a
s
h
ac
k
ed
?
Data
co
n
f
id
e
n
tialit
y
s
h
o
u
ld
b
e
m
ai
n
tai
n
ed
w
it
h
in
th
e
I
I
o
T
n
et
w
o
r
k
.
P
r
i
v
ac
y
-
p
r
eser
v
i
n
g
p
o
licie
s
ar
e
u
s
ed
an
d
e
m
p
lo
y
ed
in
t
h
e
p
r
o
p
o
s
ed
s
ch
e
m
e
to
ad
d
r
ess
th
ese
s
ec
u
r
it
y
i
s
s
u
es i
n
th
e
clo
u
d
in
f
r
astru
c
tu
r
e
o
f
I
I
o
T
.
d.
A
r
e
t
h
e
le
g
ac
y
tech
n
o
lo
g
ie
s
s
u
f
f
icie
n
t?
I
f
n
o
t,
d
o
w
e
n
ee
d
an
y
f
u
r
th
er
e
n
h
a
n
ce
m
en
t
to
m
ee
t
t
h
e
ad
d
itio
n
al
r
eq
u
ir
e
m
e
n
ts
o
f
n
e
w
ap
p
licatio
n
s
?
T
h
e
p
r
o
p
o
s
ed
NC
S
A
d
escr
ib
es
w
el
l
-
d
ef
i
n
ed
k
e
y
ca
p
ab
ilit
ies
o
f
I
I
o
T
s
ec
u
r
ity
p
l
atf
o
r
m
t
h
at
i
n
clu
d
e
s
v
ar
io
u
s
a
s
p
ec
ts
o
f
i
n
teg
r
ati
n
g
c
y
b
er
s
ec
u
r
it
y
s
ch
e
m
e
s
in
th
e
ex
i
s
ti
n
g
in
f
r
astru
c
tu
r
e
w
it
h
o
u
t
a
f
f
ec
ti
n
g
t
h
e
o
p
er
atio
n
al
c
h
ar
ac
ter
is
tic
s
o
f
t
h
e
leg
a
c
y
s
y
s
te
m
s
to
av
o
id
v
ar
io
u
s
k
i
n
d
s
o
f
c
y
b
er
s
e
cu
r
it
y
t
h
r
ea
ts
.
T
h
e
r
est
o
f
th
e
p
ap
er
is
o
r
g
a
n
ized
as
f
o
llo
w
s
.
T
h
e
p
r
o
p
o
s
ed
Nex
tGe
n
C
y
b
er
Secu
r
it
y
A
r
ch
itect
u
r
e
(
NC
S
A
)
i
s
d
escr
ib
ed
in
Secti
o
n
2
.
T
h
e
s
ec
u
r
it
y
a
n
al
y
s
i
s
f
o
r
th
e
p
r
o
p
o
s
ed
NC
S
A
i
s
g
iv
e
n
i
n
Sect
io
n
3
a
n
d
th
e
p
er
f
o
r
m
a
n
ce
an
al
y
s
is
o
f
t
h
e
NC
S
A
i
s
g
i
v
e
n
in
Sec
tio
n
4
.
F
in
all
y
,
Sectio
n
5
co
n
clu
d
es t
h
is
r
esear
c
h
w
o
r
k
.
2.
T
H
E
N
E
XT
G
E
N
CYB
E
R
S
E
CUR
I
T
Y
A
RCH
I
T
E
C
T
U
RE
(
NCSA)
F
O
R
I
I
o
T
E
N
V
I
RO
NM
E
NT
Ma
n
y
e
f
f
o
r
ts
h
av
e
b
ee
n
ta
k
en
b
y
r
e
s
ea
r
ch
er
s
i
n
t
h
e
f
ield
o
f
I
I
o
T
to
p
r
o
v
id
e
p
r
o
tectio
n
m
ec
h
an
i
s
m
s
an
d
c
y
b
er
s
ec
u
r
it
y
f
r
a
m
e
w
o
r
k
s
f
o
r
I
I
o
T
a
p
p
licatio
n
s
.
I
n
th
i
s
s
ec
tio
n
,
th
e
s
y
s
te
m
lev
el
s
ec
u
r
it
y
f
r
a
m
e
w
o
r
k
f
o
r
I
I
o
T
lan
d
s
ca
p
e
is
p
r
esen
ted
.
a.
T
he
s
y
s
t
e
m
a
rc
hite
ct
ure
T
h
e
d
au
n
ti
n
g
ta
s
k
in
w
ir
ele
s
s
n
et
w
o
r
k
co
m
m
u
n
icatio
n
e
n
v
ir
o
n
m
e
n
t
i
s
to
d
etec
t
an
d
th
w
ar
t
s
ec
u
r
it
y
-
r
elate
d
th
r
ea
ts
.
T
h
e
s
ec
u
r
it
y
f
r
a
m
e
w
o
r
k
s
d
esi
g
n
ed
f
o
r
m
iti
g
ati
n
g
s
ec
u
r
it
y
v
u
l
n
er
ab
ilit
ies
in
I
I
o
T
s
ec
to
r
s
is
n
eit
h
er
au
to
m
ated
n
o
r
i
n
te
g
r
ated
.
Fo
r
in
s
ta
n
ce
,
it
i
s
d
i
f
f
i
cu
lt
to
a
u
to
m
a
te
t
h
e
u
p
d
ati
n
g
o
f
s
i
g
n
at
u
r
es
i
n
s
ig
n
at
u
r
e
-
b
ased
s
ec
u
r
it
y
s
o
l
u
t
io
n
s
to
d
etec
t
p
o
l
y
m
o
r
p
h
ic
at
tack
s
.
A
b
etter
s
o
l
u
tio
n
ca
n
b
e
ac
h
iev
ed
t
h
r
o
u
g
h
an
au
to
m
ated
c
y
b
er
d
ef
en
s
e
m
ec
h
a
n
i
s
m
t
h
at
ca
n
p
r
o
v
id
e
n
ec
ess
ar
y
p
r
o
tectio
n
ap
p
r
o
ac
h
es
f
o
r
v
ar
io
u
s
t
h
r
ea
ts
in
a
w
ir
eless
e
n
v
ir
o
n
m
e
n
t.
T
h
e
co
m
p
o
n
e
n
ts
o
f
th
e
p
r
o
p
o
s
ed
Nex
tGe
n
c
y
b
er
s
ec
u
r
it
y
ar
c
h
i
tectu
r
e
(
NC
S
A
)
i
s
s
h
o
w
n
in
F
ig
u
r
e
3.
I
t
h
as
t
w
o
p
er
ce
p
tib
le
f
ea
tu
r
es
th
at
e
n
h
a
n
ce
th
e
e
x
is
tin
g
c
y
b
er
d
ef
en
s
e
m
ec
h
an
i
s
m
a
n
d
n
et
w
o
r
k
s
ec
u
r
it
y
.
A
t
f
ir
s
t,
it
p
r
o
v
id
es
s
ca
lab
ilit
y
t
h
at
t
h
e
s
y
s
te
m
ca
n
s
ca
le
f
r
o
m
a
f
e
w
n
o
d
es
to
a
lar
g
e
v
o
lu
m
e
o
f
d
ata
n
o
d
es
in
t
h
e
I
I
o
T
co
m
m
u
n
ic
atio
n
n
et
w
o
r
k
.
A
n
e
w
clien
t
n
o
d
e
ca
n
b
ec
o
m
e
a
m
e
m
b
e
r
b
y
g
e
n
er
ati
n
g
an
au
th
e
n
tica
tio
n
to
k
e
n
w
h
ich
i
s
cr
y
p
to
g
r
ap
h
icall
y
s
i
g
n
ed
.
T
h
e
id
en
tit
y
o
f
th
e
to
k
e
n
(
clien
t
)
is
v
er
if
ied
b
y
an
ad
m
in
i
s
tr
ato
r
n
o
d
e.
T
h
e
g
ate
wa
y
n
o
d
e
au
th
e
n
ticate
s
ea
c
h
s
es
s
io
n
es
tab
lis
h
ed
b
et
w
ee
n
t
h
e
I
o
T
d
ev
ices a
n
d
t
h
e
clo
u
d
s
er
v
er
.
I
t
allo
w
s
o
n
l
y
a
u
th
e
n
tica
ted
tr
af
f
ic
in
t
h
e
n
e
t
w
o
r
k
t
h
r
o
u
g
h
a
tab
le
lo
o
k
-
u
p
m
ec
h
a
n
i
s
m
w
h
ic
h
r
ed
u
ce
s
co
m
p
u
ta
tio
n
al
o
v
er
h
e
ad
s
o
cc
u
r
r
ed
in
co
m
p
lex
n
et
wo
r
k
co
n
tr
o
l p
ac
k
ets.
A
d
y
n
a
m
i
c
an
d
ad
ap
tiv
e
tr
u
s
t
m
ec
h
a
n
i
s
m
ca
n
b
e
ea
s
il
y
i
n
te
g
r
ated
w
it
h
e
x
i
s
ti
n
g
s
ec
u
r
it
y
s
o
lu
tio
n
s
to
p
r
o
v
id
e
c
y
b
er
d
e
f
en
s
e
s
o
lu
t
io
n
s
t
h
at
s
ca
le
w
ell.
T
h
e
tr
u
s
t
m
ec
h
an
i
s
m
e
n
f
o
r
ce
s
a
w
e
ll
-
e
s
tab
lis
h
ed
b
u
s
i
n
ess
r
u
le
(
P
o
lic
y
Ma
n
ag
e
m
en
t)
to
p
r
o
tect
t
h
e
n
et
w
o
r
k
r
eso
u
r
ce
s
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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(
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391
Fig
u
r
e
3
.
T
h
e
n
ex
tg
e
n
c
y
b
er
s
ec
u
r
it
y
ar
c
h
itect
u
r
e
(
NC
S
A
)
f
o
r
an
I
I
o
T
lan
d
s
ca
p
e
T
h
e
s
ec
o
n
d
m
aj
o
r
ca
p
ab
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o
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p
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to
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ti
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tio
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r
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tio
n
m
ec
h
an
i
s
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f
o
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s
y
s
te
m
s
ec
u
r
it
y
t
h
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ad
d
r
ess
es
d
if
f
er
e
n
t
k
i
n
d
s
o
f
s
ec
u
r
it
y
att
ac
k
s
i
n
d
u
ce
d
w
h
e
n
a
s
es
s
io
n
is
estab
li
s
h
ed
.
An
ac
ce
s
s
co
n
tr
o
l
(
A
C
)
m
ec
h
a
n
i
s
m
p
r
elo
ad
ed
in
t
h
e
ad
m
i
n
is
t
r
ato
r
au
th
e
n
ticate
s
a
n
et
w
o
r
k
p
ac
k
et
at
ea
ch
s
ess
io
n
estab
li
s
h
m
e
n
t
p
r
o
ce
s
s
in
ad
v
an
ce
s
o
th
at
o
n
l
y
leg
i
ti
m
ate
n
o
d
e
w
il
l
b
e
allo
w
ed
to
tr
an
s
f
er
p
ac
k
et
s
w
it
h
o
th
er
en
ti
ties
in
t
h
e
w
ir
eless
en
v
ir
o
n
m
en
t.
T
h
e
att
ac
k
er
s
o
u
ts
id
e
o
f
th
e
n
et
w
o
r
k
ca
n
n
o
t
s
ee
t
h
e
p
r
o
tecte
d
r
eso
u
r
ce
s
s
in
ce
th
e
ac
c
e
s
s
co
n
tr
o
l
m
e
ch
an
i
s
m
r
estrict
s
th
e
u
n
a
u
t
h
en
t
icate
d
r
eq
u
est
s
f
r
o
m
t
h
e
o
u
ts
id
e
w
o
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ld
.
T
h
e
ac
ce
s
s
co
n
tr
o
ller
ac
h
iev
e
s
t
h
is
r
estricte
d
ac
ce
s
s
to
d
ata
tr
af
f
ic
t
h
r
o
u
g
h
a
n
en
cr
y
p
t
ed
s
ec
u
r
it
y
to
k
en
t
h
at
ca
n
b
e
in
s
er
ted
in
ea
c
h
s
es
s
io
n
.
b.
Da
t
a
-
lev
el
s
ec
urit
y
in t
he
N
CSA
E
ac
h
d
ev
ice
i
s
as
s
i
g
n
ed
w
i
th
a
u
n
iq
u
e
id
e
n
tit
y
(
n
i
)
i
n
t
h
e
p
r
e
-
d
ep
lo
y
m
e
n
t
p
h
a
s
e.
A
p
u
b
li
c
k
e
y
(
K
r
)
an
d
a
s
ec
r
et
k
e
y
(
K
a
)
i
s
also
ass
i
g
n
ed
f
o
r
ea
ch
n
o
d
e
in
t
h
e
I
I
o
T
n
et
w
o
r
k
.
A
s
h
ar
ed
s
ess
io
n
k
e
y
(
K
s
)
i
s
g
en
er
ated
d
u
r
i
n
g
a
n
et
w
o
r
k
s
ess
io
n
e
s
tab
lis
h
ed
b
et
w
ee
n
n
eig
h
b
o
r
in
g
n
o
d
es
w
h
ic
h
en
s
u
r
es
th
e
s
ec
u
r
it
y
in
th
e
d
ata
e
x
c
h
an
g
ed
b
et
w
ee
n
t
h
o
s
e
n
ei
g
h
b
o
r
s
.
He
n
ce
,
t
h
e
at
tack
er
ca
n
n
o
t
ea
v
esd
r
o
p
s
ec
u
r
it
y
i
n
f
o
r
m
atio
n
i
n
th
e
d
ata
tr
an
s
m
is
s
io
n
p
r
o
ce
s
s
.
Si
m
ilar
l
y
,
t
h
e
in
tr
u
d
er
s
ca
n
n
o
t
p
er
f
o
r
m
n
o
d
e
f
o
r
g
er
y
att
ac
k
b
y
in
tr
o
d
u
ci
n
g
s
o
m
e
m
alicio
u
s
n
o
d
es
in
t
h
e
n
et
w
o
r
k
.
B
ec
au
s
e
th
e
y
ca
n
n
o
t
g
en
er
ate
a
s
ess
io
n
k
e
y
w
i
th
t
h
e
r
eq
u
ir
ed
lev
el
o
f
id
en
titi
e
s
f
o
r
th
e
m
a
licio
u
s
n
o
d
e.
Fo
r
in
s
ta
n
ce
,
le
t
u
s
co
n
s
id
er
a
n
o
d
e
i
n
t
h
e
I
I
o
T
n
et
w
o
r
k
s
en
d
s
th
e
m
o
n
ito
r
ed
in
f
o
r
m
atio
n
i
n
t
h
e
f
o
r
m
o
f
d
ata
p
ac
k
ets
to
th
e
ce
n
tr
al
r
ep
o
s
it
o
r
y
(
C
lo
u
d
Ser
v
er
s
)
s
y
s
te
m
.
A
m
alicio
u
s
n
o
d
e
i
n
t
h
e
co
m
m
u
n
icatio
n
p
ath
u
n
ab
le
to
d
ec
ip
h
er
th
e
co
n
ten
t
o
f
t
h
e
p
ac
k
et,
s
i
n
ce
it
w
as e
n
cr
y
p
te
d
b
y
t
h
e
n
e
g
o
tiated
s
ess
io
n
k
e
y
alo
n
g
w
i
th
t
h
e
p
u
b
lic
an
d
s
ec
r
et
k
e
y
s
o
f
t
h
at
n
o
d
e.
A
p
u
b
lic
k
e
y
en
cr
y
p
t
io
n
alg
o
r
it
h
m
s
u
ch
a
s
R
S
A
i
s
u
s
ed
to
en
cr
y
p
t
t
h
e
p
ac
k
et
tr
an
s
m
i
tted
b
et
wee
n
a
s
o
u
r
ce
n
o
d
e
an
d
a
d
esti
n
atio
n
n
o
d
e.
On
l
y
t
h
e
i
n
te
n
d
ed
r
ec
ip
ien
t c
a
n
d
ec
ip
h
er
t
h
e
r
ec
ei
v
ed
p
ac
k
et
s
.
A
n
ef
f
icie
n
t
k
e
y
-
m
a
n
a
g
e
m
e
n
t p
r
o
to
co
l [
1
9
-
2
1
]
is
u
s
ed
to
g
e
n
er
ate
a
n
d
m
a
n
a
g
e
th
e
k
e
y
s
in
t
h
e
p
r
o
p
o
s
ed
s
y
s
t
e
m
.
T
h
er
e
ar
e
m
an
y
c
h
alle
n
g
e
s
ex
is
t
i
n
t
h
e
c
y
b
er
s
ec
u
r
it
y
m
a
n
a
g
e
m
en
t
f
o
r
I
I
o
T
[
2
2
]
.
I
n
th
e
c
lo
u
d
s
er
v
er
s
id
e,
th
e
p
r
o
p
o
s
ed
f
r
am
e
w
o
r
k
en
f
o
r
ce
s
t
h
e
s
ec
u
r
e
i
n
f
o
r
m
atio
n
s
to
r
ag
e
p
o
licies
i
n
o
r
d
er
to
p
r
eser
v
e
th
e
i
n
te
g
r
it
y
o
f
s
to
r
ed
d
ata
[
2
3
-
25
]
.
T
h
e
d
ata
ar
e
s
to
r
ed
in
t
h
e
e
n
cr
y
p
ted
f
o
r
m
a
t
a
n
d
ca
n
n
o
t
b
e
d
ec
r
y
p
ted
w
it
h
o
u
t
k
n
o
w
i
n
g
th
e
s
ec
r
et
k
e
y
o
f
th
e
e
n
d
u
s
er
.
A
s
p
er
th
e
p
r
e
-
d
ef
i
n
ed
r
u
le
s
g
iv
en
i
n
t
h
e
p
o
lic
y
,
th
e
r
ec
ei
v
ed
p
ac
k
et
s
ca
n
b
e
d
ec
r
y
p
ted
u
s
in
g
t
h
e
s
a
m
e
al
g
o
r
ith
m
u
s
ed
f
o
r
e
n
cr
y
p
ti
n
g
th
e
p
ac
k
ets.
I
n
ad
d
itio
n
to
th
ese
ca
p
ab
ilit
ie
s
,
NC
S
A
p
r
o
v
id
es
n
ec
es
s
ar
y
A
P
I
s
r
eq
u
ir
ed
to
id
en
tify
n
e
t
w
o
r
k
m
an
ag
e
m
e
n
t
p
r
o
ce
s
s
e
s
,
p
r
iv
ac
y
-
p
r
eser
v
i
n
g
p
o
licies,
a
n
d
v
ar
io
u
s
i
n
ter
f
ac
e
s
n
ee
d
ed
f
o
r
s
m
o
o
t
h
o
p
er
atio
n
o
f
th
e
w
h
o
le
n
et
w
o
r
k
i
n
a
co
n
tr
o
lled
m
an
n
er
.
W
ith
t
h
e
i
n
teg
r
atio
n
o
f
al
l
th
e
m
e
ch
an
i
s
m
s
,
a
r
eliab
le
a
u
t
o
m
at
ed
cy
b
er
s
ec
u
r
it
y
ar
ch
itect
u
r
e
ca
n
b
e
en
v
is
a
g
ed
in
an
I
I
o
T
lan
d
s
ca
p
e.
c.
Securing
t
he
net
w
o
rk
t
ra
f
f
ic
t
hro
ug
h II
o
T
g
a
t
ew
a
y
no
de
T
h
e
m
o
s
t
v
alu
ab
le
e
n
tit
y
i
n
t
h
e
I
I
o
T
n
et
w
o
r
k
i
s
t
h
e
s
m
ar
t
s
en
s
o
r
s
th
a
t
h
a
v
e
d
i
f
f
er
en
t
c
alib
r
atio
n
ca
p
ab
ilit
ies
w
it
h
i
n
th
e
s
p
ec
i
f
i
c
lev
el
o
f
to
ler
an
ce
to
p
r
o
v
id
e
a
r
eq
u
ir
ed
d
ata
f
id
elit
y
.
T
h
e
y
g
en
er
ate
d
if
f
er
e
n
t
k
in
d
s
o
f
i
n
f
o
r
m
atio
n
w
it
h
t
h
e
v
ar
y
i
n
g
d
eg
r
ee
o
f
to
ler
an
c
e,
h
o
w
e
v
er
,
t
h
e
r
ec
eiv
i
n
g
e
n
d
m
a
y
u
s
e
a
d
ata
an
al
y
tics
s
y
s
te
m
th
a
t
ca
n
ap
p
ly
a
p
r
e
-
d
ef
i
n
ed
to
ler
an
ce
l
ev
el
(
t
h
r
es
h
o
ld
)
to
ea
ch
s
e
n
s
o
r
m
ea
s
u
r
e
m
e
n
t
s
i
n
o
r
d
er
to
p
r
o
v
id
e
r
ea
l
-
ti
m
e
r
e
s
p
o
n
s
es
to
th
e
u
s
er
.
W
h
en
s
u
ch
s
e
n
s
o
r
s
ar
e
d
ep
lo
y
ed
i
n
ti
m
e
b
o
u
n
d
ed
I
I
o
T
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2088
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
10
,
No
.
1
,
Feb
r
u
ar
y
2
0
2
0
:
3
8
7
-
395
392
lan
d
s
ca
p
e,
th
e
y
m
u
s
t
b
e
p
h
y
s
i
ca
ll
y
s
ec
u
r
ed
to
p
r
ev
e
n
t
u
n
n
e
ce
s
s
ar
y
r
elo
ca
tio
n
o
r
d
eletio
n
f
r
o
m
th
e
n
et
w
o
r
k
.
E
ac
h
s
en
s
o
r
h
as a
u
n
iq
u
e
id
en
tit
y
t
h
at
ca
n
b
e
en
cr
y
p
ted
an
d
v
er
if
ied
f
o
r
au
th
e
n
tica
tio
n
p
u
r
p
o
s
e.
T
h
e
b
asic
ca
p
ab
ilit
y
o
f
th
e
g
ate
w
a
y
s
y
s
te
m
is
to
b
r
id
g
e
all
d
ev
ice
s
in
th
e
in
ter
n
al
n
et
w
o
r
k
to
th
e
e
x
ter
n
al
w
o
r
ld
(
I
n
ter
n
e
t)
t
h
r
o
u
g
h
a
w
ir
ele
s
s
lo
ca
l
n
et
w
o
r
k
in
ter
f
ac
e.
I
t
m
o
n
ito
r
s
all
th
e
n
et
w
o
r
k
tr
a
f
f
ic
an
d
co
n
tr
o
ls
t
h
e
m
to
id
en
ti
f
y
u
n
ex
p
ec
ted
an
d
u
n
w
a
n
ted
co
n
t
en
t
i
n
n
et
w
o
r
k
co
m
m
u
n
icati
o
n
.
I
t
ca
n
ac
h
ie
v
e
th
e
r
eq
u
ir
ed
lev
el
o
f
d
e
f
en
s
e
u
s
in
g
s
e
v
er
al
m
e
th
o
d
s
s
u
c
h
as:
1)
B
y
e
f
f
ec
ti
v
el
y
is
o
lati
n
g
u
n
a
u
t
h
o
r
ized
ex
ter
n
al
n
et
w
o
r
k
tr
af
f
i
c
f
r
o
m
r
ea
c
h
in
g
t
h
e
I
I
o
T
d
ev
ices,
th
e
g
ate
w
a
y
p
r
ev
en
ts
t
h
e
ex
ter
n
al
t
h
r
ea
ts
t
h
at
ar
e
ai
m
ed
to
m
a
n
ip
u
late
t
h
e
d
ev
ice
b
eh
av
io
r
2)
C
o
m
p
r
o
m
i
s
ed
d
ev
ices
ar
e
p
r
e
v
en
ted
f
r
o
m
b
ei
n
g
u
s
ed
to
attac
k
o
th
er
en
titi
e
s
in
eit
h
er
in
t
er
n
al
o
r
ex
ter
n
al
n
et
w
o
r
k
.
Fo
r
ex
a
m
p
le,
a
DDo
S a
ttack
o
r
tr
an
s
m
i
s
s
io
n
o
f
s
e
n
s
iti
v
e
d
ata
to
o
th
er
in
ter
n
et
-
b
a
s
ed
s
y
s
te
m
s
.
T
h
e
n
ex
t
m
aj
o
r
f
u
n
ct
io
n
o
f
th
e
g
ate
w
a
y
s
y
s
te
m
is
to
id
en
ti
f
y
an
d
a
u
t
h
en
t
icate
ea
c
h
d
ev
ice
i
n
th
e
in
ter
n
al
n
e
t
w
o
r
k
.
On
l
y
a
u
th
o
r
ized
d
ev
ices
w
it
h
en
ac
t
in
teg
r
it
y
ca
n
p
ar
ticip
ate
in
n
et
w
o
r
k
o
p
er
atio
n
s
.
T
h
e
g
ate
w
a
y
s
h
o
u
ld
p
r
o
m
p
tl
y
id
en
ti
f
y
,
au
th
o
r
ize
an
d
a
u
t
h
en
ticate
d
ev
ices
co
n
n
ec
ted
i
n
th
e
n
e
t
w
o
r
k
a
n
d
it
s
h
o
u
ld
also
v
er
i
f
y
th
e
i
n
te
g
r
it
y
o
f
t
h
e
s
o
f
t
w
ar
e
i
n
s
talled
o
r
u
p
d
ated
in
th
e
d
e
v
ices.F
in
al
l
y
,
th
e
ap
p
licatio
n
s
an
d
g
a
te
w
a
y
i
n
ter
f
ac
e
s
m
u
s
t
also
b
e
w
ell
s
ec
u
r
ed
th
r
o
u
g
h
a
v
ir
t
u
al
p
r
i
v
ate
n
et
w
o
r
k
(
VP
N)
w
h
ic
h
p
r
ev
e
n
t
s
m
an
ip
u
latio
n
o
f
s
y
s
te
m
m
es
s
a
g
es,
ea
v
e
s
d
r
o
p
p
in
g
,
n
et
w
o
r
k
er
r
o
r
,
an
d
d
ata
co
r
r
u
p
tio
n
.
3.
SE
CUR
I
T
Y
ANA
L
YS
I
S
T
h
is
s
ec
tio
n
a
n
al
y
ze
s
th
e
s
ec
u
r
it
y
o
f
t
h
e
p
r
o
p
o
s
ed
au
th
en
tica
tio
n
m
ec
h
a
n
is
m
as
f
o
llo
w
s
:
a.
P
ro
po
s
it
io
n
1
.
T
he
ide
ntit
y
o
f
t
he
I
I
o
T
dev
ice
s
i
s
s
ec
ured
by
t
he
pro
po
s
ed
a
uthent
ica
t
io
n
m
ec
ha
nis
m
P
ro
o
f
:
T
h
e
id
en
tit
y
o
f
t
h
e
d
e
v
ices
u
s
ed
in
t
h
e
I
I
o
T
n
et
w
o
r
k
is
p
r
o
tecte
d
b
y
g
e
n
er
ati
n
g
a
u
n
iq
u
e
au
th
e
n
tica
tio
n
to
k
en
w
h
ic
h
is
cr
y
p
to
g
r
ap
h
icall
y
en
cr
y
p
ted
u
s
in
g
a
s
tr
o
n
g
p
u
b
lic
k
e
y
cr
y
p
t
o
g
r
ap
h
ic
alg
o
r
it
h
m
s
u
c
h
a
s
SH
A
.
T
h
er
ef
o
r
e,
th
e
attac
k
er
ca
n
n
o
t
o
b
tain
th
e
id
en
tit
y
o
f
t
h
e
d
e
v
ices
w
it
h
o
u
t
co
m
p
r
o
m
i
s
in
g
th
e
s
ec
u
r
it
y
k
e
y
s
g
en
er
ated
d
u
r
in
g
t
h
e
en
cr
y
p
tio
n
a
n
d
d
ec
r
y
p
tio
n
p
r
o
ce
s
s
es.
b.
P
ro
po
rt
io
n 2
.
I
t
preserv
es t
h
e
co
nfident
ia
lity
o
f
t
he
info
r
m
a
t
io
n e
x
cha
ng
ed
in t
he
I
I
o
T
la
nd
s
ca
pe
P
ro
o
f
:
T
h
e
co
n
f
id
en
tiali
t
y
o
f
th
e
i
n
f
o
r
m
at
io
n
i
s
s
ec
u
r
ed
b
y
u
s
i
n
g
a
h
a
s
h
v
al
u
e
o
f
a
r
a
n
d
o
m
n
u
m
b
er
g
en
er
ated
w
h
en
s
s
es
s
io
n
h
as
b
ee
n
estab
lis
h
ed
in
t
h
e
co
m
m
u
n
ica
tio
n
p
r
o
ce
s
s
.
T
h
er
ef
o
r
e,
th
e
ad
v
er
s
ar
y
ca
n
n
o
t
in
ter
ce
p
t a
co
m
m
u
n
icatio
n
s
es
s
io
n
w
it
h
o
u
t
k
n
o
w
in
g
t
h
e
r
an
d
o
m
l
y
g
en
er
ated
h
as
h
v
al
u
e
o
f
th
e
i
d
en
ti
t
y
to
k
en
.
c.
P
ro
po
rt
io
n
3
.
M
utua
l
a
uthent
ica
t
io
n
bet
w
ee
n
dev
ices
a
n
d
g
a
t
ew
a
y
inv
o
lv
ed
in
t
he
co
mm
u
n
ica
t
io
n
is
a
chiev
ed
t
hro
ug
h t
he
pro
p
o
s
ed
a
uthent
ica
t
io
n
m
ec
ha
ni
s
m
P
ro
o
f
:
W
h
ile
r
ec
eiv
in
g
a
j
o
in
r
eq
u
est
m
es
s
a
g
e
f
r
o
m
a
n
e
w
d
ev
ice
o
r
m
e
s
s
a
g
es
to
b
e
s
en
t
to
d
ev
ices,
th
e
g
ate
w
a
y
n
o
d
e
ch
ec
k
s
th
e
id
en
tit
y
to
k
e
n
,
h
a
s
h
v
a
lu
e
a
n
d
th
e
r
an
d
o
m
n
u
m
b
er
g
e
n
er
ated
f
o
r
th
e
d
ev
ice.
T
h
e
m
es
s
ag
e
is
co
n
s
id
er
ed
to
b
e
g
e
n
u
in
e
o
n
l
y
w
h
e
n
eq
u
ali
t
y
h
o
ld
s
g
o
o
d
.
T
h
e
s
a
m
e
v
er
i
f
icatio
n
p
r
o
ce
s
s
i
s
ca
r
r
ied
o
u
t
in
th
e
d
ev
ice
s
id
e
t
o
au
th
e
n
ticate
t
h
e
g
ate
w
a
y
n
o
d
e
w
h
e
n
it
r
ec
eiv
ed
a
m
e
s
s
a
g
e
f
r
o
m
th
e
g
ate
w
a
y
n
o
d
e.
Hen
ce
,
t
h
e
ai
m
o
f
a
n
a
ttack
er
to
f
ak
e
a
d
ev
ice
o
r
th
e
g
ate
w
a
y
n
o
d
e
is
p
r
ev
e
n
ted
s
in
ce
h
e
n
ee
d
s
to
g
en
er
ate
t
h
e
v
al
id
co
m
b
i
n
ati
o
n
o
f
th
e
a
u
th
e
n
ticat
io
n
to
k
e
n
w
h
ic
h
is
v
er
y
d
i
f
f
icu
l
t
to
ac
h
iev
e.
Mo
r
eo
v
er
,
h
e
ca
n
n
o
t a
s
s
u
m
e
th
e
r
a
n
d
o
m
n
u
m
b
er
g
e
n
er
ated
in
t
h
e
m
u
t
u
al
au
th
e
n
tica
tio
n
p
r
o
ce
s
s
.
d.
P
ro
po
rt
io
n
4
.
I
m
per
s
o
na
t
io
n
a
t
t
a
ck
is
prev
ent
ed
i
n
t
he
net
w
o
rk
by
t
he
pro
po
s
ed
a
uthent
ica
t
io
n
m
ec
ha
nis
m
P
ro
o
f
:
T
h
e
p
r
o
p
o
s
ed
au
th
en
t
icatio
n
m
ec
h
a
n
i
s
m
g
u
ar
an
te
es
th
e
u
s
er
th
a
t
a
p
ac
k
et
t
r
an
s
m
itted
b
et
w
ee
n
n
o
d
es
ca
n
n
o
t
b
e
m
o
d
if
ied
b
y
th
e
at
tack
er
w
it
h
o
u
t
k
n
o
w
i
n
g
th
e
h
as
h
v
al
u
es
u
s
ed
in
t
h
e
m
u
t
u
al
au
th
e
n
tica
tio
n
p
r
o
ce
s
s
i
n
v
o
l
v
ed
in
t
h
e
e
s
tab
lis
h
m
e
n
t
o
f
a
s
ec
u
r
e
co
m
m
u
n
ica
tio
n
s
es
s
i
o
n
.
T
h
e
ta
m
p
er
ed
m
es
s
ag
e
s
en
d
b
y
th
e
a
ttack
er
ca
n
ea
s
il
y
b
e
d
etec
ted
b
y
ch
ec
k
i
n
g
th
e
h
as
h
v
a
l
u
es
at
th
e
n
o
d
e
its
el
f
.
Hen
ce
,
th
e
i
m
p
er
s
o
n
at
io
n
atta
ck
ca
n
b
e
p
r
ev
en
ted
i
n
th
e
n
et
w
o
r
k
.
4.
P
E
RF
O
RM
ANCE AN
AL
Y
S
I
S
T
h
e
p
er
f
o
r
m
a
n
ce
o
f
t
h
e
p
r
o
p
o
s
ed
NC
S
A
i
s
an
a
l
y
ze
d
i
n
t
h
i
s
s
ec
tio
n
.
T
h
e
p
er
f
o
r
m
a
n
ce
o
f
NC
S
A
is
ev
alu
a
ted
th
r
o
u
g
h
a
s
i
m
u
latio
n
ex
p
er
i
m
en
tal
s
et
u
p
as
g
i
v
en
in
T
ab
le
1
.
A
p
r
o
to
ty
p
e
o
f
th
e
NC
S
A
is
cr
ea
ted
an
d
d
ep
lo
y
ed
to
m
o
n
ito
r
ce
r
tain
p
ar
a
m
eter
s
(
li
k
e
te
m
p
er
atu
r
e
an
d
p
r
ess
u
r
e)
in
t
h
e
I
I
o
T
lan
d
s
ca
p
e.
T
h
e
p
er
f
o
r
m
an
ce
o
f
th
e
p
r
o
to
ty
p
e
is
test
ed
in
ter
m
s
o
f
th
e
a
m
o
u
n
t
o
f
d
ata
s
ec
u
r
el
y
tr
an
s
m
itted
,
ti
m
e
-
s
y
n
ch
r
o
n
izatio
n
,
d
ata
r
etr
iev
al
ca
p
ab
ilit
y
a
n
d
v
o
lu
m
e
o
f
s
to
r
ag
e
r
eq
u
ir
ed
in
t
h
e
s
er
v
er
s
id
e.
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f
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f
r
o
m
th
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9
d
ev
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an
d
p
er
f
o
r
m
s
an
esti
m
atio
n
o
f
lo
ca
l
te
m
p
er
at
u
r
e
an
d
p
r
ess
u
r
e
at
th
e
d
ep
lo
y
ed
lo
ca
tio
n
in
th
e
I
I
o
T
en
v
ir
o
n
m
en
t
.
T
h
e
esti
m
ated
in
f
o
r
m
atio
n
is
s
e
n
t
to
t
h
e
cl
o
u
d
s
er
v
er
e
v
er
y
1
0
m
i
n
f
o
r
f
u
r
th
er
p
r
o
ce
s
s
i
n
g
.
A
s
p
r
esen
ted
i
n
Fi
g
u
r
e
4
,
th
e
p
r
o
p
o
s
ed
NC
S
A
co
n
s
id
er
ab
ly
r
ed
u
ce
s
b
o
th
th
e
d
ata
tr
a
n
s
m
i
s
s
io
n
o
v
er
h
ea
d
s
a
n
d
s
to
r
ag
e
s
p
ac
e
o
cc
u
p
ied
b
y
t
h
e
d
ata
in
t
h
e
clo
u
d
s
to
r
ag
e
s
y
s
te
m
e
x
ter
n
a
l to
th
e
I
I
o
T
n
et
w
o
r
k
.
T
h
er
ef
o
r
e,
th
e
clo
u
d
s
er
v
er
h
as
to
o
cc
u
p
y
m
o
r
e
s
to
r
a
g
e
s
p
ac
e
to
s
to
r
e
d
ata
in
th
e
clo
u
d
s
to
r
ag
e
s
y
s
te
m
w
it
h
o
u
t
t
h
e
N
C
S
A
f
r
a
m
e
w
o
r
k
.
T
h
e
d
ata
tr
an
s
m
i
s
s
io
n
o
v
er
h
ea
d
o
cc
u
r
s
w
it
h
i
n
t
h
e
i
n
ter
n
al
n
e
t
w
o
r
k
s
i
n
th
e
I
I
o
T
en
v
ir
o
n
m
en
t
d
u
e
to
t
h
e
h
ea
d
er
p
o
r
tio
n
o
f
d
ata
p
ac
k
ets.
T
h
er
e
is
al
w
a
y
s
a
tr
ad
e
-
o
f
f
b
et
w
ee
n
t
h
e
d
ata
tr
an
s
m
is
s
io
n
ti
m
e
a
n
d
t
h
e
d
at
a
p
r
o
ce
s
s
in
g
ti
m
e
in
an
y
w
ir
el
ess
n
et
w
o
r
k
en
v
ir
o
n
m
e
n
t.
T
im
e
e
f
f
icie
n
c
y
ca
n
b
e
ac
h
iev
ed
th
r
o
u
g
h
s
u
itab
le
ti
m
e
s
y
n
c
h
r
o
n
izatio
n
m
ec
h
a
n
i
s
m
.
I
n
t
h
e
ca
s
e
o
f
NC
S
A
,
ti
m
e
-
s
t
a
m
p
m
ec
h
a
n
i
s
m
is
u
s
ed
to
ac
h
ie
v
e
th
e
s
y
n
c
h
r
o
n
iz
atio
n
b
et
w
ee
n
v
ar
io
u
s
n
et
w
o
r
k
ele
m
e
n
t
s
d
u
r
in
g
t
h
e
d
ata
tr
an
s
m
i
s
s
io
n
p
r
o
ce
s
s
.
T
o
s
ec
u
r
e
I
I
o
T
en
v
ir
o
n
m
en
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I
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Vo
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10
,
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1
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Feb
r
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2
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395
394
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c
h
p
ap
er
.
RE
F
E
R
E
NC
E
S
[1
]
L
.
A
t
z
o
ri,
e
t
a
l
.
,
“
T
h
e
In
tern
e
t
o
f
T
h
in
g
s: A
su
rv
e
y
,
”
Co
mp
u
ter
Ne
two
rk
s
,
v
o
l.
5
4
,
p
p
.
2
7
8
7
-
2
8
0
5
,
2
0
1
0
.
[2
]
S
.
M
u
m
taz
,
e
t
a
l
.
,
“
M
a
ss
iv
e
in
te
rn
e
t
o
f
th
i
n
g
s
f
o
r
in
d
u
strial
a
p
p
l
ica
ti
o
n
s:
A
d
d
re
ss
in
g
w
irele
ss
IIo
T
c
o
n
n
e
c
ti
v
it
y
c
h
a
ll
e
n
g
e
s an
d
e
c
o
sy
ste
m
f
ra
g
m
e
n
tatio
n
,
”
IEE
E
In
d
u
stri
a
l
E
lec
tro
n
ics
M
a
g
a
zi
n
e
,
v
o
l
.
1
1
,
p
p
.
2
8
-
3
3
,
2
0
1
7
.
[3
]
L
.
D.
X
u
,
e
t
a
l
.
,
“
In
tern
e
t
o
f
th
in
g
s
in
in
d
u
stries
:
A
su
rv
e
y
,
”
IEE
E
T
ra
n
sa
c
ti
o
n
s
o
n
In
d
u
stri
a
l
In
f
o
r
ma
ti
c
s
,
v
o
l.
1
0
,
p
p
.
2
2
3
3
-
2
2
4
3
,
2
0
1
4
.
[
4
]
V
.
G
a
n
d
h
i,
“
S
e
c
u
ri
ty
Esse
n
ti
a
ls
f
o
r
Io
T
De
p
lo
y
m
e
n
ts
a
n
d
in
C
o
n
n
e
c
ted
S
p
a
c
e
s,”
W
h
it
e
P
a
p
e
r
fro
m
F
r
o
s
t
a
n
d
S
u
l
l
i
v
a
n
,
2
0
1
7
.
[5
]
K.
S
to
u
f
f
e
r,
e
t
a
l
.
,
“
G
u
id
e
to
I
n
d
u
strial
Co
n
tr
o
l
S
y
ste
m
(ICS
)
S
e
c
u
r
it
y
,
”
NIS
T
S
p
e
c
ia
l
Pu
b
li
c
a
t
io
n
,
R
e
v
isio
n
2
,
U.S
.
De
p
a
rtme
n
t
o
f
Co
m
m
e
rc
e
,
2
0
1
5
.
[6
]
A
.
Ko
tt
,
e
t
a
l
.
,
“
S
ix
P
o
ten
t
ial
Ga
m
e
-
Ch
a
n
g
e
rs
in
C
y
b
e
r
S
e
c
u
rit
y
,
”
NAT
O
S
y
mp
o
siu
m
o
n
Cy
b
e
r
S
e
c
u
rity
S
c
ien
c
e
a
n
d
En
g
i
n
e
e
rin
g
,
v
o
l.
4
7
,
p
p
.
1
0
4
-
1
0
6
,
2
0
1
4
.
[7
]
X
.
Ya
o
,
e
t
a
l
.
,
“
A
li
g
h
tw
e
i
g
h
t
m
u
lt
i
-
c
a
st
a
u
th
e
n
ti
c
a
ti
o
n
m
e
c
h
a
n
is
m
f
o
r
s
m
a
ll
sc
a
le
Io
T
a
p
p
li
c
a
ti
o
n
s,
”
IEE
E
S
e
n
so
rs
J
o
u
rn
a
l
,
v
o
l
.
1
3
,
p
p
.
3
6
9
3
-
3
7
0
1
,
2
0
1
3
.
[8
]
W
.
L
.
Ch
in
,
e
t
a
l
.
,
“
A
f
ra
m
e
w
o
rk
o
f
M
a
c
h
in
e
-
to
-
M
a
c
h
in
e
a
u
t
h
e
n
ti
c
a
ti
o
n
i
n
sm
a
rt
g
rid
:
A
tw
o
-
la
y
e
r
a
p
p
ro
a
c
h
,
”
IEE
E
Co
mm
u
n
ica
t
io
n
s M
a
g
a
zin
e
,
v
o
l.
5
4
,
p
p
.
1
0
2
-
1
0
7
,
2
0
1
6
.
[9
]
K
.
A
le
x
a
n
d
e
r,
“
T
o
w
a
rd
s
f
u
n
d
a
m
e
n
tal
sc
ien
c
e
o
f
c
y
b
e
r
se
c
u
rit
y
,
”
S
p
rin
g
e
r
J
o
u
rn
a
l
o
n
Ne
two
r
k
S
c
ien
c
e
a
n
d
Cy
b
e
rs
e
c
u
rity
,
p
p
.
1
-
1
3
,
2
0
1
3
.
[1
0
]
A
.
P
a
tch
a
a
n
d
J
.
M
.
P
a
rk
,
“
A
n
o
v
e
rv
ie
w
o
f
a
n
o
m
a
l
y
d
e
te
c
ti
o
n
tec
h
n
i
q
u
e
s:
Ex
isti
n
g
so
lu
ti
o
n
s
a
n
d
late
st
tec
h
n
o
l
o
g
ica
l
tren
d
s,”
IE
EE
tra
n
s
a
c
ti
o
n
o
n
Co
m
p
u
ter
Ne
tw
o
rk
s
,
v
o
l.
5
1
,
p
p
.
3
4
4
8
-
3
4
7
0
,
2
0
0
7
.
[1
1
]
Hitac
h
i
L
td
.
,
“
A
n
a
n
o
m
a
l
y
d
e
tec
ti
o
n
sy
ste
m
f
o
r
a
d
v
a
n
c
e
d
m
a
in
ten
a
n
c
e
,
”
Hita
c
h
i
Rev
iew
,
v
o
l.
6
3
,
2
0
1
4
.
[1
2
]
W
o
rld
Eco
n
o
m
ic
F
o
ru
m
,
“
In
d
u
st
rial
In
tern
e
t
o
f
T
h
in
g
s
S
a
fe
t
y
a
n
d
S
e
c
u
rit
y
Dig
it
a
l
P
ro
to
c
o
l
Ne
tw
o
rk
,
”
Ce
n
ter
fo
r
th
e
Fo
u
rth
In
d
u
stria
l
Rev
o
l
u
ti
o
n
,
2
0
1
6
.
[1
3
]
D.
W
e
lch
a
n
d
S
.
L
a
th
ro
p
,
“
W
irele
ss
se
c
u
rit
y
th
re
a
t
tax
o
n
o
m
y
,
”
In
fo
rm
a
ti
o
n
Ass
u
ra
n
c
e
W
o
rk
sh
o
p
,
IEE
E
S
y
ste
ms
,
M
a
n
a
n
d
Cy
b
e
rn
e
ti
c
s S
o
c
iety
,
p
p
.
7
6
-
8
3
,
2
0
0
3
.
[1
4
]
C.
Ko
li
a
s,
e
t
a
l
.
,
“
DD
o
S
i
n
Io
T
:
M
irai
a
n
d
Oth
e
r
B
o
tn
e
ts,
”
IEE
E
J
o
u
rn
a
l
o
n
C
o
mp
u
ter
,
v
o
l.
5
0
,
p
p
.
8
0
-
8
4
,
2
0
1
7
.
[1
5
]
M
.
He
n
z
e
,
e
t
a
l
.
,
“
A
c
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m
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re
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siv
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h
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th
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l
o
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d
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b
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se
d
In
tern
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t
o
f
T
h
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g
s,
”
Fu
t
u
re
Ge
n
e
ra
ti
o
n
Co
mp
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ter
S
y
ste
ms
,
v
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l.
5
6
,
p
p
.
7
0
1
-
7
1
8
,
2
0
1
6
.
[1
6
]
H.
Ka
w
a
i
,
e
t
a
l
.
,
“
A
c
c
e
ss
A
u
th
e
n
ti
c
a
ti
o
n
–
P
r
o
v
id
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g
F
lex
ib
le
a
n
d
S
e
c
u
re
Ne
t
w
o
rk
Ac
c
e
ss
,
”
NEC
T
e
c
h
n
ica
l
J
o
u
rn
a
l
,
v
o
l
.
8
,
2
0
1
4
.
[1
7
]
K.
A
lex
o
p
o
u
lo
s,
e
t
a
l
.
,
“
A
r
c
h
it
e
c
tu
re
a
n
d
d
e
v
e
lo
p
m
e
n
t
o
f
a
n
In
d
u
strial
In
tern
e
t
o
f
T
h
in
g
s
f
ra
m
e
w
o
rk
f
o
r
re
a
li
z
in
g
se
rv
ice
s in
In
d
u
strial
P
ro
d
u
c
t
S
e
rv
ice
S
y
ste
m
s,”
CIRP
Co
n
fer
e
n
c
e
o
n
M
a
n
u
f
a
c
tu
ri
n
g
S
y
ste
ms
,
p
p
.
8
8
0
-
8
8
5
,
2
0
1
8
.
[1
8
]
R
.
Ch
e
tan
a
n
d
R
.
S
h
a
h
a
b
a
d
k
a
,
“
A
Co
m
p
re
h
e
n
siv
e
S
u
rv
e
y
o
n
Ex
it
in
g
S
o
lu
t
io
n
A
p
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ro
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c
h
e
s
to
w
a
rd
s
S
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c
u
rit
y
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n
d
P
riv
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c
y
R
e
q
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ts
o
f
Io
T
,
”
In
ter
n
a
t
io
n
a
l
J
o
u
rn
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l
o
f
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e
c
tri
c
a
l
a
n
d
Co
mp
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ter
En
g
in
e
e
rin
g
(
IJ
ECE
)
,
v
o
l.
8
,
p
p
.
2
3
1
9
-
2
3
2
6
,
2
0
1
8
.
[1
9
]
Y
.
Be
n
S
li
m
a
n
e
a
n
d
K
.
Be
n
A
h
m
e
d
,
“
Eff
icie
n
t
En
d
-
to
-
E
n
d
S
e
c
u
re
Ke
y
M
a
n
a
g
e
m
e
n
t
P
ro
to
c
o
l
f
o
r
In
tern
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t
o
f
T
h
in
g
s
,
”
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
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e
c
trica
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n
d
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mp
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ter
En
g
in
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rin
g
(
IJ
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)
,
v
o
l.
7
,
p
p
.
3
6
2
2
-
3
6
1
,
2
0
1
7
.
[2
0
]
J
.
M
e
tan
a
n
d
K.N.
N
.
M
u
rt
h
y
,
“
F
S
DA
:
F
ra
m
e
w
o
rk
f
o
r
S
e
c
u
re
D
a
ta
A
g
g
re
g
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ti
o
n
in
W
irele
ss
S
e
n
so
r
Ne
tw
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rk
f
o
r
En
h
a
n
c
i
n
g
Ke
y
M
a
n
a
g
e
m
e
n
t
,
”
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
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e
c
trica
l
a
n
d
C
o
mp
u
ter
En
g
in
e
e
rin
g
(
IJ
ECE
)
,
v
o
l.
8,
p
p
.
4
6
8
4
-
4
6
9
2
,
2
0
1
8
.
[2
1
]
S
.
V.
M
a
n
ik
a
n
t
h
a
n
a
n
d
T
.
P
a
d
m
a
p
riy
a
,
“
A
S
e
c
u
re
d
M
u
lt
i
-
L
e
v
e
l
Ke
y
M
a
n
a
g
e
m
e
n
t
T
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c
h
n
iq
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e
f
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r
In
ten
sif
ied
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irele
ss
S
e
n
so
r
Ne
t
w
o
rk
,
”
In
ter
n
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ti
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n
a
l
J
o
u
r
n
a
l
o
f
Rec
e
n
t
T
e
c
h
n
o
lo
g
y
a
n
d
E
n
g
i
n
e
e
rin
g
,
v
o
l.
7
,
2
0
1
9
.
[2
2
]
M
a
x
i
m
il
ian
L
*
,
M
a
rk
l
E
a
n
d
M
o
h
a
m
e
d
A
.
“
C
y
b
e
rs
e
c
u
rit
y
M
a
n
a
g
e
m
e
n
t
f
o
r
(In
d
u
strial)
In
ter
n
e
t
o
f
T
h
in
g
s:
Ch
a
ll
e
n
g
e
s an
d
Op
p
o
rt
u
n
it
ies
,
”
J
o
u
rn
a
l
o
f
I
n
fo
rm
a
ti
o
n
T
e
c
h
n
o
l
o
g
y
&
S
o
ft
wa
re
En
g
i
n
e
e
rin
g
,
v
o
l.
8
,
2
0
1
8
.
[2
3
]
S
a
h
m
i
m
S
,
a
n
d
G
h
a
rse
ll
a
o
u
i
H,”
P
riv
a
c
y
a
n
d
S
e
c
u
rit
y
in
In
tern
e
t
-
b
a
se
d
Co
m
p
u
ti
n
g
:
C
lo
u
d
C
o
m
p
u
ti
n
g
,
In
tern
e
t
o
f
T
h
in
g
s,
Clo
u
d
o
f
T
h
in
g
s: a rev
ie
w
,
”
Pro
c
e
d
ia
Co
mp
u
ter
S
c
ien
c
e
,
V
o
l
.
1
1
2
,
p
p
.
1
5
1
6
-
1
5
2
2
,
2
0
1
7
.
[2
4
]
Hu
g
h
Bo
y
e
s,
Bil
Ha
ll
a
q
,
Jo
e
Cu
n
n
in
g
h
a
m
a
n
d
T
i
m
Watso
n
,
”
T
h
e
in
d
u
strial
in
tern
e
t
o
f
th
in
g
s
(IIo
T
):
A
n
a
n
a
l
y
sis
f
ra
m
e
w
o
rk
,
”
Co
mp
u
ter
s in
I
n
d
u
st
ry
,
V
o
l.
1
0
1
,
p
p
.
1
-
1
2
,
2
0
1
8
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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N:
2088
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8708
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(
C
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395
[2
5
]
S.
Je
sc
h
k
e
,
C.
Bre
c
h
e
r,
T.
M
e
ise
n
,
D.
Öz
d
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m
ir,
a
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d
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Esc
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rt,
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d
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ter
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o
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l
In
ter
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g
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p
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3
-
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.
B
I
O
G
RAP
H
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O
F
AUTH
O
RS
Ch
e
ll
a
v
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ij
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stit
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p
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h
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h
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d
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re
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&
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f
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h
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Un
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y
)
a
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ECT
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o
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o
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(M
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s),
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In
telli
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Da
ta
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Big
Da
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e
h
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se
rv
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v
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tails
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d
a
t
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p
:
//
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w
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sr
m
u
n
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a
c
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in
/en
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g
/co
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f
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lt
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th
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sub
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E
d
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m
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Un
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in
1
9
9
6
M
a
ste
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De
g
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t
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2
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Ch
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n
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a
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2
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1
6
.
He
w
a
s
w
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in
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a
s
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R
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r
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h
S
c
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e
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st
in
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o
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n
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In
f
o
rm
a
ti
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n
tec
h
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lo
g
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Da
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,
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o
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k
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a
.
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o
w
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h
e
is
w
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in
g
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s
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ss
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c
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P
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t
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ll
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m
a
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En
g
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g
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ll
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,
Ch
e
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His
in
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sts
a
re
in
m
o
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c
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p
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tru
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lu
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ti
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n
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c
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d
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o
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p
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ti
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g
.
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is
a
ff
il
iate
d
w
it
h
sc
ien
ti
f
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p
u
b
li
c
a
ti
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n
s,
h
e
h
a
s
se
rv
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s
in
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v
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F
u
rth
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r
in
f
o
o
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h
o
m
e
p
a
g
e
:
h
tt
p
:
//
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w
.
sr
m
v
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l
li
a
m
m
a
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a
c
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in
M
a
n
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g
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t
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lo
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p
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ter
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c
h
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lo
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in
2
0
0
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f
ro
m
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a
tt
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tec
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a
c
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En
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m
A
p
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in
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,
a
ff
li
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ted
to
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n
n
a
Un
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,
a
n
d
M
a
ste
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T
e
c
h
n
o
l
o
g
y
f
ro
m
S
RM
Un
iv
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Cu
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