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p
r
o
to
co
l
n
ev
er
th
ele
s
s
r
ec
k
o
n
o
n
ap
p
licatio
n
s
p
ec
if
ic
i
m
p
le
m
e
n
tatio
n
[
8
]
.
Mo
b
ile
p
a
y
m
e
n
t
ac
ce
p
ta
n
c
e
b
y
u
s
er
s
w
h
e
n
co
r
r
elate
d
to
o
th
er
tr
ad
itio
n
a
l
m
et
h
o
d
s
o
f
p
a
y
m
en
t
is
lo
w
a
s
d
ef
ici
t
o
f
u
s
er
tr
u
s
t
p
la
y
s
a
ca
r
d
in
al
r
o
le
in
p
a
y
m
e
n
t
i
n
d
u
s
tr
y
[
1
3
]
,
[
1
4
]
.
T
h
e
m
o
b
ile
p
h
o
n
es
ar
e
s
u
s
ce
p
tib
le
to
v
ar
io
u
s
s
ec
u
r
it
y
t
h
r
ea
ts
as
it
co
n
tain
s
s
e
n
s
it
iv
e
d
ata
o
f
p
ay
m
e
n
t
u
s
er
s
.
T
h
e
s
en
s
iti
v
e
d
ata
m
a
y
co
n
tai
n
p
er
s
o
n
al
in
f
o
r
m
at
io
n
o
r
p
ay
m
en
t
cr
ed
en
tial
s
o
f
th
e
u
s
er
s
.
T
h
er
ef
o
r
e,
to
s
ec
u
r
e
s
en
s
iti
v
e
d
ata
m
u
lti
f
ac
to
r
au
t
h
e
n
ticatio
n
tech
n
iq
u
e
s
ca
n
b
e
f
an
cied
[
1
5
]
.
A
cc
e
s
s
ib
ilit
y
an
d
Sec
u
r
it
y
ar
e
t
w
o
f
ac
to
r
s
w
h
is
h
p
er
s
u
ad
e
th
e
u
s
er
s
to
u
s
e
th
eir
s
m
ar
t
p
h
o
n
es
f
o
r
co
n
d
u
cti
n
g
f
i
n
a
n
cial
tr
a
n
s
ac
ti
o
n
s
[
1
6
]
,
[
1
7
]
.
T
h
e
in
itiato
r
an
d
th
e
tar
g
et
u
s
er
s
o
f
elec
tr
o
n
ic
b
an
k
i
n
g
s
y
s
te
m
in
v
o
l
v
ed
in
tr
an
s
ac
tio
n
e
x
ec
u
tio
n
n
ee
d
d
eter
m
i
n
ed
id
en
t
if
i
ca
tio
n
.
T
h
e
k
e
y
i
s
s
u
es
lik
e
s
e
cu
r
it
y
,
p
r
iv
ac
y
a
n
d
au
th
e
n
tica
tio
n
f
o
r
s
ec
u
r
in
g
b
an
k
i
n
g
tr
an
s
ac
tio
n
s
ar
e
n
ec
es
s
ar
y
to
b
e
f
ath
o
m
[
1
8
]
.
W
ith
r
esp
ec
t
to
s
ec
u
r
e
m
o
b
ile
p
a
y
m
e
n
t
s
er
v
ice,
Ka
d
am
b
i
et
a
l.
d
escr
ib
ed
a
NF
C
-
b
ased
m
o
b
ile
p
a
y
m
en
t
s
o
l
u
tio
n
;
it
eli
m
i
n
ate
s
tr
an
s
m
is
s
io
n
o
f
s
e
n
s
i
tiv
e
in
f
o
r
m
atio
n
o
v
er
th
e
n
et
w
o
r
k
s
u
c
h
as
P
A
N
an
d
P
I
N
[
2
]
.
E
n
d
to
E
n
d
en
cr
y
p
tio
n
tech
n
iq
u
es
f
o
s
ter
t
h
e
s
e
n
s
iti
v
e
d
ata
in
m
o
b
ile
p
a
y
m
en
t s
y
s
te
m
[
1
9
]
.
3.
S
E
CUR
I
T
Y
ASS
AY
O
F
NF
C
-
E
NAB
L
E
D
M
O
B
I
L
E
P
AYM
E
NT
SYS
T
E
M
T
h
e
m
o
b
ile
p
a
y
m
e
n
ts
u
s
i
n
g
NFC
n
ee
d
e
v
o
lv
e
m
e
n
t
o
f
cr
y
p
to
g
r
ap
h
ic
p
r
o
to
co
ls
i
n
f
u
r
t
h
er
an
ce
o
f
r
ec
o
n
cilin
g
th
e
d
esire
s
ec
u
r
it
y
r
eq
u
ir
em
e
n
t
s
.
T
h
e
s
ec
u
r
it
y
an
al
y
s
i
s
o
f
NF
C
-
e
n
ab
led
m
o
b
ile
p
ay
m
en
t
s
y
s
te
m
i
s
p
r
ec
ar
io
u
s
l
y
i
m
p
er
ati
v
e
d
u
e
to
its
w
id
e
s
p
r
ea
d
r
atif
icatio
n
.
T
h
e
NFC
tech
n
o
lo
g
y
b
y
v
ir
t
u
e
o
f
w
ir
eles
s
n
at
u
r
e
is
s
u
s
ce
p
tib
le
to
ea
v
esd
r
o
p
p
in
g
.
I
t
is
f
u
tile
to
h
ar
b
o
r
ac
r
o
s
s
ea
v
esd
r
o
p
p
in
g
in
NF
C
tec
h
n
o
lo
g
y
w
it
h
o
u
t
t
h
e
u
s
e
o
f
en
cr
y
p
t
io
n
,
s
o
l
u
tio
n
i
s
to
s
e
tu
p
a
s
ec
u
r
e
ch
a
n
n
e
l.
Data
en
c
r
y
p
tio
n
i
n
m
o
b
ile
p
a
y
m
e
n
t
i
m
p
ar
ts
s
ec
u
r
i
n
g
d
at
a
an
d
r
ev
italizes
m
o
b
ile
p
a
y
m
e
n
t
ad
o
p
tio
n
.
Du
r
in
g
d
ata
in
tr
a
n
s
it,
m
o
d
i
f
icatio
n
to
th
e
tr
an
s
ac
tio
n
d
ata
g
r
o
u
n
d
s
s
ec
u
r
it
y
th
r
ea
t
s
in
m
o
b
ile
p
a
y
m
en
t s
y
s
te
m
.
T
h
e
clo
v
er
o
f
m
o
b
ile
p
a
y
m
en
ts
r
ec
k
o
n
s
o
n
f
ac
to
r
s
l
ik
e
s
ec
u
r
it
y
,
f
ait
h
,
co
n
f
id
en
tialit
y
a
n
d
au
th
e
n
tic
it
y
.
Sec
u
r
it
y
a
n
d
R
eliab
ilit
y
ar
e
th
e
ess
e
n
tial
f
ac
to
r
s
r
eq
u
ir
ed
f
o
r
NFC
tech
n
o
lo
g
y
p
lacid
to
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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2
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8
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I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
8
,
No
.
3
,
J
u
n
e
2
0
1
8
:
1
7
7
4
–
1780
1776
u
n
d
er
s
ta
n
d
p
r
ev
alen
t
r
ati
f
icati
o
n
.
T
o
s
af
eg
u
ar
d
co
n
f
id
en
tia
l
it
y
,
cr
y
p
to
g
r
ap
h
ic
m
ec
h
a
n
i
s
m
ca
n
b
e
u
s
ed
.
T
h
e
cr
y
p
t
o
g
r
ap
h
ic
k
e
y
m
a
n
ag
e
m
e
n
t
f
o
r
f
e
n
d
th
e
m
o
b
ile
p
a
y
m
e
n
t
s
y
s
te
m
’
s
s
e
n
s
iti
v
e
d
ata
f
r
o
m
th
e
attac
k
er
s
[
2
0
]
.
I
n
t
h
e
t
h
r
ea
t
m
o
d
el
t
h
e
en
cr
y
p
ted
m
es
s
ag
e
ca
n
n
o
t
b
e
en
cr
y
p
ted
w
it
h
o
u
t
d
ec
r
y
p
tio
n
k
e
y
th
er
eb
y
p
r
ev
e
n
ti
n
g
th
e
attac
k
er
f
r
o
m
p
er
f
o
r
m
in
g
a
n
y
cr
y
p
ta
n
al
y
s
i
s
.
Su
s
ce
p
tib
il
it
y
o
f
t
h
e
p
a
y
m
e
n
t
in
f
o
r
m
atio
n
in
m
o
b
ile
p
a
y
m
en
t
s
y
s
te
m
s
m
o
t
iv
ate
to
w
ar
d
s
s
ec
u
r
it
y
d
esig
n
.
T
h
e
s
ec
u
r
it
y
d
esi
g
n
r
ef
er
s
to
s
y
s
te
m
d
e
s
ig
n
a
s
f
r
e
e
o
f
s
u
s
ce
p
tib
le
n
ess
a
n
d
i
n
v
u
ln
er
ab
le
to
attac
k
f
ea
s
ib
le
t
h
r
o
u
g
h
s
ec
u
r
it
y
co
n
tr
o
ls
.
Mo
b
ile
p
ay
m
e
n
ts
e
n
d
ea
v
o
r
a
s
co
p
ic
r
an
g
e
o
f
s
ec
u
r
it
y
f
ac
et
n
ev
er
t
h
eles
s
,
it
is
th
e
u
s
er
w
h
o
n
ee
d
to
s
af
eg
u
ar
d
th
eir
d
ata.
T
h
er
ef
o
r
e,
th
is
ca
n
b
e
co
n
s
u
m
m
ated
b
y
u
s
i
n
g
f
o
llo
w
i
n
g
k
n
o
w
led
g
e.
a.
Usi
n
g
u
n
iq
u
e
an
d
s
tr
o
n
g
p
ass
w
o
r
d
b.
Up
d
atin
g
a
n
ti
-
v
ir
u
s
s
o
f
t
w
ar
e
c.
Usi
n
g
m
u
lti
f
ac
to
r
au
t
h
en
t
icati
o
n
d.
E
n
cr
y
p
tio
n
o
f
s
en
s
iti
v
e
d
ata
e.
Hav
i
n
g
r
e
m
o
te
d
ata
w
ip
e
f
ac
il
it
y
i
n
m
o
b
ile
p
h
o
n
e
T
h
e
in
n
u
m
er
ab
le
tr
an
s
ac
tio
n
s
ec
u
r
it
y
is
th
e
p
r
o
m
in
e
n
t
i
t
is
f
o
r
all
th
e
e
n
tit
ies
i
n
v
o
lv
ed
i
n
t
h
e
m
o
b
il
e
p
ay
m
e
n
t s
y
s
te
m
.
As NF
C
is
a
p
u
llu
la
tin
g
tec
h
n
o
lo
g
y
,
c
u
tti
n
g
-
ed
g
e
m
o
b
ile
p
a
y
m
e
n
t
m
eth
o
d
s
w
il
l p
r
ef
ac
e
n
e
w
th
r
ea
ts
/r
i
s
k
s
.
C
o
n
s
u
m
er
s
h
o
u
l
d
en
s
u
e
s
ec
u
r
it
y
m
ea
s
u
r
es
li
k
e
u
p
d
atin
g
o
p
er
atin
g
s
y
s
te
m
o
n
a
r
eg
u
lar
b
asis
w
h
e
n
p
r
o
v
id
ed
b
y
OS
p
r
o
v
id
er
,
n
o
t
u
s
in
g
p
u
b
lic
W
i
-
Fi
f
o
r
m
a
k
i
n
g
p
a
y
m
en
ts
,
u
s
i
n
g
m
u
lti
f
ac
to
r
au
th
e
n
tica
tio
n
to
th
e
m
o
b
ile
p
h
o
n
e
an
d
in
c
ase
o
f
d
ev
ice
lo
s
t/s
to
le
n
h
a
v
i
n
g
r
e
m
o
te
d
ata
w
ip
e
f
ac
i
lit
y
i
n
th
e
m
o
b
ile
p
h
o
n
e.
Au
t
h
en
t
icatio
n
an
d
Au
t
h
o
r
izatio
n
is
cr
itic
f
o
r
m
o
b
ile
p
a
y
m
en
t
s
y
s
te
m
b
ec
au
s
e
it
a
u
t
h
en
t
icate
s
t
h
e
co
n
s
u
m
er
a
n
d
a
u
t
h
o
r
izes
t
h
e
p
ay
m
e
n
t
tr
an
s
ac
tio
n
.
I
f
th
er
e
i
s
p
r
o
n
en
e
s
s
in
a
u
th
o
r
izatio
n
,
t
h
en
it
m
ig
h
t
lead
to
i
m
p
er
s
o
n
atio
n
attac
k
.
Sec
u
r
it
y
o
f
m
o
b
ile
p
a
y
m
en
t
is
v
i
tal
as
it
af
f
ec
ts
t
h
e
d
if
f
er
en
t
e
n
tit
ies
in
t
h
e
p
a
y
m
e
n
t
s
y
s
te
m
.
I
n
m
o
b
ile
p
a
y
m
e
n
t s
y
s
te
m
s
ec
u
r
it
y
t
h
r
ea
ts
ar
e
co
g
n
ate
to
th
e
b
u
s
i
n
es
s
d
ata
in
tr
an
s
it o
r
d
ata
at
r
est.
In
co
n
s
eq
u
e
n
ce
,
th
e
s
t
u
d
y
h
a
s
b
ee
n
ad
m
in
is
ter
ed
to
h
o
w
t
h
e
m
o
b
ile
p
a
y
m
en
t
s
y
s
te
m
ca
n
b
e
m
ad
e
s
ec
u
r
e
an
d
r
eliab
le
f
o
r
th
e
co
n
s
u
m
er
s
to
u
s
e.
C
o
n
s
u
m
er
ed
u
ca
tio
n
an
d
k
n
o
w
led
g
e
is
a
s
ar
ca
s
tic
f
ac
et
in
s
ec
u
r
i
n
g
m
o
b
ile
p
a
y
m
en
t
s
.
C
o
n
s
id
er
in
g
p
er
v
a
s
i
v
e
u
s
ag
e
an
d
ad
o
p
tio
n
o
f
m
o
b
ile
p
ay
m
e
n
t
s
er
v
ice
s
f
o
r
co
n
s
u
m
er
’
s
s
ec
u
r
it
y
,
p
r
iv
ac
y
,
tr
u
s
t
a
n
d
r
eliab
ilit
y
s
h
o
u
ld
b
e
i
m
m
en
s
e.
Fo
r
an
y
s
ec
u
r
e
m
o
b
ile
p
a
y
m
e
n
t
s
y
s
te
m
co
n
f
id
e
n
tialit
y
,
au
t
h
e
n
ticatio
n
,
in
teg
r
it
y
a
n
d
n
o
n
-
r
ep
u
d
iatio
n
s
h
o
u
ld
b
e
en
d
o
r
s
ed
[
2
1
]
.
T
o
k
en
iza
tio
n
,
u
s
er
an
d
de
v
ice
au
th
e
n
tica
tio
n
an
d
wh
iteb
o
x
cr
y
p
to
g
r
ap
h
y
w
h
e
n
co
m
b
i
n
ed
in
s
y
n
c
f
o
r
m
s
a
f
l
a
w
le
s
s
s
o
l
u
tio
n
f
o
r
d
ef
en
d
i
n
g
m
o
b
ile
p
a
y
m
en
t
s
y
s
te
m
s
.
I
n
m
o
b
ile
p
a
y
m
en
ts
s
ec
u
r
it
y
i
s
a
p
r
ev
alen
t
co
n
ce
r
n
b
y
v
ir
tu
e
o
f
th
e
f
in
a
n
cial
v
al
u
e
at
s
ta
v
e.
Mo
b
ile
p
ay
m
e
n
ts
ar
e
s
ec
u
r
e
i
f
t
h
e
u
s
er
an
d
d
ev
ice
id
en
tific
atio
n
b
i
n
d
to
t
h
e
tr
an
s
ac
t
io
n
a
u
t
h
o
r
izatio
n
[
2
2
]
.
W
h
en
a
n
attac
k
er
attac
k
s
t
h
e
m
o
b
ile
p
a
y
m
e
n
t
ap
p
licatio
n
,
lo
o
k
s
f
o
r
t
h
e
p
a
y
m
e
n
t
cr
ed
en
tials
,
cr
y
p
t
o
g
r
ap
h
y
k
e
y
s
.
Si
n
ce
th
e
to
k
e
n
s
tr
av
el
o
v
er
th
e
p
ay
m
e
n
t
n
et
w
o
r
k
,
i
f
m
ad
e
m
a
n
i
f
est
t
h
e
attac
k
er
ca
n
r
eq
u
e
s
t
f
o
r
a
n
e
w
to
k
e
n
g
en
er
atio
n
,
m
a
n
-
i
n
–
th
e
-
m
id
d
le
attac
k
tar
g
e
ts
t
h
e
p
a
y
m
e
n
t
a
p
p
licatio
n
r
esid
in
g
i
n
th
e
m
o
b
ile
p
h
o
n
e
o
p
er
atin
g
s
y
s
te
m
.
T
h
er
ef
o
r
e,
it is
i
m
p
er
a
tiv
e
to
co
n
g
ea
l th
e
ap
p
licatio
n
to
p
r
o
tect
f
ac
in
g
t
h
is
t
y
p
e
o
f
a
ttack
.
T
h
e
attac
k
er
g
ain
s
r
o
o
t
ac
ce
s
s
o
f
th
e
m
o
b
il
e
p
h
o
n
e
an
d
lo
o
k
s
at
t
h
e
p
a
y
m
en
t
ap
p
licatio
n
co
d
e
f
o
r
cr
iti
ca
l
in
f
o
r
m
atio
n
li
k
e
p
ay
m
e
n
t
cr
ed
en
t
ials
o
r
cr
y
p
to
g
r
ap
h
y
k
e
y
s
.
Ho
w
e
v
er
,
t
h
e
to
k
en
p
ass
es
th
r
o
u
g
h
t
h
e
p
a
y
m
en
t
n
et
w
o
r
k
m
a
k
es
u
s
e
o
f
s
tan
d
ar
d
p
r
o
to
co
ls
lik
e
SS
L
/
T
L
S
.
T
h
e
cr
ea
tio
n
o
f
t
h
e
s
u
r
r
o
g
ate
id
en
ti
f
ier
is
v
er
y
ea
s
y
as
co
m
in
g
u
p
w
i
th
r
a
n
d
o
m
s
tr
in
g
n
u
m
b
er
s
t
h
at
ca
n
b
e
m
a
tch
ed
u
p
b
ac
k
to
t
h
e
o
r
ig
in
al
s
tr
i
n
g
.
Hen
ce
to
k
e
n
izatio
n
eli
m
i
n
ates
t
h
e
n
ee
d
f
o
r
p
ay
m
en
t
s
er
v
ice
p
r
o
v
id
er
,
m
er
ch
a
n
t
’
s
a
n
d
e
-
co
m
m
er
ce
s
ites
to
s
to
r
e
s
e
n
s
i
tiv
e
p
ay
m
e
n
t c
ar
d
d
ata
o
n
th
eir
n
e
t
w
o
r
k
s
.
3
.
1
.
Securit
y
t
ec
hn
iqu
e
s
in
m
o
b
il
e
pa
y
m
ent
s
Mo
b
ile
b
an
k
i
n
g
ap
p
licatio
n
n
ee
d
a
s
ec
u
r
e
e
n
v
ir
o
n
m
e
n
t
as
th
e
y
p
r
o
ce
s
s
s
e
n
s
i
tiv
e
d
a
ta.
As
th
e
ap
p
licatio
n
r
eq
u
ir
es
p
r
o
ce
s
s
in
g
an
d
s
to
r
in
g
s
e
n
s
iti
v
e
d
ata
it
p
ilo
ts
to
th
e
g
r
o
w
t
h
o
f
s
ec
u
r
e
en
v
ir
o
n
m
e
n
t
s
[
2
3
]
.
T
h
e
s
ec
u
r
it
y
m
et
h
o
d
s
w
h
ic
h
c
an
b
e
en
f
o
r
ce
d
in
t
h
e
m
o
b
ile
p
a
y
m
e
n
t a
p
p
licatio
n
s
ar
e
:
a.
I
n
m
o
b
ile
p
a
y
m
e
n
ts
it
i
s
i
m
p
e
r
ativ
e
to
id
en
ti
f
y
t
h
e
u
s
er
as
a
u
th
o
r
ized
u
s
er
o
f
t
h
e
m
o
b
ile
p
a
y
m
e
n
t
s
y
s
te
m
.
T
h
e
g
en
er
al
m
et
h
o
d
s
f
o
r
u
s
er
id
en
ti
f
ica
tio
n
ar
e
s
o
f
t
to
k
en
,
b
io
m
etr
ic
li
k
e
u
s
e
r
f
in
g
er
p
r
in
t
i
s
co
m
m
e
n
s
u
r
ab
le
[
2
2
]
.
b.
T
h
e
g
o
al
o
f
to
k
en
izatio
n
p
r
o
ce
s
s
is
to
r
ep
lace
th
e
s
en
s
iti
v
e
P
A
N
v
alu
e
w
it
h
n
o
n
-
s
en
s
iti
v
e
to
k
en
v
alu
e
[
2
2
]
.
B
y
r
ep
lacin
g
s
e
n
s
iti
v
e
d
ata
w
it
h
s
u
r
r
o
g
ate
id
en
tifie
r
t
h
e
u
s
er
is
en
s
u
r
i
n
g
t
h
at
if
a
n
y
h
ac
k
er
r
ec
ei
v
e
s
th
is
in
f
o
r
m
at
io
n
,
w
ill
b
e
u
n
ab
le
to
u
s
e
i
t
f
o
r
an
y
p
u
r
p
o
s
e.
T
h
e
s
ec
u
r
it
y
o
f
a
n
i
n
d
iv
id
u
al
to
k
en
d
ep
en
d
s
o
n
th
e
u
n
iq
u
e
n
e
s
s
an
d
t
h
e
in
f
ea
s
i
b
ilit
y
d
eter
m
i
n
es t
h
e
o
r
ig
i
n
al
P
A
N
k
n
o
w
i
n
g
o
n
l
y
t
h
e
s
u
r
r
o
g
ate
v
alu
e.
c.
T
h
e
s
en
s
i
tiv
e
d
ata
ca
n
b
e
s
t
o
r
ed
o
n
th
e
clo
u
d
a
n
d
ca
n
b
e
p
r
o
cu
r
ed
b
y
u
s
i
n
g
m
o
b
ile
ap
p
licatio
n
s
.
I
n
to
k
en
izat
io
n
p
r
o
ce
s
s
,
th
e
to
k
e
n
g
e
n
er
atio
n
an
d
ca
ch
i
n
g
ca
n
b
e
ac
co
m
p
lis
h
ed
in
th
e
clo
u
d
.
No
n
eth
eles
s
,
it
is
m
a
n
d
ato
r
y
to
s
ec
u
r
e
t
h
e
a
u
th
o
r
izatio
n
ac
ce
s
s
to
th
e
cl
o
u
d
s
er
v
er
f
o
r
th
is
r
ea
s
o
n
;
u
s
er
an
d
d
ev
ice
au
th
e
n
tica
tio
n
s
h
o
u
ld
b
e
co
n
s
u
m
m
ated
.
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:
2
0
8
8
-
8708
Th
e
F
a
ct
-
F
in
d
in
g
S
ec
u
r
ity
E
xa
min
a
tio
n
in
N
F
C
-
en
a
b
led
M
o
b
ile
P
a
yme
n
t
…
(
P
in
ki
P
r
a
ka
s
h
V
is
h
w
a
ka
r
ma
)
1777
d.
T
h
esen
s
it
iv
e
d
ata
is
m
ai
n
tai
n
ed
w
it
h
en
cr
y
p
tio
n
a
n
d
d
ec
r
y
p
tio
n
o
p
er
atio
n
s
w
i
th
o
u
t
r
ev
ea
li
n
g
th
e
cr
y
p
to
g
r
ap
h
y
k
e
y
s
an
d
t
h
e
s
e
n
s
it
iv
e
d
ata.
A
m
ea
n
s
f
o
r
p
r
o
tectin
g
th
e
cr
y
p
to
g
r
ap
h
ic
o
p
er
atio
n
s
an
d
t
h
e
d
ata
is
w
h
iteb
o
x
cr
y
p
to
g
r
ap
h
y
.
W
ith
th
e
w
h
i
teb
o
x
cr
y
p
to
g
r
ap
h
y
[
2
4
]
th
e
attac
k
er
ca
n
n
o
t
d
ec
r
y
p
t
t
h
e
k
e
y
w
h
e
n
th
e
to
k
e
n
p
ass
e
s
f
r
o
m
th
e
s
ec
u
r
e
co
m
m
u
n
icatio
n
ch
an
n
el
;
n
eit
h
er
is
ab
le
to
in
j
ec
t
d
ata
in
to
th
e
ch
an
n
el
.
e.
T
h
e
d
ata
at
r
est
r
eq
u
ir
es
th
e
s
en
s
it
iv
e
d
ata
to
b
e
s
to
r
ed
s
ec
u
r
el
y
,
th
e
p
a
y
m
e
n
t
cr
ed
en
tial
s
o
f
th
e
p
a
y
m
e
n
t
u
s
er
s
s
h
o
u
ld
n
o
t
r
esid
e
o
n
th
e
m
o
b
ile
d
ev
ice.
T
h
e
s
en
s
it
iv
e
d
ata
o
f
th
e
u
s
er
s
is
e
n
cr
y
p
ted
an
d
s
to
r
ed
.
T
h
e
cr
y
p
to
g
r
ap
h
ic
k
e
y
s
u
s
ed
f
o
r
en
cr
y
p
tio
n
an
d
d
ec
r
y
p
tio
n
m
u
s
t
b
e
s
to
r
ed
s
ec
u
r
el
y
[
2
0
]
.
I
t
s
h
o
u
ld
b
e
r
elativ
el
y
d
if
f
ic
u
lt
f
o
r
t
h
e
atta
ck
er
to
k
n
o
w
t
h
e
cr
y
p
to
g
r
ap
h
i
c
k
e
y
s
a
n
d
th
e
en
cr
y
p
tio
n
/d
ec
r
y
p
tio
n
p
r
o
ce
s
s
.
T
h
e
alg
o
r
ith
m
s
u
s
ed
f
o
r
i
m
p
le
m
en
tin
g
e
n
cr
y
p
tio
n
an
d
d
ec
r
y
p
tio
n
p
r
o
ce
s
s
m
u
s
t
elu
d
e
t
h
e
a
ttack
er
,
leav
in
g
th
e
s
e
n
s
it
iv
e
d
ata
i
n
a
s
ec
u
r
e
s
tate.
f.
T
h
e
d
ata
in
tr
an
s
i
t r
eq
u
ir
es a
s
ec
u
r
e
co
m
m
u
n
icat
io
n
c
h
an
n
el
w
h
ic
h
ca
n
b
e
ac
co
m
p
li
s
h
ed
b
y
u
s
i
n
g
a
s
ec
u
r
e
co
m
m
u
n
icatio
n
p
r
o
to
co
l
b
et
w
ee
n
t
h
e
i
n
itiato
r
a
n
d
th
e
tar
g
et
u
s
er
.
I
n
m
o
b
ile
p
a
y
m
e
n
t
s
y
s
t
e
m
to
k
e
n
izat
io
n
an
d
d
ata
en
cr
y
p
tio
n
ar
e
ef
f
ec
ti
v
e
m
et
h
o
d
s
f
o
r
s
ec
u
r
in
g
d
ata
i
n
tr
an
s
it.
3
.
2
.
S
ec
ure
m
o
bil
e
pa
y
m
e
nt
t
ra
ns
a
ct
io
n
T
h
e
d
is
ce
r
n
m
en
t
an
d
k
n
o
w
led
g
e
o
f
s
ec
u
r
it
y
t
h
r
ea
ts
ar
e
s
u
b
s
t
an
tial
w
it
h
i
n
th
e
p
a
y
m
e
n
t
ec
o
s
y
s
te
m
.
A
p
ay
m
e
n
t
tr
an
s
ac
tio
n
i
s
af
o
r
es
aid
r
eliab
le
tr
an
s
ac
tio
n
w
h
en
th
e
au
t
h
e
n
ticit
y
o
f
t
h
e
en
t
iti
es
an
d
co
n
f
id
en
tia
l
in
f
o
r
m
atio
n
o
f
th
e
p
a
y
m
en
t
cr
ed
en
tials
v
an
q
u
is
h
.
I
t
is
i
m
p
er
ativ
e
to
p
r
o
tect
th
e
s
en
s
iti
v
e
d
ata
o
f
th
e
p
a
y
m
e
n
t
u
s
er
s
[
2
0
]
.
T
h
e
p
ay
m
e
n
t
in
f
o
r
m
atio
n
a
n
d
p
r
o
ce
s
s
o
n
N
FC
e
n
ab
led
m
o
b
ile
d
ev
ices
d
esire
t
h
e
a
m
al
g
a
m
atio
n
o
f
s
ec
u
r
it
y
tec
h
n
iq
u
e
s
a
n
d
p
r
o
to
co
ls
.
Sec
u
r
it
y
i
n
m
o
b
ile
p
a
y
m
en
t
s
is
a
p
r
i
m
e
co
n
ce
r
n
f
o
r
th
e
p
la
y
er
s
o
f
t
h
e
m
o
b
ile
p
a
y
m
en
t
s
y
s
te
m
,
co
n
s
u
m
er
s
,
m
er
ch
a
n
ts
an
d
t
h
e
p
ay
m
e
n
t
p
r
o
ce
s
s
o
r
s
.
T
o
b
esto
w
s
ec
u
r
e
m
o
b
ile
p
ay
m
e
n
t tr
an
s
ac
tio
n
,
it
s
h
o
u
ld
en
s
u
r
e
co
n
f
id
e
n
tiali
t
y
,
i
n
teg
r
i
t
y
,
au
t
h
e
n
ticatio
n
an
d
n
o
n
-
r
ep
u
d
iatio
n
[
1
6
]
,
[
2
1
]
.
a.
Sen
s
iti
v
e
p
a
y
m
e
n
t
d
ata
i
n
m
o
b
ile
p
ay
m
e
n
ts
s
h
o
u
ld
b
e
s
ec
u
r
ed
w
h
et
h
er
t
h
e
d
ata
is
in
tr
an
s
it
o
r
at
r
est
.
W
ith
al
en
d
-
to
-
e
n
d
en
cr
y
p
tio
n
tech
n
iq
u
e
is
u
s
ed
to
s
ec
u
r
e
p
ay
m
e
n
t
d
ata
to
ar
m
o
r
its
co
n
f
id
en
tial
it
y
a
n
d
in
te
g
r
it
y
.
C
o
n
f
id
en
t
ialit
y
o
f
p
a
y
m
e
n
t
i
n
f
o
r
m
atio
n
ca
n
al
s
o
b
e
p
r
eser
v
ed
th
r
o
u
g
h
to
k
e
n
iz
atio
n
p
r
o
ce
s
s
i
n
m
o
b
ile
p
a
y
m
e
n
t
s
y
s
te
m
.
T
h
e
t
r
an
s
ac
tio
n
d
ata
s
u
s
tain
ed
a
n
d
p
r
esen
ted
s
h
o
u
ld
b
e
p
r
ec
is
e
an
d
p
er
s
is
ten
t.
b.
Au
t
h
en
t
icatio
n
co
n
s
u
m
m
ate
t
h
r
o
u
g
h
u
s
er
p
ass
w
o
r
d
an
d
d
ev
ice
f
i
n
g
er
p
r
in
ts
.
Mu
tif
ac
to
r
au
th
e
n
ticatio
n
n
ee
d
to
b
e
d
ep
lo
y
ed
in
lieu
t
o
th
e
t
y
p
ical
P
I
N
f
o
r
m
o
b
ile
p
ay
m
e
n
ts
.
T
h
e
a
u
th
e
n
tica
tio
n
o
f
a
tr
an
s
ac
tio
n
u
s
i
n
g
m
o
b
ile
d
ev
ice
i
s
also
b
ased
o
n
th
e
co
n
s
u
m
er
b
eh
a
v
io
r
p
atter
n
.
c.
T
h
e
A
E
S e
n
cr
y
p
tio
n
tec
h
n
iq
u
e
ca
n
b
e
u
s
ed
f
o
r
s
ec
u
r
i
t
y
a
g
ai
n
s
t e
a
v
esd
r
o
p
p
in
g
a
n
d
d
ata
m
o
d
if
icatio
n
[
2
5
]
.
d.
I
n
m
o
b
ile
p
a
y
m
en
t
s
,
th
e
p
a
y
m
en
t
tr
an
s
ac
tio
n
s
ar
e
au
t
h
o
r
i
ze
d
u
s
in
g
SM
S
o
r
n
o
tif
icati
o
n
s
co
n
tai
n
i
n
g
p
ay
m
e
n
t
d
etails
a
n
d
tr
an
s
ac
tio
n
co
n
f
ir
m
at
io
n
is
s
en
t
to
p
a
y
e
e
an
d
p
ay
er
.
T
h
e
p
ay
m
e
n
t
tr
a
n
s
ac
tio
n
h
i
s
to
r
y
is
m
ai
n
tai
n
ed
f
o
r
f
u
t
u
r
e
in
v
est
ig
atio
n
.
A
l
lu
d
i
n
g
t
h
e
co
n
s
u
m
e
r
tr
an
s
ac
tio
n
h
is
to
r
y
a
n
d
th
e
s
p
en
d
in
g
p
atter
n
w
il
l le
s
s
e
n
t
h
e
r
is
k
o
f
f
r
a
u
d
u
le
n
t tr
an
s
ac
tio
n
[
2
6
]
.
3.
3
.
S
ec
urit
y
t
hrea
t
s
Secu
r
it
y
th
r
ea
t
s
an
d
attac
k
s
ai
m
th
e
m
o
b
ile
p
a
y
m
en
t s
y
s
te
m
th
er
eb
y
ca
u
s
i
n
g
f
i
n
an
c
ial
lo
s
s
[
1
6
]
.
a.
Usi
n
g
u
n
tr
u
s
ted
n
et
w
o
r
k
li
k
e
W
i
-
F
i
co
n
n
ec
tio
n
to
m
a
k
e
m
o
b
ile
p
a
y
m
e
n
ts
ca
n
ca
u
s
e
s
o
m
e
ac
c
id
en
ta
l
in
s
ta
llatio
n
o
f
f
r
au
d
ap
p
licati
o
n
o
n
th
e
m
o
b
ile
d
ev
ice,
f
a
ca
d
e
s
ec
u
r
it
y
r
is
k
f
o
r
th
e
co
n
s
u
m
er
m
o
b
ile
d
ev
ices.
J
ailb
r
ea
k
i
n
g
a
n
d
g
ain
in
g
r
o
o
t
ac
ce
s
s
o
f
m
o
b
ile
d
e
v
i
ce
ca
n
b
r
ea
k
t
h
e
d
e
f
au
l
t
s
ec
u
r
it
y
p
r
o
v
i
s
io
n
ed
b
y
t
h
e
m
o
b
ile
d
ev
ice
m
an
u
f
ac
tu
r
er
.
T
h
e
s
o
lu
tio
n
to
m
al
w
ar
e
th
r
ea
t
i
s
u
s
in
g
s
a
n
d
b
o
x
in
g
o
f
m
o
b
ile
ap
p
licatio
n
o
n
th
e
d
ev
ice.
b.
T
h
e
attac
k
er
m
o
d
if
ie
s
t
h
e
d
ata
th
at
is
b
ei
n
g
s
e
n
t
to
r
ea
d
er
d
ev
ice;
r
elin
q
u
is
h
t
h
e
d
ata
in
s
u
c
h
a
w
a
y
th
a
t
th
e
tr
an
s
ac
tio
n
is
n
o
t
s
u
cc
es
s
f
u
ll
y
ex
ec
u
ted
.
T
h
e
ex
p
licatio
n
to
th
is
a
ttack
is
to
estab
li
s
h
a
s
ec
u
r
e
c
h
an
n
el
b
et
w
ee
n
th
e
t
w
o
N
FC
d
ev
ice
s
i.e
.
in
itiato
r
d
ev
ice
an
d
tar
g
e
t d
ev
ice
an
d
u
s
in
g
a
s
ta
n
d
ar
d
k
e
y
p
r
o
to
co
l.
c.
L
o
s
i
n
g
th
e
NF
C
m
o
b
ile
p
h
o
n
e
w
il
l
b
e
an
ass
et
to
th
e
d
is
co
v
er
er
an
d
ca
n
co
n
s
titu
te
s
in
g
le
f
ac
to
r
au
th
e
n
tica
tio
n
.
T
h
e
attac
k
er
m
ak
e
s
e
f
f
o
r
t
to
b
y
p
ass
P
I
N
o
r
f
i
n
g
er
p
r
in
t
lo
c
k
s
.
I
t
ca
n
m
a
k
e
u
s
e
o
f
f
o
r
en
s
ic
to
o
ls
to
j
ailb
r
ea
k
th
e
m
o
b
ile
d
ev
ice
O
S
t
h
er
eb
y
,
g
ai
n
i
n
g
ac
ce
s
s
to
t
h
e
f
ile
s
y
s
te
m
to
s
teal
d
ata.
T
h
e
s
o
lu
tio
n
to
th
is
i
s
r
e
m
o
te
d
ata
w
ip
e
o
u
t.
d.
Desp
ite
o
f
h
a
v
i
n
g
a
s
ec
u
r
e
s
y
s
te
m
,
t
h
er
e’
s
al
w
a
y
s
a
m
ea
s
u
r
e
to
in
v
ad
e.
T
h
e
v
icti
m
n
o
d
e
ca
n
i
m
p
er
s
o
n
ate
a
g
en
u
i
n
e
n
o
d
e
as
a
r
es
u
lt
o
f
th
e
d
ef
ic
it
o
f
a
u
t
h
en
t
icatio
n
.
Au
t
h
en
ticatio
n
i
s
t
h
e
k
e
y
to
i
m
p
er
s
o
n
atio
n
attac
k
.
T
h
e
s
en
s
atio
n
o
f
u
s
er
id
en
tit
y
is
i
m
p
o
r
tan
t
s
o
it
is
i
m
p
er
ativ
e
to
al
w
a
y
s
au
t
h
e
n
ticate
t
h
e
u
s
e
r
id
en
tit
y
in
t
h
e
p
a
y
m
e
n
t s
y
s
te
m
.
4.
RE
SU
L
T
S AN
D
AN
AL
Y
SI
S
Viab
le
co
u
n
ter
m
ea
s
u
r
es a
r
e
b
esto
w
ed
i
n
th
is
s
ec
t
io
n
t
h
at
w
i
ll h
elp
to
ab
ate
th
e
se
cu
r
i
t
y
t
h
r
ea
ts
.
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
.
3
,
J
u
n
e
2
0
1
8
:
1
7
7
4
–
1780
1778
4
.
1
.
T
hrea
t
a
na
ly
s
is
in
m
o
bi
le
pa
y
m
ent
s
y
s
t
e
m
T
h
e
m
o
b
ile
p
a
y
m
e
n
t
m
o
d
el
p
lay
er
s
as
s
h
o
w
n
i
n
Fig
u
r
e
2
ar
e
th
e
m
o
b
ile
d
ev
ice,
P
OS,
p
ay
m
e
n
t
s
er
v
er
,
ac
q
u
ir
er
,
is
s
u
er
an
d
f
r
a
u
d
d
etec
tio
n
an
d
p
r
ev
en
tio
n
.
Fig
u
r
e
2
.
Mo
b
ile
P
ay
m
e
n
t M
o
d
el
I
n
m
o
b
ile
p
a
y
m
e
n
t
m
o
d
el
c
o
n
s
u
m
er
is
a
p
er
s
o
n
w
h
o
wan
ts
to
b
u
y
g
o
o
d
s
o
r
s
er
v
ice
s
f
r
o
m
t
h
e
m
er
ch
a
n
t
w
it
h
a
NFC
en
ab
led
m
o
b
ile
p
h
o
n
e.
A
m
er
c
h
a
n
t
is
an
en
tit
y
w
h
o
h
a
s
p
r
o
d
u
cts
o
r
s
er
v
ices
to
s
ell
w
it
h
a
NFC
r
ea
d
er
.
I
s
s
u
er
is
t
h
e
co
n
s
u
m
er
’
s
b
an
k
w
h
ich
i
n
ter
ac
ts
b
et
w
ee
n
th
e
p
a
y
m
e
n
t
s
er
v
er
a
n
d
th
e
co
n
s
u
m
er
.
A
cq
u
ir
er
is
t
h
e
m
er
ch
an
t
’
s
b
an
k
w
h
ic
h
i
n
ter
ac
ts
w
it
h
th
e
p
a
y
m
en
t
s
er
v
er
a
n
d
t
h
e
m
er
ch
a
n
t
’
s
P
OS.
T
h
e
p
ay
m
en
t
s
er
v
er
is
a
n
in
t
er
m
ed
iate
en
tit
y
b
et
w
ee
n
th
e
ac
q
u
ir
er
an
d
th
e
is
s
u
er
,
r
esp
o
n
s
ib
le
f
o
r
p
ay
m
e
n
t
au
th
o
r
izati
o
n
a
n
d
clea
r
in
g
.
T
h
e
f
r
a
u
d
d
etec
tio
n
a
n
d
p
r
ev
e
n
ti
o
n
en
tit
y
m
o
n
ito
r
s
tr
an
s
ac
tio
n
ac
tiv
i
ties
,
id
en
ti
f
y
an
d
v
er
i
f
y
w
h
et
h
er
a
tr
a
n
s
ac
ti
o
n
is
f
r
a
u
d
u
le
n
t o
r
le
g
iti
m
ate.
T
h
e
th
r
ea
ts
a
n
d
t
h
e
v
iab
le
co
u
n
ter
m
ea
s
u
r
e
s
o
f
t
h
e
m
o
b
ile
p
a
y
m
e
n
t
s
y
s
te
m
ar
e
d
e
s
cr
ib
ed
.
a.
Ma
l
w
ar
e
T
h
r
ea
t:
T
h
e
th
r
ea
t
s
ass
o
ciate
d
w
it
h
th
e
m
o
b
ile
d
e
v
ice
ar
e
m
al
w
ar
e
an
d
i
lleg
a
l
a
cc
ess
i
n
ca
s
e
o
f
lo
s
t/s
to
le
n
d
ev
ice.
Viab
le
co
u
n
ter
m
ea
s
u
r
es
ar
e
r
e
m
o
te
d
ata
w
ip
e,
m
u
lti
f
ac
to
r
au
t
h
en
ti
ca
tio
n
lik
e
P
I
N,
p
ass
w
o
r
d
,
b
io
m
etr
ic
etc.
,
OS
u
p
d
atio
n
ti
m
e
to
ti
m
e
a
n
d
a
n
ti
v
ir
u
s
.
b.
I
m
p
er
s
o
n
atio
n
T
h
r
ea
t:
T
h
e
t
h
r
ea
ts
b
et
w
ee
n
t
h
e
m
o
b
ile
d
ev
ice
an
d
P
OS
i
s
i
m
p
er
s
o
n
a
tio
n
an
d
r
ep
la
y
attac
k
.
T
h
e
p
o
s
s
ib
le
co
u
n
ter
m
ea
s
u
r
es a
r
e
E
n
cr
y
p
t
io
n
an
d
u
s
e
o
f
s
ec
u
r
e
p
r
o
to
co
ls
.
c.
R
ela
y
A
ttac
k
:
T
h
e
t
h
r
ea
ts
co
n
j
o
in
w
it
h
t
h
e
P
OS
a
r
e
m
al
w
ar
e
a
n
d
r
ela
y
at
ta
ck
.
T
h
e
v
iab
le
co
u
n
ter
m
ea
s
u
r
es a
r
e
s
o
f
t
w
ar
e
u
p
d
atio
n
,
f
ir
e
w
all
a
n
d
u
s
e
o
f
S
SL
/T
L
S c
o
n
n
ec
tio
n
.
d.
Data
L
ea
k
a
g
e
an
d
A
cc
e
s
s
C
o
n
tr
o
l:
T
h
e
th
r
ea
ts
ass
o
ciate
d
w
it
h
ac
q
u
ir
er
/is
s
u
er
ar
e
m
al
war
e,
d
ata
leak
ag
e,
d
ataset
h
ac
k
i
n
g
,
ac
ce
s
s
co
n
tr
o
l
an
d
p
a
y
m
e
n
t
f
r
au
d
.
T
h
e
v
iab
le
co
u
n
ter
m
ea
s
u
r
es
ar
e
m
u
lti
f
ac
to
r
au
th
e
n
tica
tio
n
f
o
r
ac
ce
s
s
,
f
r
au
d
p
r
ev
en
tio
n
s
tr
ateg
y
,
d
ata
at
r
est
en
cr
y
p
tio
n
an
d
u
s
e
o
f
SS
L
/T
L
S
co
n
n
ec
tio
n
.
e.
Data
Mo
d
if
icatio
n
:
T
h
e
th
r
e
ats
as
s
o
ciate
d
w
ith
p
a
y
m
en
t
s
er
v
ice
p
r
o
v
id
er
ar
e
d
ata
m
o
d
i
f
icat
io
n
a
n
d
r
ep
lay
.
T
h
e
v
iab
le
co
u
n
ter
m
ea
s
u
r
es a
r
e
u
s
e
o
f
s
ec
u
r
e
p
r
o
to
c
o
ls
an
d
en
cr
y
p
tio
n
.
T
h
e
m
o
b
ile
p
a
y
m
e
n
t
e
x
p
o
s
u
r
es
w
it
h
r
esp
ec
t
to
p
la
y
er
s
o
f
m
o
b
ile
p
a
y
m
e
n
t
s
y
s
te
m
a
n
d
ass
o
ciate
d
th
r
ea
t
s
alo
n
g
w
i
th
co
u
n
ter
m
ea
s
u
r
es a
r
e
b
esto
w
ed
to
ab
ate
th
e
s
ec
u
r
i
t
y
th
r
ea
t
s
.
5.
CO
NCLU
SI
O
N
T
h
e
co
m
f
o
r
t
to
p
ay
b
y
u
s
in
g
m
o
b
ile
d
ev
ice
is
co
n
v
e
n
ie
n
t
f
o
r
th
e
co
n
s
u
m
er
s
r
at
h
er
th
a
n
ca
r
r
y
i
n
g
th
eir
cr
ed
it/d
eb
it
ca
r
d
s
.
Ho
w
b
eit,
u
s
in
g
a
m
o
b
ile
d
ev
ice
f
o
r
p
er
f
o
r
m
in
g
f
i
n
an
c
ial
tr
an
s
ac
t
io
n
s
i
s
n
o
t
o
u
ts
id
e
f
o
r
tu
it
y
.
W
it
h
co
n
s
u
m
er
asp
ec
t
s
ec
u
r
it
y
,
f
ai
th
an
d
ac
c
e
s
s
ib
il
it
y
ar
e
th
e
p
iv
o
tal
e
le
m
e
n
t
s
i
n
m
o
b
ile
p
a
y
m
e
n
t
s
.
T
h
u
s
in
e
n
d
-
to
-
e
n
d
p
r
o
ce
s
s
o
f
m
o
b
ile
p
a
y
m
e
n
ts
,
b
e
g
in
n
i
n
g
f
r
o
m
tr
an
s
ac
tio
n
i
n
itia
tio
n
b
y
a
co
n
s
u
m
er
f
o
r
p
u
r
ch
ase,
au
t
h
e
n
ticatio
n
,
v
er
if
icatio
n
a
n
d
p
ay
m
e
n
t
s
u
cc
es
s
f
u
l/d
ec
li
n
ed
s
h
o
u
ld
g
u
ar
an
tee
a
s
ec
u
r
e
en
v
ir
o
n
m
e
n
t.
T
h
e
m
o
b
ile
p
a
y
m
en
t
ex
p
o
s
u
r
es
w
it
h
r
esp
ec
t
t
o
p
lay
er
s
o
f
m
o
b
ile
p
a
y
m
e
n
t
s
y
s
te
m
ar
e
d
is
c
u
s
s
ed
alo
n
g
w
it
h
t
h
e
ass
o
ciate
d
t
h
r
e
ats.
Viab
le
co
u
n
ter
m
ea
s
u
r
es a
r
e
b
esto
w
ed
th
at
w
i
ll h
e
lp
to
ab
ate
th
e
th
r
ea
t
s
.
ACK
NO
WL
E
D
G
E
M
E
NT
S
T
h
e
au
th
o
r
s
t
h
an
k
o
u
r
co
llea
g
u
e
s
f
r
o
m
K
L
E
Fo
u
n
d
atio
n
w
h
o
p
r
o
v
id
ed
d
is
ce
r
n
m
e
n
t
an
d
ass
i
s
ta
n
ce
th
at
co
n
s
p
icu
o
u
s
l
y
as
s
is
ted
t
h
e
r
es
ea
r
ch
ca
r
r
ied
b
y
u
s
.
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:
2
0
8
8
-
8708
Th
e
F
a
ct
-
F
in
d
in
g
S
ec
u
r
ity
E
xa
min
a
tio
n
in
N
F
C
-
en
a
b
led
M
o
b
ile
P
a
yme
n
t
…
(
P
in
ki
P
r
a
ka
s
h
V
is
h
w
a
ka
r
ma
)
1779
RE
F
E
R
E
NC
E
S
[1
]
W
.
Jia
n
p
in
g
,
“
T
h
e
A
n
a
l
y
sis
a
n
d
Op
ti
m
iza
ti
o
n
o
n
M
-
c
o
m
m
e
r
c
e
S
e
c
u
re
P
a
y
m
e
n
t
M
o
d
e
l,
”
2
0
1
1
T
h
ir
d
In
ter
n
a
ti
o
n
a
l
Co
n
fer
e
n
c
e
o
n
Co
mm
u
n
ica
t
io
n
s a
n
d
M
o
b
il
e
C
o
mp
u
t
in
g
,
Qi
n
g
d
a
o
,
2
0
1
1
,
p
p
.
4
1
-
4
4
.
[2
]
K.
S
.
Ka
d
a
m
b
i,
e
t
a
l.
,
“
Ne
a
r
-
f
i
e
ld
c
o
m
m
u
n
ica
ti
o
n
-
b
a
se
d
se
c
u
re
m
o
b
il
e
p
a
y
m
e
n
t
se
rv
ice
,
”
ICEC
'
0
9
T
a
ip
e
i
,
T
a
i
w
a
n
,
A
u
g
u
st 1
2
-
1
5
,
2
0
0
9
,
p
p
.
1
4
2
-
1
5
1
.
[3
]
Rich
a
rd
Ke
m
p
,
“
M
o
b
il
e
p
a
y
m
e
n
ts:
Cu
rre
n
t
a
n
d
e
m
e
rg
in
g
re
g
u
lat
o
ry
a
n
d
c
o
n
trac
ti
n
g
issu
e
s”
,
Co
mp
u
ter
L
a
w
&
S
e
c
u
rity R
e
v
iew
,
v
o
l.
2
9
,
n
o
.
2
,
A
p
ril
2
0
1
3
,
p
p
.
1
7
5
-
1
7
9
.
[4
]
S
.
K.
T
i
m
a
l
sin
a
,
e
t
a
l.
,
"
NFC
a
n
d
it
s
a
p
p
li
c
a
ti
o
n
to
m
o
b
il
e
p
a
y
m
e
n
t:
O
v
e
rv
i
e
w
a
n
d
c
o
m
p
a
ri
so
n
,
"
2
0
1
2
8
t
h
In
ter
n
a
t
io
n
a
l
Co
n
fer
e
n
c
e
o
n
In
f
o
rm
a
ti
o
n
S
c
ien
c
e
a
n
d
Dig
it
a
l
Co
n
ten
t
T
e
c
h
n
o
l
o
g
y
(
ICIDT2
0
1
2
)
,
Je
ju
,
2
0
1
2
,
p
p
.
2
0
3
-
2
0
6
.
[5
]
S
.
M
.
S
h
a
riati,
e
t
a
l
.
,
"
In
v
e
stig
a
ti
n
g
NFC
tec
h
n
o
l
o
g
y
f
ro
m
th
e
p
e
rsp
e
c
ti
v
e
o
f
se
c
u
rit
y
,
a
n
a
l
y
sis
o
f
a
tt
a
c
k
s
a
n
d
e
x
isti
n
g
risk
,
"
2
0
1
5
2
n
d
In
ter
n
a
ti
o
n
a
l
Co
n
fer
e
n
c
e
o
n
K
n
o
wled
g
e
-
Ba
se
d
E
n
g
i
n
e
e
rin
g
a
n
d
I
n
n
o
v
a
ti
o
n
(
KBE
I)
,
T
e
h
ra
n
,
2
0
1
5
,
p
p
.
1
0
8
3
-
1
0
8
7
.
[6
]
A
.
A
r
m
a
n
d
o
,
e
t
a
l.
,
"
T
ru
ste
d
h
o
st
-
b
a
se
d
c
a
rd
e
m
u
latio
n
,
"
2
0
1
5
I
n
ter
n
a
ti
o
n
a
l
Co
n
fer
e
n
c
e
o
n
Hig
h
Per
fo
rm
a
n
c
e
Co
mp
u
t
in
g
&
S
imu
la
ti
o
n
(
HPCS
)
,
Am
ste
rd
a
m
,
2
0
1
5
,
p
p
.
2
2
1
-
2
2
8
.
[7
]
D.
Ca
v
d
a
r
a
n
d
E.
T
o
m
u
r,
"
A
p
ra
c
ti
c
a
l
NFC
re
la
y
a
tt
a
c
k
o
n
m
o
b
il
e
d
e
v
ice
s
u
sin
g
c
a
rd
e
m
u
latio
n
m
o
d
e
,
"
2
0
1
5
3
8
t
h
In
ter
n
a
t
io
n
a
l
Co
n
v
e
n
ti
o
n
o
n
In
fo
rm
a
ti
o
n
a
n
d
Co
mm
u
n
ica
ti
o
n
T
e
c
h
n
o
l
o
g
y
,
El
e
c
tro
n
ics
a
n
d
M
icr
o
e
lec
tro
n
ics
(
M
IPR
O)
,
Op
a
ti
ja,
2
0
1
5
,
p
p
.
1
3
0
8
-
1
3
1
2
.
[8
]
M
ich
a
e
l
Ro
lan
d
a
n
d
Jo
se
f
Lan
g
e
r
,
"
Co
m
p
a
riso
n
o
f
th
e
u
sa
b
il
it
y
a
n
d
se
c
u
rit
y
o
f
NFC'
s
d
iff
e
re
n
t
o
p
e
ra
ti
n
g
m
o
d
e
s
in
m
o
b
il
e
d
e
v
ice
s,"
El
e
k
tro
tec
h
n
ik
u
n
d
I
n
fo
rm
a
t
io
n
ste
c
h
n
ik,
N
o
v
e
m
b
e
r
2
0
1
3
,
v
o
l.
1
3
0
,
n
o
.
7,
p
p
.
2
0
1
-
2
0
6
.
[
9
]
B
a
n
g
d
a
o
C
.
a
n
d
R
o
s
c
o
e
A
.
W
,
“
M
o
b
i
l
e
E
l
e
c
t
r
o
n
i
c
I
d
e
n
t
i
t
y
:
S
e
c
u
r
i
n
g
P
a
y
m
e
n
t
o
n
M
o
b
i
l
e
P
h
o
n
e
s
”
I
n
:
A
r
d
a
g
n
a
C
.
A
.
,
Z
h
o
u
J
.
(
e
d
s
)
I
n
f
o
r
m
a
t
i
o
n
S
e
c
u
r
i
t
y
T
h
e
o
r
y
a
n
d
P
r
a
c
t
i
c
e
.
S
e
c
u
r
i
t
y
a
n
d
P
r
i
v
a
c
y
o
f
M
o
b
i
l
e
D
e
v
i
c
e
s
i
n
W
i
r
e
l
e
s
s
C
o
m
m
u
n
i
c
a
t
i
o
n
.
W
I
S
T
P
2
0
1
1
.
L
e
c
t
u
r
e
N
o
t
e
s
i
n
C
o
m
p
u
t
e
r
S
c
i
e
n
c
e
,
v
o
l
u
m
e
6
6
3
3
.
S
p
r
i
n
g
e
r
,
B
e
r
l
i
n
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CS
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