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ac
ts
[
1
2
,
1
3
]
.
T
h
e
alg
o
r
ith
m
s
ar
e
d
ev
elo
p
ed
ar
o
u
n
d
th
e
co
m
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u
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r
d
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ess
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u
m
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ic
h
ar
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h
ar
d
to
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r
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k
b
y
an
ad
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er
s
ar
y
.
T
h
e
F
ig
u
r
e
1
illu
s
tr
ates th
e
e
n
cr
y
p
tio
n
al
g
o
r
ith
m
.
Fig
u
r
e
1
.
E
n
cr
y
p
tio
n
al
g
o
r
ith
m
T
h
er
e
ar
e
tw
o
m
aj
o
r
r
eq
u
ir
e
m
en
ts
f
o
r
th
e
cr
y
p
to
g
r
ap
h
y
[
1
4
-
1
6
]:
a.
T
h
e
f
ir
s
t
is
t
h
at
it
m
u
s
t
b
e
co
m
p
u
tatio
n
all
y
in
f
ea
s
ib
le
to
w
ar
d
s
d
er
iv
i
n
g
th
e
p
lai
n
te
x
t
f
r
o
m
cip
h
er
te
x
t
w
it
h
i
n
t
h
e
k
n
o
w
led
g
e
o
f
d
ec
r
y
p
tio
n
k
e
y
b.
An
o
th
er
r
eq
u
ir
e
m
e
n
t
is
th
a
t
i
t
m
u
s
t
b
e
co
m
p
u
tatio
n
all
y
i
n
f
ea
s
ib
le
to
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er
iv
e
c
y
p
h
er
te
x
t
f
r
o
m
p
lai
n
tex
t
w
it
h
i
n
t
h
e
k
n
o
w
led
g
e
to
w
ar
d
s
en
cr
y
p
ti
n
g
k
e
y
Hen
ce
,
t
h
ese
t
w
o
co
n
d
itio
n
s
m
u
s
t
b
e
s
a
tis
f
ied
e
v
en
w
h
ic
h
t
h
e
d
ec
r
y
p
tio
n
a
n
d
en
cr
y
p
tio
n
alg
o
r
ith
m
s
ar
e
k
n
o
w
n
.
I
n
ad
d
itio
n
,
t
h
e
s
y
m
m
etr
ic
cr
y
p
to
g
r
ap
h
y
i
s
r
ef
er
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ed
as
th
e
cr
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p
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g
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ap
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ic
s
y
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te
m
w
h
er
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th
e
s
a
m
e
o
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th
e
s
i
m
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lie
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th
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p
u
r
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o
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e
o
f
d
ec
r
y
p
tio
n
o
r
en
cr
y
p
tio
n
[
1
7
,
1
8
]
.
I
n
t
h
e
s
y
m
m
etr
ic
cr
y
p
to
s
y
s
te
m
,
t
h
e
co
m
m
u
n
i
ca
tio
n
en
titi
es
s
h
ar
e
th
e
s
ec
r
et
k
e
y
w
h
ic
h
i
s
s
i
m
ila
r
in
n
a
tu
r
e
[
19
].
T
h
e
as
y
m
m
etr
ic
is
th
e
p
u
b
lic
k
e
y
w
h
ich
is
u
s
ed
in
th
e
cr
y
p
to
g
r
ap
h
y
s
y
s
te
m
t
h
at
i
n
cl
u
d
es
th
e
p
air
o
f
k
e
y
s
.
I
t
in
cl
u
d
es
p
r
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a
n
d
p
u
b
lic
k
e
y
w
h
er
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t
h
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u
b
lic
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is
tr
ib
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ted
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u
t
t
h
e
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ate
k
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m
ai
n
s
s
ec
r
et
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y
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e
e
n
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n
ce
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h
er
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ar
e
t
w
o
v
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t
y
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d
e
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ec
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tio
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n
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en
cr
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p
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o
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d
ata
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h
ile
t
h
e
r
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s
t te
ch
n
o
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o
n
l
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e
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er
ate
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d
v
alid
ate
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h
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d
ig
ital
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ig
n
at
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r
e.
T
h
e
aim
o
f
t
h
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s
r
esear
ch
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to
ex
a
m
in
e
w
a
y
s
b
y
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h
ic
h
th
e
t
elec
o
m
m
u
n
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n
n
et
w
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r
k
s
e
cu
r
it
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ca
n
b
e
en
h
an
ce
d
w
it
h
i
n
t
h
e
4
G
an
d
5
G
L
T
E
n
et
w
o
r
k
.
B
ased
o
n
th
is
t
h
e
o
b
j
ec
tiv
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ar
e:
a.
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o
ex
p
lo
r
e
th
e
co
n
ce
p
t o
f
cr
y
p
to
g
r
ap
h
y
i
n
telec
o
m
m
u
n
icati
o
n
n
et
w
o
r
k
s
ec
u
r
it
y
b.
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o
ex
p
l
o
r
e
th
e
in
f
o
r
m
atio
n
ab
o
u
t
cr
y
p
to
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ap
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ased
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r
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ls
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s
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y
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m
m
u
n
i
ca
tio
n
n
et
w
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r
k
f
o
r
s
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u
r
it
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r
p
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s
e
c.
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o
d
eter
m
i
n
e
th
e
I
m
p
ac
t o
f
cr
y
p
to
g
r
ap
h
icall
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o
n
s
ec
u
r
it
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i
n
4
G
an
d
5
G
L
T
E
n
et
w
o
r
k
s
2.
RE
S
E
ARCH
M
E
T
H
O
D
T
h
e
p
a
p
er
p
r
esen
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th
e
e
m
p
ir
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in
f
o
r
m
atio
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o
n
telec
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m
m
u
n
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n
et
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r
k
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ec
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r
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th
r
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cr
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4
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a
n
d
5
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L
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n
et
w
o
r
k
s
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T
h
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p
ap
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f
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s
ed
o
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p
r
i
m
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s
ec
o
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ar
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E
r
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Hu
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[
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2
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]
.
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RE
F
E
R
E
NC
E
S
[1
]
L
.
M
e
rrien
,
e
t
a
l
.
,
“
S
y
ste
m
a
n
d
m
e
th
o
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f
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u
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g
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p
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s
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c
u
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y
c
o
m
p
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t
a
n
d
a
m
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b
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e
tele
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o
m
m
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n
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ti
o
n
s
d
e
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Pa
ten
t
N
o
.
:
U
S
9
,
6
4
7
,
9
8
4
B,
2
0
1
7
.
[2
]
A
.
Ra
sh
id
,
e
t
a
l
.
,
“
S
c
o
p
in
g
t
h
e
c
y
b
e
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c
u
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y
b
o
d
y
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k
n
o
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led
g
e
,
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IEE
E
S
e
c
u
rity
&
Priva
c
y
,
v
ol
.
1
6
,
p
p
.
96
-
1
0
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,
2
0
1
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.
[3
]
G
.
P
a
re
k
h
,
et
al
.
,
“
Id
e
n
ti
fy
in
g
Co
re
Co
n
c
e
p
ts
o
f
C
y
b
e
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u
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y
:
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e
su
lt
s
o
f
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lp
h
i
P
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e
ss
e
s,
”
IEE
E
T
ra
n
sa
c
ti
o
n
s
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Ed
u
c
a
ti
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n
,
v
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l.
6
1
,
p
p
.
11
-
20
,
2
0
1
7
.
[4
]
N.
F
e
rg
u
so
n
,
e
t
a
l
.
,
“
Cry
p
to
g
ra
p
h
y
En
g
in
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rin
g
:
De
sig
n
P
rin
c
ip
les
a
n
d
P
ra
c
ti
c
a
l
A
p
p
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ti
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n
s,
”
Ne
w
Yo
rk
:
Jo
h
n
W
il
e
y
a
n
d
S
o
n
,
2
0
1
0
.
[5
]
M
.
M
o
sc
a
,
“
Cy
b
e
rse
c
u
rit
y
in
a
n
Era
w
it
h
Qu
a
n
t
u
m
Co
m
p
u
ters
:
W
il
l
W
e
Be
Re
a
d
y
?
”
IEE
E
S
e
c
u
rity
&
Priva
c
y
,
v
o
l.
1
6
,
p
p
.
3
8
-
4
1
,
2
0
1
8
.
[6
]
A
.
Jo
h
n
,
e
t
a
l
.
,
“
Ov
e
rsi
m
p
li
fy
in
g
q
u
a
n
t
u
m
fa
c
to
rin
g
,
”
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tu
re
,
v
o
l.
499
,
p
p
.
1
6
3
-
1
6
5
,
2
0
1
3
.
[7
]
R.
T
.
P
e
l
ti
e
r,
“
In
f
o
rm
a
ti
o
n
S
e
c
u
rit
y
P
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li
c
ies
,
P
ro
c
e
d
u
re
s,
a
n
d
S
tan
d
a
rd
s:
G
u
id
e
li
n
e
s
f
o
r
Ef
f
e
c
ti
v
e
In
f
o
r
m
a
ti
o
n
S
e
c
u
rit
y
M
a
n
a
g
e
m
e
n
t
,
”
CRC P
re
ss
,
2
0
1
3
.
[8
]
Y
.
Ch
o
i
,
e
t
a
l
.,
“
S
e
c
u
ri
ty
En
h
a
n
c
e
d
Us
e
r
A
u
th
e
n
ti
c
a
ti
o
n
P
r
o
t
o
c
o
l
f
o
r
W
irele
ss
S
e
n
so
r
Ne
t
w
o
rk
s
Us
in
g
El
li
p
ti
c
Cu
rv
e
s Cr
y
p
to
g
ra
p
h
y
,
”
S
e
n
so
rs
(Ba
se
l)
,
v
o
l.
1
4
,
p
p
.
1
0
0
8
1
-
1
0
1
0
6
,
2
0
1
4
.
[9
]
K.
M
.
A
b
d
u
ll
a
h
,
e
t
a
l
.
,
“
Ne
w
S
e
c
u
rit
y
P
ro
to
c
o
l
u
sin
g
Hy
b
rid
Cr
y
p
to
g
ra
p
h
y
A
l
g
o
rit
h
m
f
o
r
W
S
N
,
”
1
s
t
In
ter
n
a
ti
o
n
a
l
Co
n
fer
e
n
c
e
o
n
Co
m
p
u
ter
A
p
p
li
c
a
ti
o
n
s &
In
fo
rm
a
ti
o
n
S
e
c
u
rity
,
IEE
E
ICCAIS
2
0
1
8
.
p
p
.
1
-
6
,
2
0
1
8
.
[1
0
]
T
.
Bin
,
e
t
a
l
.
,
“
A
se
c
u
rit
y
f
ra
m
e
w
o
rk
f
o
r
w
irele
s
s
se
n
so
r
n
e
tw
o
rk
s
,
”
T
h
e
J
o
u
rn
a
l
o
f
Ch
in
a
Un
ive
rs
it
i
e
s
o
f
P
o
sts
a
n
d
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n
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,
v
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l.
1
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p
p
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2
2
,
2
0
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0
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[1
1
]
R.
Rizk
,
e
t
a
l
.
,
“
Tw
o
-
p
h
a
se
h
y
b
rid
c
r
y
p
to
g
ra
p
h
y
a
l
g
o
rit
h
m
f
o
r
w
irele
ss
s
e
n
so
r
n
e
tw
o
rk
s,
”
J
o
u
rn
a
l
o
f
El
e
c
trica
l
S
y
ste
ms
a
n
d
In
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o
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ti
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n
T
e
c
h
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g
y
,
v
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l
.
2
,
p
p
.
2
9
6
-
3
1
3
,
2
0
1
5
.
[1
2
]
X
.
G
u
o
-
bo
a
n
d
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.
L
o
n
g
,
“
El
li
p
ti
c
-
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rv
e
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se
d
S
e
c
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rit
y
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ro
c
e
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o
r
f
o
r
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ID
,
”
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n
s
a
c
ti
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n
s
o
n
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m
p
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ter
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3
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4
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[1
5
]
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.
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leh
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a
l
.
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6
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7
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[1
8
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.
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9
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M
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0
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B.
C.
Ne
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“
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.
33
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9
4
.
[2
1
]
S
.
M
.
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ll
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l
.
,
“
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im
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4
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ss
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ro
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g
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g
,
A
p
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d
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c
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c
e
P
riv
e
t
Un
iv
e
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y
,
Am
m
a
n
,
Jo
rd
a
n
.
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c
u
rre
n
t
re
se
a
rc
h
in
tere
sts in
c
lu
d
e
CM
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h
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h
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.
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ti
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ra
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ra
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ro
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t
Al
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lq
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Ap
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Un
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s
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m
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d
M
icro
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ss
o
rs.
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a
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d
a
t
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.
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a
sa
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h
wa
s
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r
n
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p
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8
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rd
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n
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c
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p
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rtme
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a
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lt
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g
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g
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u
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rd
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n
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h
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d
a
m
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ste
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o
m
m
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En
g
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g
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ro
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th
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f
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rd
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n
in
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rre
n
tl
y
,
a
P
h
.
D.
stu
d
e
n
t
a
t
Ch
in
a
Un
iv
e
rsity
o
f
Ge
o
sc
ien
c
e
s
(W
u
h
a
n
).
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e
a
rc
h
in
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n
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lu
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e
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ig
it
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l
w
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o
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ti
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s,
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IM
O Rad
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r
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n
d
Ev
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ti
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ry
A
lg
o
rit
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m
s
Dr
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s
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n
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rtme
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a
c
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lt
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o
f
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g
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rin
g
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n
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T
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c
h
n
o
l
o
g
y
,
A
l
-
Ba
lq
a
’
A
p
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d
Un
iv
e
rsity
,
Jo
rd
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n
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Al
-
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s
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e
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h
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n
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n
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2
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l
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Dr.
Aw
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r
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l
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D
ig
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n
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m
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w
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n
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rk
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se
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n
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