I
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t
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na
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o
urna
l o
f
Adv
a
nces in Applie
d Science
s
(
I
J
AAS)
Vo
l.
5
,
No
.
2
,
J
u
n
e
201
6
,
p
p
.
94
~
10
0
I
SS
N:
2252
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8814
94
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206
7
In
s
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A
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1.
I
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UCT
I
O
N
T
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f
u
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d
a
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k
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to
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d
ca
lled
p
ass
w
o
r
d
au
t
h
e
n
ticatio
n
[
4
0
]
.
B
a
s
icall
y
w
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u
s
e
alp
h
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m
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ic
p
ass
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b
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m
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y
d
e
f
icie
n
cies
i
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it
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e
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p
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as
s
w
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r
d
s
w
h
ic
h
ar
e
s
h
o
r
t
[
4
1
]
.
Ma
n
y
p
eo
p
le
u
s
e
n
a
m
es,
p
h
o
n
e
n
o
.
o
r
an
y
o
th
er
ea
s
y
p
h
r
ase
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m
e
m
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er
,
b
u
t
t
h
e
y
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er
y
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ict
to
h
ac
k
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g
.
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n
o
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er
to
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p
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r
d
ata
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in
f
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ec
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w
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to
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o
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u
g
h
to
th
e
h
ac
k
er
s
f
o
r
g
u
es
s
i
n
g
[
4
2
]
,
[
4
3
]
.
W
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u
s
e
in
ter
n
e
t
f
o
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m
a
n
y
p
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r
p
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b
u
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g
a
s
m
al
l
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ec
t
to
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g
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j
ec
t
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ith
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t
i
n
ter
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co
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m
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ca
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s
u
r
v
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f
a
s
t
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er
n
w
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ld
o
f
d
ev
elo
p
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en
t.
T
o
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ay
ev
er
y
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n
d
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s
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d
t
h
e
y
m
a
y
u
s
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it
f
o
r
b
an
k
in
g
[
2
4
]
p
u
r
p
o
s
e
also
w
h
ic
h
r
eq
u
ir
es
a
h
ig
h
s
ec
u
r
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t
y
.
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n
o
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r
d
ail
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f
e
w
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u
s
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m
an
y
d
e
v
ices
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d
i
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et
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al
co
m
p
u
ter
s
,
s
o
cial
n
e
t
w
o
r
k
i
n
g
s
ites
,
E
-
m
ails
an
d
m
a
n
y
m
o
r
e.
Fo
r
ea
s
y
to
r
e
m
e
m
b
er
w
e
u
s
e
o
n
e
p
ass
w
o
r
d
to
all
o
u
r
ac
co
u
n
t
s
w
h
ic
h
r
ed
u
ce
s
s
ec
u
r
it
y
[
4
4
]
,
[
4
5
]
.
A
u
th
e
n
tica
tio
n
d
eter
m
i
n
es
w
h
et
h
er
u
s
er
i
s
v
alid
o
r
n
o
t
.
I
n
ad
v
a
n
ce
a
u
th
e
n
ticat
io
n
p
r
o
ce
s
s
g
r
ap
h
ical
p
as
s
w
o
r
d
s
[
1
]
p
lay
s
a
p
r
o
m
in
e
n
t
p
lace
to
s
ec
u
r
e
t
h
e
u
s
er
s
ac
co
u
n
t
i
n
f
o
r
m
atio
n
.
I
n
g
r
ap
h
ical
p
ass
w
o
r
d
m
et
h
o
d
s
it
h
as
d
if
f
er
en
t
w
a
y
s
lik
e
p
atter
n
m
et
h
o
d
[
6
]
,
w
h
ic
h
w
as
u
s
ed
i
n
o
u
r
m
o
b
ile
p
h
o
n
es
to
u
n
lo
c
k
it.
T
ex
t
b
as
ed
o
n
e
is
th
e
g
e
n
er
al
p
ass
w
o
r
d
w
h
ich
co
n
s
i
s
ts
o
f
n
a
m
e
s
,
n
u
m
b
er
s
o
r
an
y
o
t
h
e
r
p
h
r
ases
.
A
lp
h
an
u
m
er
ic
p
ass
w
o
r
d
co
n
s
i
s
ts
o
f
te
x
t
an
d
n
u
m
b
er
s
.
Gr
ap
h
ica
l
p
ass
w
o
r
d
[
7
]
co
n
s
is
ts
o
f
i
m
a
g
es
f
o
r
s
ec
u
r
it
y
,
i
n
w
h
ic
h
it
ca
n
u
s
e
f
o
r
p
ass
p
o
in
ts
,
h
o
t
s
p
o
ts
etc.
I
n
n
ex
t
lev
el
o
f
ad
v
an
ce
m
e
th
o
d
ca
p
tch
a
w
a
s
u
s
ed
,
in
w
h
ich
ca
p
tch
a
is
u
s
ed
to
d
is
tin
g
u
is
h
h
u
m
a
n
s
an
d
b
o
ts
ap
ar
t.
C
A
P
T
C
HA
[
2
8
]
is
ac
r
o
n
y
m
o
f
C
o
m
p
letel
y
Au
to
m
ated
P
u
b
lic
T
u
r
n
in
g
te
s
t
to
tell
C
o
m
p
u
ter
s
a
n
d
H
u
m
an
s
A
p
ar
t.
C
ap
tch
a
co
n
s
i
s
ts
o
f
te
x
t
an
d
n
u
m
b
er
s
i
n
d
i
f
f
e
r
e
n
t
f
o
n
t
s
t
y
les.
I
n
m
y
p
r
o
j
ec
t
w
e
h
av
e
u
s
ed
th
is
co
n
ce
p
t
f
o
r
s
ec
u
r
it
y
an
d
d
ev
elo
p
th
i
s
w
o
r
k
.
Evaluation Warning : The document was created with Spire.PDF for Python.
IJ
AA
S
I
SS
N:
2252
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8814
Gra
p
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p
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w
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s
,
alp
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ic
p
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w
o
r
d
s
,
g
r
ap
h
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p
ass
w
o
r
d
s
[
3
4
]
,
h
o
t
s
p
o
ts
o
n
i
m
ag
e
s
,
p
as
s
p
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in
t
s
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d
m
an
y
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t
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s
.
T
h
ese
t
y
p
e
s
w
er
e
ea
s
il
y
p
o
n
e
to
attac
k
s
.
T
h
er
e
ar
e
m
a
n
y
t
y
p
e
s
o
f
attac
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s
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a
m
e
l
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ar
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attac
k
s
,
r
ela
y
attac
k
s
,
s
h
o
u
ld
er
s
u
r
f
in
g
[
2
5
]
,
[
2
6
]
attac
k
s
,
b
r
u
tal
at
tack
s
etc.
1)
I
n
b
r
u
tal
f
o
r
ce
attac
k
o
n
l
y
s
m
all
le
n
g
th
p
as
s
w
o
r
d
s
ca
n
b
e
f
o
u
n
d
,
in
t
h
is
al
g
o
r
ith
m
it
s
ea
r
ch
es
all
t
h
e
p
o
s
s
ib
le
ele
m
e
n
ts
[
1
6
]
u
n
ti
l th
e
co
r
r
ec
t p
ass
w
o
r
d
f
o
u
n
d
.
I
t c
an
r
esis
t
s
to
li
m
ited
ch
ar
ac
ter
s
o
n
l
y
[
9
]
.
2)
I
n
d
ictio
n
ar
y
attac
k
it
i
n
v
o
l
v
es
g
u
e
s
s
i
n
g
p
ass
w
o
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d
s
f
r
o
m
lis
t
o
f
d
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n
ar
y
;
it
h
as
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p
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s
ib
ilit
y
o
f
g
u
e
s
s
i
n
g
w
h
e
n
it
w
a
s
in
a
lp
h
ab
etica
l
o
r
d
er
.
I
t
w
il
l
h
a
v
e
less
p
o
s
s
ib
ili
t
y
w
h
e
n
it
co
n
s
i
s
ts
o
f
d
i
f
f
er
en
t
ch
ar
ac
ter
s
in
p
as
s
w
o
r
d
.
I
t ta
k
es lo
n
g
t
i
m
e
f
o
r
s
ea
r
ch
i
n
g
ac
co
r
d
in
g
to
th
e
le
n
g
th
o
f
th
e
p
as
s
w
o
r
d
[
1
0
]
.
3)
I
n
s
h
o
u
ld
er
s
u
r
f
in
g
attac
k
i
t
r
ef
er
s
to
s
o
m
eo
n
e
u
s
i
n
g
d
ir
ec
t
o
b
s
er
v
atio
n
o
f
p
ass
w
o
r
d
b
y
o
th
er
m
ea
n
s
li
k
e
v
id
eo
r
ec
o
r
d
in
g
,
k
e
y
s
tr
o
k
e
[
1
5
]
r
ec
o
r
d
in
g
,
s
o
m
eo
n
e
w
atc
h
es
o
v
er
t
h
e
u
s
er
‟
s
s
h
o
u
ld
er
as
u
s
er
e
n
ter
s
a
p
ass
w
o
r
d
[
1
3
]
.
4)
P
h
is
h
i
n
g
[
1
1
]
is
w
a
y
in
w
h
ic
h
h
ac
k
er
ca
n
ac
q
u
ir
e
co
n
f
id
e
n
tial
in
f
o
r
m
at
io
n
l
ik
e
u
s
er
n
a
m
es,
p
a
s
s
w
o
r
d
s
;
cr
ed
it
in
f
o
r
m
at
io
n
‟
s
b
y
cr
ea
ti
n
g
a
n
id
en
tical
p
ag
e
li
k
e
u
s
er
ac
ce
s
s
s
ites
i.e
.
f
a
k
e
w
eb
s
ite
s
lo
o
k
lik
e
an
d
f
ee
ls
li
k
e
s
a
m
e
to
le
g
iti
m
ate
o
n
e
an
d
in
f
o
r
m
a
tio
n
i
s
ca
r
r
ied
o
u
t th
r
o
u
g
h
e
-
m
ail
s
p
o
o
f
in
g
.
5)
P
h
ar
m
in
g
[
1
2
]
is
ad
v
an
ce
d
v
e
r
s
io
n
o
f
p
h
i
s
h
i
n
g
in
w
h
ic
h
in
t
en
d
ed
to
r
ed
ir
ec
t
a
w
eb
s
ite
to
an
o
th
er
b
o
g
u
s
s
ite.
I
t c
r
ea
tes v
u
ln
er
ab
ilit
y
i
n
DNS
s
er
v
er
s
o
f
t
w
ar
e.
C
o
m
p
r
e
s
s
ed
DNS
s
er
v
er
s
ar
e
r
ef
er
r
ed
as p
o
is
o
n
ed
.
C
o
m
p
u
ter
s
u
s
ed
b
y
h
ac
k
er
s
i
n
s
talled
w
i
th
s
o
f
t
w
ar
e
in
w
h
ic
h
it
g
en
er
ates
r
an
d
o
m
l
y
f
r
o
m
s
e
q
u
en
ce
o
f
alp
h
ab
ets
a
n
d
f
i
n
all
y
w
e
ca
n
g
et
t
h
e
r
eq
u
ir
ed
o
n
e
at
a
n
y
p
o
in
t
o
f
ti
m
e
a
n
d
th
e
y
ca
n
u
s
e
it
,
it‟
s
j
u
s
t
li
k
e
to
k
e
n
g
en
er
atio
n
i
n
b
a
n
k
i
n
g
s
y
s
te
m
s
etc.
B
y
cl
ick
i
n
g
o
n
t
h
e
te
x
t
is
o
n
e
t
y
p
e
o
f
au
th
e
n
ticatio
n
ca
l
led
C
lic
k
-
T
ex
t
[
4
]
.
w
e
u
s
er
u
s
es
h
is
/
h
er
ac
co
u
n
t
in
p
u
b
lic
p
lace
s
h
ac
k
er
s
ca
n
g
et
it
b
y
k
e
y
lo
g
g
er
s
.
Ke
y
lo
g
g
er
s
ar
e
s
o
f
t
w
ar
e
in
w
h
ic
h
it
ca
n
r
ec
o
r
d
th
e
k
ey
s
p
r
ess
ed
b
y
th
e
u
s
er
at
th
e
ti
m
e
o
f
en
ter
in
g
u
s
er
n
a
m
e
a
n
d
p
ass
w
o
r
d
s
.
So
th
is
i
s
an
o
th
er
t
y
p
e
o
f
h
ac
k
i
n
g
tec
h
n
i
q
u
e.
Su
p
e
r
co
m
p
u
ter
s
ar
e
th
o
s
e
w
h
ic
h
f
a
s
t i
n
ac
tio
n
s
w
h
e
n
c
o
m
p
ar
ed
to
n
o
r
m
a
l
co
m
p
u
ter
s
.
T
h
e
y
ca
n
g
e
t
th
e
in
f
o
r
m
atio
n
w
h
ic
h
w
er
e
d
is
p
l
a
y
ed
o
n
th
e
s
cr
ee
n
[
3
]
an
d
c
an
d
ec
o
d
e
its
elf
i
n
o
r
d
er
t
o
f
ill
th
e
f
o
r
m
s
in
r
eg
i
s
tr
atio
n
o
f
t
h
e
u
s
er
au
th
e
n
tica
tio
n
an
d
m
a
n
y
o
t
h
er
w
a
y
s
.
T
h
ese
co
m
p
u
ter
s
ca
n
ea
s
il
y
g
r
ab
th
e
in
f
o
r
m
atio
n
w
h
ic
h
is
v
er
y
u
s
e
f
u
l
in
h
ac
k
in
g
.
I
n
r
ec
en
t
r
esear
ch
e
s
th
e
y
f
o
u
n
d
th
at
s
u
p
er
co
m
p
u
ter
s
ca
n
n
o
t
g
et
th
e
i
n
f
o
r
m
atio
n
w
h
ic
h
w
as o
n
th
e
i
m
a
g
es
.
3.
RE
L
AT
E
D
WO
RK
3
.
1
.
G
ra
ph
ia
l P
a
s
s
w
o
rd
I
n
g
r
ap
h
ical
p
ass
w
o
r
d
[
1
]
s
c
h
e
m
a
i
m
a
g
es
w
er
e
u
s
ed
as
p
ass
w
o
r
d
f
o
r
au
th
e
n
ticatio
n
,
im
ag
e
s
w
er
e
u
s
ed
in
d
if
f
er
e
n
t
tech
n
iq
u
e
s
f
o
r
au
th
e
n
ticat
io
n
lik
e
p
as
s
p
o
in
ts
[
1
7
]
,
[
1
8
]
,
h
o
t
s
p
o
t.
I
m
ag
es
w
er
e
u
s
ed
i
n
s
eq
u
en
ce
to
u
n
lo
ck
;
t
h
is
r
ec
o
r
d
s
th
e
p
atter
n
[
2
9
]
o
f
click
s
o
n
th
e
i
m
ag
e
s
.
P
ass
lo
g
i
x
[
8
]
ar
e
u
s
ed
to
ch
ec
k
u
s
er
click
s
.
R
ec
o
g
n
itio
n
–
b
ased
s
ch
e
m
e
r
eq
u
ir
es
id
en
t
if
y
i
n
g
a
m
o
n
g
d
ec
o
y
o
f
i
m
a
g
es.
Face
r
ec
o
g
n
itio
n
is
o
n
e
o
f
th
e
t
y
p
es
o
f
a
u
t
h
en
ticatio
n
r
ef
er
s
to
P
ass
f
ac
es.
I
n
t
h
i
s
it
s
to
r
es
t
h
e
i
m
a
g
es
o
f
t
h
e
f
ac
e
s
i
n
d
atab
ase
in
g
r
id
[
3
5
]
s
ec
tio
n
an
d
s
ec
tio
n
s
w
er
e
n
o
t
ed
f
o
r
v
er
if
icatio
n
a
n
d
w
h
en
i
t
m
atch
e
s
w
it
h
th
e
a
u
th
e
n
ticat
io
n
ti
m
e
it
ac
ce
p
t
s
an
d
r
est it r
ej
ec
ts
.
I
n
Dr
a
w
-
A
-
Secr
et
(
DAS)
[
3
1
]
u
s
er
r
ec
o
r
d
s
h
is
p
as
s
w
o
r
d
b
y
d
r
a
w
in
g
o
n
2
D
g
r
id
.
S
y
s
te
m
e
n
co
d
es th
e
s
eq
u
en
ce
o
f
g
r
id
ce
lls
alo
n
g
d
r
a
w
i
n
g
p
at
h
o
f
u
s
er
.
P
ass
-
Go
[
3
0
]
im
p
r
o
v
e
s
D
A
S
[
2
0
]
u
s
ab
ilit
y
b
y
i
n
ter
s
ec
ti
n
g
g
r
id
in
ter
s
ec
tio
n
p
o
in
t
r
ath
er
th
an
g
r
id
ce
lls
.
B
DAS
[
3
2
]
,
[
3
3
]
a
d
d
s
b
ac
k
g
r
o
u
n
d
i
m
a
g
es
to
DA
S
to
cr
ea
te
u
s
er
s
m
o
r
e
co
m
p
lex
p
ass
w
o
r
d
s
.
C
u
ed
-
r
ec
all
s
ch
e
m
e,
a
n
ex
ter
n
al
c
u
e
i
s
e
x
is
ts
to
m
e
m
o
r
ize
an
d
e
n
ter
s
p
ass
w
o
r
d
.
P
ass
P
o
in
ts
[
2
1
]
is
w
id
el
y
u
s
ed
click
-
b
ased
cu
ed
-
r
ec
all
s
c
h
e
m
e
w
h
er
e
click
s
w
er
e
r
ec
o
r
d
ed
an
d
h
av
e
r
e
-
clic
k
ed
s
a
m
e
d
u
r
i
n
g
a
u
th
e
n
tica
tio
n
.
C
u
ed
c
lick
p
o
in
t
(
C
C
P
)
[
3
6
]
is
s
i
m
i
lar
to
P
ass
P
o
in
t
b
u
t
u
s
ed
o
n
e
i
m
a
g
e
p
er
click
,
in
w
h
ich
n
ex
t
i
m
a
g
e
s
elec
t
s
b
y
f
u
n
ctio
n
.
P
er
s
u
asiv
e
C
u
ed
C
lic
k
P
o
in
t
(
P
C
C
P
)
[
5
]
is
ex
ten
d
i
n
g
C
C
P
b
y
s
e
lecti
n
g
a
p
o
in
t o
n
i
m
a
g
e
r
es
u
lti
n
g
i
n
cr
e
atin
g
r
an
d
o
m
clic
k
.
3
.
2
.
Ca
ptc
ha
C
ap
tch
a
i
s
g
e
n
er
all
y
u
s
ed
to
d
if
f
er
en
tia
te
h
u
m
an
s
a
n
d
b
o
ts
ap
ar
t.
I
t c
o
n
s
is
ts
o
f
te
x
t [
2
2
]
an
d
n
u
m
b
er
s
in
it
i
n
d
i
f
f
er
en
t
f
o
n
t
s
.
I
t
is
an
ac
r
o
n
y
m
o
f
C
o
m
p
letel
y
Au
to
m
ated
P
u
b
lic
T
u
r
n
i
n
g
test
to
t
ell
C
o
m
p
u
ter
s
a
n
d
Hu
m
an
s
A
p
ar
t.
T
w
o
t
y
p
es
o
f
v
is
u
al
C
ap
tch
a
ar
e
te
x
t
C
ap
t
ch
a
[
3
9
]
an
d
I
m
a
g
e
-
R
ec
o
g
n
i
t
io
n
C
ap
tc
h
a
(
I
R
C
)
[
2
3
]
.
I
n
itial
r
ec
o
g
n
itio
n
is
o
n
ch
ar
ac
ter
w
h
ile
r
est
is
o
n
n
o
n
-
c
h
ar
ac
ter
o
b
j
ec
ts
.
T
ex
t
C
a
p
tch
a
i
s
r
el
y
in
g
o
n
d
if
f
ic
u
lt
y
o
f
c
h
ar
ac
ter
s
e
g
m
e
n
tatio
n
,
w
h
ich
is
h
ar
d
an
d
e
x
p
e
n
s
i
v
e
co
m
p
u
tatio
n
all
y
.
I
R
C
s
r
el
y
o
n
d
i
f
f
ic
u
lt
y
o
f
o
b
j
ec
t
id
en
tif
icatio
n
o
r
class
i
f
icatio
n
.
Asi
r
r
a
[
3
8
]
r
elies
o
n
b
in
ar
y
o
b
j
ec
t
class
if
icatio
n
:
a
u
s
er
is
as
k
ed
to
id
en
ti
f
y
al
l
t
h
e
ca
ts
f
r
o
m
a
p
an
el
o
f
i
m
a
g
e
s
o
f
ca
t
s
an
d
d
o
g
s
[
1
9
]
.
C
ap
tch
a
ca
n
b
e
cir
cu
m
v
en
ted
th
r
o
u
g
h
r
ela
y
attac
k
s
w
h
er
eb
y
C
ap
tch
a
c
h
all
en
g
e
s
ar
e
r
ela
y
ed
to
h
u
m
a
n
s
o
lv
er
s
,
w
h
o
s
e
a
n
s
w
er
s
ar
e
f
ed
b
ac
k
to
t
h
e
tar
g
eted
ap
p
licatio
n
.
I
n
r
esear
c
h
es
m
a
d
e
o
n
h
u
m
an
s
it
w
as
n
o
ticed
th
at
h
u
m
a
n
s
r
ec
o
g
n
ize
i
m
a
g
e
s
lo
n
g
er
ti
m
e
w
h
e
n
co
m
p
ar
ed
to
p
h
r
ases
,
n
u
m
b
er
etc.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
2
5
2
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IJ
AA
S
Vo
l.
5
,
No
.
2
,
J
u
n
e
2
0
1
6
:
94
–
10
0
96
I
n
m
an
y
b
a
n
k
i
n
g
s
ites
in
o
r
d
er
to
r
eg
is
ter
a
u
s
er
C
A
P
T
C
HA‟
s
w
er
e
u
s
ed
i
n
o
r
d
er
to
av
o
id
b
o
ts
in
ter
f
er
e
n
ce
in
it
a
n
d
m
ak
e
i
t
p
er
f
ec
tl
y
b
y
h
u
m
an
s
.
C
A
P
T
C
HA‟
s
w
er
e
o
f
d
if
f
er
en
t
t
y
p
es
in
w
h
ic
h
s
m
all
eq
u
atio
n
w
a
s
g
i
v
e
n
an
d
a
n
s
wer
h
as
to
t
y
p
e
as
co
n
f
o
r
m
atio
n
,
eq
u
atio
n
w
as
i
n
i
m
a
g
e
to
av
o
id
b
o
ts
,
w
h
ic
h
ca
n
ea
s
il
y
s
o
lv
e
it
w
h
e
n
th
e
y
w
er
e
in
tex
t
f
o
r
m
at.
T
h
is
tec
h
n
iq
u
e
is
w
id
el
y
u
s
ed
to
av
o
id
b
o
ts
f
il
lin
g
t
h
e
f
o
r
m
s
.
Ma
n
y
o
r
g
a
n
izatio
n
s
to
s
ec
u
r
e
th
eir
in
f
o
r
m
atio
n
th
e
y
u
s
e
d
if
f
er
en
t
s
ec
u
r
it
y
tech
n
iq
u
es.
I
n
o
u
r
d
ail
y
lif
e
w
e
u
s
e
m
an
y
s
u
c
h
tec
h
n
iq
u
es
o
n
e
o
f
it
w
a
s
,
d
u
r
in
g
o
u
r
tr
a
n
s
ac
tio
n
s
in
b
an
k
in
g
t
h
r
o
u
g
h
n
et
b
an
k
i
n
g
a
f
ter
r
eg
i
s
ter
i
n
g
th
r
o
u
g
h
o
u
r
m
o
b
ile
p
h
o
n
e
w
e
g
et
aler
t b
y
w
h
ich
w
e
ca
n
ac
k
n
o
w
led
g
e
w
h
at
h
a
s
f
r
o
m
o
u
r
ac
co
u
n
t a
t t
h
at
ti
m
e.
OT
P
is
also
o
n
e
o
f
th
e
s
ec
u
r
ed
p
r
o
ce
s
s
es,
w
h
ic
h
is
an
o
t
h
er
ad
v
a
n
ce
d
s
tep
in
s
ec
u
r
i
t
y
en
h
an
cin
g
.
I
n
th
is
u
s
er
g
e
ts
a
o
n
e
ti
m
e
p
ass
w
o
r
d
at
th
e
ti
m
e
o
f
tr
an
s
ac
tio
n
an
d
b
y
en
ter
i
n
g
th
e
n
u
m
b
er
w
h
ic
h
w
as
g
e
n
er
ated
an
d
s
en
t
to
th
e
m
o
b
ile
at
th
e
r
eq
u
ir
ed
ar
ea
w
e
ca
n
co
n
ti
n
u
e
o
u
r
tr
an
s
ac
tio
n
s
a
f
el
y
.
I
n
C
APT
C
HA
tec
h
n
iq
u
e
f
o
r
v
i
s
u
al
p
r
o
b
lem
s
p
er
s
o
n
au
d
io
f
ac
il
it
y
w
as
p
r
o
v
id
ed
.
As
m
en
tio
n
ed
ab
o
v
e
C
A
P
T
C
H
A
i
m
a
g
es
w
er
e
r
esis
ta
n
t to
Op
tical
C
h
ar
ac
ter
R
ec
o
g
n
itio
n
(
O
C
R
)
attac
k
s
.
I
n
n
e
w
m
e
th
o
d
o
f
C
A
P
T
C
H
A
u
s
er
d
o
es n
o
t r
eq
u
ir
e
to
en
ter
tex
t,
i
n
s
tead
u
s
er
w
er
e
ask
ed
to
s
elec
t
p
ic
k
o
r
i
m
ag
e
s
f
r
o
m
a
d
ec
o
y
o
f
i
m
a
g
e
s
.
T
h
is
ca
n
b
e
u
s
ed
a
s
g
r
ap
h
ical
p
ass
w
o
r
d
.
W
e
h
av
e
m
an
y
t
y
p
e
s
o
f
g
r
ap
h
ica
l
p
ass
w
o
r
d
in
d
e
m
a
n
d
.
I
n
w
8
an
i
m
ag
e
is
u
s
ed
in
w
h
ich
u
s
er
h
a
s
to
s
elec
t
f
e
w
p
o
in
t
i
n
s
eq
u
en
ce
i
n
o
r
d
er
to
ac
ce
s
s
n
ex
t
w
h
e
n
h
e/s
h
e
w
an
t
to
lo
g
i
n
.
W
h
en
lo
g
i
n
h
e
h
as
r
e
m
e
m
b
er
t
h
e
p
o
s
itio
n
s
at
w
h
ich
h
e
m
ad
e
p
o
in
ts
i
n
s
eq
u
e
n
ce
an
d
it
ac
t
s
as
a
p
ass
w
o
r
d
,
it‟
s
is
v
er
y
h
ar
d
to
r
e
m
e
m
b
er
s
o
it is
n
o
t u
s
ed
m
o
s
tl
y
.
3
.
3
.
Ca
ptc
ha
in Aut
hentic
a
t
io
n
I
n
th
is
p
r
o
to
co
l
C
ap
tch
a
an
d
p
ass
w
o
r
d
ar
e
u
s
ed
in
a
u
s
er
au
th
e
n
tica
tio
n
p
r
o
to
c
o
l,
w
h
ich
is
ca
lled
as
C
ap
tch
a
-
b
ased
P
ass
w
o
r
d
Au
th
en
ticatio
n
(
C
b
p
A
)
[
2
]
p
r
o
t
o
co
l
to
s
to
p
o
n
lin
e
d
ictio
n
a
r
y
at
tack
s
.
C
b
P
A
-
p
r
o
to
co
l
r
eq
u
ir
es
s
o
lv
in
g
a
C
ap
tch
a
ch
alle
n
g
e
v
alid
ati
n
g
u
s
er
I
D
an
d
p
ass
w
o
r
d
;
u
s
er
h
a
s
to
s
o
lv
e
C
ap
tch
a
ch
alle
n
g
e
b
e
f
o
r
e
d
en
ied
ac
ce
s
s
.
I
n
I
m
p
r
o
v
ed
C
b
P
A
-
p
r
o
to
co
l
[
2
]
o
n
ly
u
s
er
tr
u
s
ted
co
o
k
i
es
w
er
e
s
to
r
ed
an
d
ap
p
lied
C
ap
tch
a
ch
alle
n
g
e
o
n
l
y
o
n
n
u
m
b
er
o
f
f
ai
led
lo
g
in
a
t
te
m
p
ts
.
I
n
t
h
i
s
s
c
h
e
m
e
C
ap
tch
a
is
an
i
n
d
ep
en
d
en
t
en
tit
y
w
i
th
te
x
t
o
r
g
r
ap
h
ical
p
ass
w
o
r
d
ico
n
s
[
2
7
]
,
b
u
t
is
b
o
th
C
ap
tch
a
an
d
a
g
r
ap
h
ical
p
as
s
w
o
r
d
s
ch
e
m
e
[
1
4
]
w
h
ic
h
is
co
m
b
i
n
ed
in
to
a
s
i
n
g
l
e
en
tit
y
.
4.
P
RO
P
O
SE
D
WO
RK
I
n
th
i
s
p
ap
er
,
w
e
h
a
v
e
ad
d
ed
an
ex
tr
a
a
u
t
h
en
t
icatio
n
m
et
h
o
d
to
d
is
tin
g
u
i
s
h
b
o
ts
a
n
d
h
u
m
an
s
as
w
ell
as
to
a
v
o
id
s
u
p
er
co
m
p
u
ter
s
t
o
h
ac
k
b
y
u
s
i
n
g
i
m
a
g
es
(
ca
p
t
ch
a
)
as
o
n
e
o
f
th
e
p
ass
w
o
r
d
.
T
h
is
is
an
e
x
ten
s
io
n
m
ad
e
to
g
e
n
er
al
r
eg
i
s
tr
atio
n
p
r
o
ce
s
s
in
o
r
d
er
to
p
r
o
v
id
e
s
ec
u
r
it
y
.
I
m
a
g
e
a
u
t
h
en
t
ica
tio
n
d
is
c
u
s
s
u
n
d
er
g
r
ap
h
ical
p
a
s
s
w
o
r
d
s
,
it
h
a
s
b
ee
n
ta
k
e
n
i
n
to
co
n
s
id
er
t
h
at
c
ap
tch
a
i
n
a
n
i
m
a
g
e
f
o
r
m
a
t
a
n
d
m
ad
e
it
as
o
n
e
o
f
au
th
e
n
tica
tio
n
.
Fig
u
r
e
1
.
Flo
w
c
h
ar
t o
f
P
r
o
p
o
s
al
Evaluation Warning : The document was created with Spire.PDF for Python.
IJ
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Gra
p
h
ica
l P
a
s
s
w
o
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Usi
n
g
C
a
p
tch
a
(
Y.
C
h
a
n
d
r
a
S
ek
h
a
r
R
e
d
d
y
)
97
I
n
th
i
s
p
r
o
j
ec
t
w
e
h
a
v
e
u
s
ed
Net
b
ea
n
s
f
o
r
d
ev
elo
p
m
e
n
t
p
u
r
p
o
s
e,
j
s
p
‟
s
f
o
r
v
alid
atio
n
o
f
i
n
f
o
r
m
atio
n
en
ter
ed
in
t
h
e
p
ag
e,
f
r
o
n
te
n
d
u
s
i
n
g
HT
ML
an
d
b
ac
k
en
d
u
s
in
g
J
SP
.
I
n
lo
g
in
p
a
g
e
it
co
n
t
ain
s
o
f
o
n
e
Alp
h
a
-
n
u
m
er
ic
p
as
s
w
o
r
d
an
d
t
h
e
n
h
e/sh
e
h
a
s
to
s
e
lect
o
n
e
o
f
th
e
i
m
ag
e
s
(
ca
p
tch
a)
a
s
s
ec
o
n
d
p
as
s
w
o
r
d
w
h
ic
h
h
e/s
h
e
s
elec
ts
at
th
e
r
eg
i
s
tr
atio
n
ti
m
e
.
I
n
r
eg
is
tr
atio
n
p
ag
e
alo
n
g
w
ith
n
o
r
m
a
l
Alp
h
a
-
n
u
m
er
ic
p
ass
w
o
r
d
,
u
s
er
h
a
s
to
s
elec
t
a
n
i
m
ag
e
(
ca
p
tch
a)
as
s
ec
o
n
d
p
ass
w
o
r
d
an
d
h
e
/s
h
e
h
a
s
to
r
e
m
e
m
b
er
t
h
e
w
o
r
d
s
an
d
also
its
s
t
y
le
s
o
th
at
h
e
ca
n
lo
g
i
n
v
er
y
s
ec
u
r
el
y
w
it
h
o
u
t
f
ea
r
o
f
h
ac
k
in
g
.
W
h
e
n
u
s
er
w
a
n
ts
to
lo
g
in
h
e/
s
h
e
en
ter
s
is
A
lp
h
a
-
n
u
m
er
ic
p
ass
w
o
r
d
a
n
d
also
h
e/s
h
e
h
as
to
s
elec
t
h
is
i
m
a
g
e
w
h
ic
h
w
a
s
s
elec
ted
at
t
h
e
ti
m
e
o
f
r
eg
is
tr
a
tio
n
f
r
o
m
d
ec
o
y
o
f
i
m
a
g
es
[
3
7
]
an
d
also
o
f
d
if
f
er
en
t
f
o
n
t
s
t
y
le
s
o
f
s
a
m
e
w
o
r
d
,
ex
ac
t
i
m
ag
e
h
as
to
s
elec
t
f
r
o
m
it
an
d
h
e/s
h
e
ca
n
lo
g
in
s
u
cc
e
s
s
f
u
ll
y
,
i
f
n
o
t
h
e/s
h
e
r
ec
eiv
es
a
n
er
r
o
r
.
Fo
r
m
o
r
e
s
ec
u
r
it
y
r
ea
s
o
n
s
n
u
m
b
er
o
f
t
r
ails
w
ill
b
e
li
m
ited
an
d
af
ter
it a
cc
o
u
n
t
w
i
ll b
e
lo
c
k
ed
.
5.
RE
SU
L
T
S
A
ND
AN
AL
Y
SI
S
5
.
1
.
Reg
is
t
ra
t
io
n P
a
g
e
I
n
th
is
p
ag
e
g
en
er
al
d
etails
li
k
e
h
is
n
a
m
e
,
e
m
ail
r
eq
u
ir
ed
f
o
r
f
u
r
th
er
ass
i
s
ta
n
ce
,
u
s
er
n
a
m
e
w
h
ic
h
is
u
s
ed
d
u
r
i
n
g
lo
g
i
n
ti
m
e
a
n
d
p
a
s
s
w
o
r
d
o
f
alp
h
a
-
n
u
m
er
ic
a
n
d
t
h
en
s
u
b
m
it
d
etails
to
t
h
e
s
er
v
e
r
th
en
it
r
ed
ir
ec
t
to
ca
p
tch
a
s
elec
t
io
n
p
ag
e
in
w
h
i
ch
ca
p
tch
a
h
a
s
to
s
elec
t
f
r
o
m
d
ec
o
y
o
f
i
m
a
g
es,
b
u
t
i
n
t
h
is
w
e
m
e
n
tio
n
ed
o
n
l
y
f
e
w
f
o
r
ea
s
y
ap
p
ea
r
an
ce
.
Fig
u
r
e
2
.
R
eg
is
tr
at
io
n
P
ag
e
5
.
2
.
Ca
ptc
ha
Select
io
n
a
t
Reg
is
t
r
a
t
io
n
T
i
m
e
I
n
th
i
s
p
ag
e
u
s
er
n
ee
d
to
s
elec
t
h
is
ca
p
tc
h
a
f
o
r
f
u
tu
r
e
ac
ce
s
s
to
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I
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8814
IJ
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IJ
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8814
Gra
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ra
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.
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ru
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:
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(
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.
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.
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,
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.
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.
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.
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.
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.
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P
a
ss
wo
rd
S
c
h
e
me
”
,
In
six
th
In
tern
a
ti
o
n
a
l
C
o
n
f
e
re
n
c
e
o
n
Im
a
g
e
a
n
d
G
ra
p
h
ics
(ICIG
).
2
0
1
1
:
9
4
9
-
9
5
6
.
[1
5
]
X
.
L
iu
,
H.
GA
O,
L
.
W
a
n
g
a
n
d
X
.
Ch
a
n
g
,
“
A
n
En
h
a
n
c
e
d
Dra
w
i
n
g
Re
p
ro
d
u
c
ti
o
n
G
ra
p
h
ica
l
P
a
ss
w
o
rd
S
trate
g
y
”
.
Jo
u
rn
a
l
o
f
Co
m
p
u
ter S
c
ien
c
e
a
n
d
T
e
c
h
n
o
lo
g
y
.
2011
:
2
6
(6
):
9
8
8
-
9
9
9
.
[1
6
]
El
u
a
rd
,
M
.
;
M
a
e
tz,
Y.;
A
les
sio
,
D.;
“
Actio
n
-
b
a
se
d
g
ra
p
h
ica
l
p
a
ss
wo
rd
:
Cli
c
k
-
a
-
S
e
c
re
t
”
,
2
0
1
1
IEE
E
In
tern
a
ti
o
n
a
l
Co
n
f
e
re
n
c
e
o
n
Co
n
su
m
e
r
El
e
c
tro
n
ics
.
2
0
1
1
:
2
6
5
-
2
6
6
.
[1
7
]
H.C.
G
a
o
,
L
.
C.
M
a
,
J.H.Qiu
a
n
d
X
.
Y.L
iu
,
“
Exp
lo
r
a
ti
o
n
o
f
a
Ha
n
d
-
b
a
se
d
Gr
a
p
h
ica
l
Pa
ss
wo
rd
S
c
h
e
me
”
,
P
r
o
c
e
e
d
in
g
s o
f
th
e
4
th
in
tern
a
t
io
n
a
l
c
o
n
f
e
re
n
c
e
o
n
S
e
c
u
r
it
y
o
f
in
f
o
rm
a
ti
o
n
a
n
d
n
e
tw
o
rk
s
.
2
0
1
1
.
[1
8
]
P
.
C.
v
a
n
Oo
rsc
h
o
t
a
n
d
J.
T
h
o
rp
e
,
“
Ex
p
lo
it
i
n
g
p
re
d
icta
b
il
it
y
in
c
li
c
k
b
a
se
d
g
r
a
p
h
ica
l
p
a
ss
w
o
rd
s,”
J.
Co
m
p
u
t.
S
e
c
u
rit
y
,
v
o
l.
1
9
,
n
o
.
4
,
p
p
.
6
6
9
–
7
0
2
,
2
0
1
1
.
[1
9
]
R.
L
in
,
S
.
-
Y.
Hu
a
n
g
,
G
.
B.
Be
ll
,
a
n
d
Y.
-
K.
L
e
e
,
“
A
n
e
w
CAP
T
CHA
in
ter
fa
c
e
d
e
sig
n
fo
r
m
o
b
il
e
d
e
v
ice
s
,
”
in
P
r
o
c
.
1
2
t
h
A
u
stra
l.
Us
e
r
In
ter.
C
o
n
f
e
re
n
c
e
.
2
0
1
1
:
3
–
8.
[2
0
]
H.C.
G
a
o
.
,
Z.
J.
Re
n
.
,
X
.
L
.
C
h
a
n
g
.
,
X
.
Y.
L
iu
.
,
e
tc.
,
“
A
Ne
w
Gr
a
p
h
ica
l
P
a
ss
wo
rd
S
c
h
e
me
Res
ista
n
t
t
o
S
h
o
u
l
d
e
r
-
S
u
rfi
n
g
”
,
I
n
tern
a
ti
o
n
a
l
C
o
n
f
e
re
n
c
e
o
n
Cy
b
e
rw
o
rld
s (CW
).
De
c
e
m
b
e
r
2
0
1
0
:
1
9
4
-
1
9
9
.
[2
1
]
P
.
C.
v
a
n
Oo
rsc
h
o
t
,
A
.
S
a
leh
i
-
A
b
a
ri
a
n
d
J.
T
h
o
rp
e
.
“
P
u
re
ly
Au
to
m
a
ted
A
tt
a
c
k
s
o
n
P
a
ss
P
o
i
n
ts
-
S
ty
le
G
r
a
p
h
ica
l
P
a
ss
w
o
rd
s”
.
IEE
E
T
ra
n
s
a
c
ti
o
n
s o
n
In
f
o
rm
a
ti
o
n
Fo
re
n
sic
s
a
n
d
S
e
c
u
rity
.
2
0
1
0
:
5
(
3
):
3
9
3
-
4
0
5
.
[2
2
]
Z.
Zh
e
n
g
,
X
.
L
iu
,
L
.
Yin
,
Z.
L
iu
“
A
H
y
b
rid
p
a
ss
w
o
rd
a
u
th
e
n
ti
c
a
ti
o
n
sc
h
e
m
e
b
a
se
d
o
n
sh
a
p
e
a
n
d
te
x
t”,
Jo
u
rn
a
l
o
f
Co
m
p
u
ters
.
2
0
1
0
:
5
(
5
).
[2
3
]
B.
B.
Z
h
u
e
t
a
l
.
,
“
A
tt
a
c
k
s an
d
d
e
sig
n
o
f
im
a
g
e
re
c
o
g
n
it
io
n
CA
P
T
CH
As
,
”
in
P
ro
c
.
A
CM
CCS
.
2
0
1
0
:
187
–
2
0
0
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
2
5
2
-
8814
IJ
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S
Vo
l.
5
,
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.
2
,
J
u
n
e
2
0
1
6
:
94
–
10
0
100
[2
4
]
S
.
L
i,
S
.
A
.
H.
S
h
a
h
,
M
.
A
.
U.
Kh
a
n
,
S
.
A
.
Kh
a
y
a
m
,
A
.
-
R.
S
a
d
e
g
h
i,
a
n
d
R
.
S
c
h
m
it
z
,
“
Bre
a
k
in
g
e
-
b
a
n
k
in
g
CA
P
T
C
H
A
s,” in
P
r
o
c
.
A
CS
A
C,
2
0
1
0
:
1
–
1
0
.
[2
5
]
A
H
L
a
sh
k
a
ri,
e
t
a
l.
,
“
S
h
o
u
l
d
e
r
S
u
rf
in
g
a
tt
a
c
k
in
g
ra
p
h
ica
l
p
a
ss
w
o
rd
a
u
th
e
n
ti
c
a
ti
o
n
”
,
In
tern
a
ti
o
n
a
l
Jo
u
r
n
a
l
o
f
Co
m
p
u
ter S
c
ien
c
e
a
n
d
I
n
f
o
rm
a
ti
o
n
S
e
c
u
rit
y
(IJCSIS
).
2
0
0
9
:
6
(
2
)
.
[2
6
]
H.C.
GA
O,
X
.
Y.
L
iu
,
R.
Y.
Da
i,
e
tc.,
“
An
a
lys
is
a
n
d
Eva
l
u
a
ti
o
n
o
f
th
e
Co
lo
rL
o
g
in
Gr
a
p
h
ic
a
l
Pa
ss
wo
rd
S
c
h
e
me
”
.
T
h
e
5
th
I
n
tern
a
ti
o
n
a
l
C
o
n
f
e
r
e
n
c
e
o
n
Im
a
g
e
a
n
d
G
ra
p
h
ics
,
S
e
p
tem
b
e
r
2
0
0
9
:
2
0
-
2
3
.
[2
7
]
K.
Bica
k
c
i,
N.
B.
A
tala
y
,
M
.
Yu
c
e
e
l,
H.
G
u
rb
a
sla
r,
a
n
d
B.
Erd
e
n
iz,
“
T
o
wa
r
d
s
u
sa
b
l
e
so
lu
ti
o
n
s
to
g
ra
p
h
ica
l
p
a
ss
wo
rd
h
o
tsp
o
t
p
ro
b
lem
”
,
In
3
3
rd
A
n
n
u
a
l
IEE
E
In
ter
n
a
ti
o
n
a
l
C
o
m
p
u
ter
S
o
f
tw
a
re
a
n
d
A
p
p
li
c
a
ti
o
n
s
Co
n
f
e
re
n
c
e
.
2
0
0
9
.
[2
8
]
H.C.
G
a
o
,
X
.
Y.L
iu
,
S
.
D.W
a
n
g
,
R.
Y.Da
i.
“
A
n
e
w
g
ra
p
h
ic
a
l
p
a
ss
wo
rd
sc
h
e
me
a
g
a
i
n
st
sp
y
wa
re
b
y
u
sin
g
CAP
T
CHA
”
.
In
:
P
r
o
c
e
e
d
i
n
g
s o
f
th
e
sy
m
p
o
siu
m
o
n
u
sa
b
le p
riv
a
c
y
a
n
d
se
c
u
rit
y
.
Ju
ly
2009
:
15
-
1
7
.
[2
9
]
S
.
Ch
ias
so
n
,
A
.
F
o
rg
e
t,
E.
S
to
b
e
r
t,
P
.
C.
v
a
n
Ors
c
h
o
t
,
a
n
d
R.
Bi
d
d
le.
“
M
u
lt
ip
le
p
a
ss
w
o
rd
in
terf
e
re
n
c
e
in
tex
t
a
n
d
c
li
c
k
b
a
se
d
g
ra
p
h
ica
l
p
a
ss
w
o
rd
s”
.
In
A
CM
Co
m
p
u
ter an
d
C
o
m
m
u
n
ica
ti
o
n
s S
e
c
u
r
it
y
.
2
0
0
9
.
[3
0
]
H.
T
a
o
a
n
d
C.
A
d
a
m
s.
“
P
a
ss
-
Go
:
A
p
ro
p
o
sa
l
to
im
p
ro
v
e
th
e
u
sa
b
il
it
y
o
f
g
r
a
p
h
ica
l
p
a
ss
w
o
rd
s”
.
In
tern
a
ti
o
n
a
l
Jo
u
rn
a
l
o
f
Ne
tw
o
rk
S
e
c
u
rit
y
.
2
0
0
8
:
7
(
2
):
2
7
3
-
2
9
2
.
[3
1
]
P
.
C.
v
a
n
Oo
rsc
h
o
t
a
n
d
J.
T
h
o
rp
e
.
“
On
p
re
d
ictiv
e
m
o
d
e
ls
a
n
d
u
se
r
-
d
ra
w
n
g
ra
p
h
ica
l
p
a
ss
w
o
rd
s”
.
A
C
M
T
ra
n
sa
c
ti
o
n
s
on
I
n
f
o
rm
a
ti
o
n
a
n
d
S
y
ste
m
S
e
c
u
rit
y
.
2
0
0
8
:
1
0
(4
):
1
-
33.
[3
2
]
L
.
Y.
P
o
r,
X
.
T
.
L
im
,
M
.
T
.
S
u
,
a
n
d
F
.
Kia
n
o
u
sh
.
“
T
h
e
d
e
sig
n
a
n
d
im
p
le
m
e
n
tatio
n
o
f
b
a
c
k
g
ro
u
n
d
P
a
ss
-
G
o
sc
h
e
m
e
to
w
a
rd
s
se
c
u
rit
y
th
re
a
ts”
.
W
S
E
AS
T
ra
n
sa
c
ti
o
n
s
o
n
In
f
o
rm
a
ti
o
n
S
c
ien
c
e
a
n
d
A
p
p
li
c
a
ti
o
n
s.
Ju
n
e
2
0
0
8
:
5
(
6
):
9
4
3
-
9
5
2
.
[3
3
]
L
.
Y.
P
o
r
a
n
d
X.
T
.
L
im
,
“
M
u
lt
i
-
G
rid
b
a
c
k
g
ro
u
n
d
P
a
ss
-
G
o
”
.
W
S
EA
S
T
ra
n
sa
c
ti
o
n
s
o
n
In
f
o
r
m
a
ti
o
n
S
c
ien
c
e
a
n
d
A
p
p
li
c
a
ti
o
n
s.
7(
5
)
[3
4
]
H.
Ga
o
,
X
.
G
u
o
,
X.
Ch
e
n
,
L
.
Wan
g
,
a
n
d
X
.
L
iu
,
“
Y
AGP:
Y
e
t
a
n
o
th
e
r
g
ra
p
h
ic
a
l
p
a
ss
w
o
rd
stra
te
g
y
”
.
In
A
n
n
u
a
l
Co
m
p
u
ter S
e
c
u
rit
y
A
p
p
li
c
a
ti
o
n
s
Co
n
f
e
re
n
c
e
.
2
0
0
8
:
1
2
1
-
1
2
9
.
[3
5
]
R.
W
e
iss
a
n
d
A
.
De
L
u
c
a
,
“
P
a
ss
S
h
a
p
e
s
-
u
ti
li
z
in
g
str
o
k
e
b
a
se
d
a
u
t
h
e
n
ti
c
a
ti
o
n
t
o
i
n
c
re
a
se
p
a
ss
w
o
rd
m
e
m
o
ra
b
il
it
y
”
.
In
No
r
d
iCHI.
Oc
to
b
e
r
2
0
0
8
:
3
8
3
-
3
9
2
.
A
CM
.
[3
6
]
S
.
Ch
ias
so
n
,
A
.
F
o
rg
e
t,
R.
Bid
d
le,
a
n
d
P
.
C.
v
a
n
Oo
rsc
h
o
t.
“
In
f
lu
e
n
c
in
g
u
se
rs t
o
wa
rd
s b
e
tt
e
r
p
a
ss
wo
rd
s:
P
e
rsu
a
siv
e
Cu
e
d
Cli
c
k
-
P
o
i
n
ts”
.
I
n
Hu
m
a
n
Co
m
p
u
ter In
tera
c
ti
o
n
(HCI),
t
h
e
Br
it
ish
C
o
m
p
u
ter S
o
c
iety
.
S
e
p
tem
b
e
r
2
0
0
8
.
[3
7
]
E.
Ha
y
a
sh
i,
N.
C
h
risti
n
,
R.
Dh
a
m
ij
a
,
a
n
d
A
.
P
e
rrig
.
,
“
Us
e
Y
o
u
r
I
ll
u
sio
n
:
S
e
c
u
re
a
u
th
e
n
ti
c
a
ti
o
n
u
s
a
b
le
a
n
y
wh
e
re
”
,
In
4
t
h
A
CM
S
y
m
p
o
siu
m
o
n
Us
a
b
le P
r
iv
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.
[3
8
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.
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o
ll
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,
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.
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4
2
.
[3
9
]
J.
Ya
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.
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.
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.
[4
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a
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:
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.
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ly
M
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d
ia.
[4
1
]
A
.
A
d
a
m
s
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d
M
.
A
.
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a
ss
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.
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U
se
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ter
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h
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s
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w
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s”
.
Co
m
m
u
n
ica
ti
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s o
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A
CM
.
199
9:
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2
:
41
-
4
6
.
[4
2
]
D.
F
e
ld
m
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ier an
d
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.
Ka
rn
.
“
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w
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g
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st 1
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8
9
.
[4
3
]
R.
M
o
rris
a
n
d
K.
T
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so
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.
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ss
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Ca
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”
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M
.
1
9
7
9
:
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2
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1
)
:
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5
9
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.
[4
4
]
D.
F
lo
re
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c
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d
C.
He
rley
.
“
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l
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rg
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.
In
1
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t
h
A
CM
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tern
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ti
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rl
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id
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Co
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f
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re
n
c
e
(
W
WW
).
M
a
y
2
0
0
7
.
[4
5
]
A
d
a
m
s,
M
.
A
.
S
a
ss
e
,
a
n
d
P
.
L
u
n
t.
“
M
a
k
in
g
p
a
ss
wo
r
d
s
se
c
u
re
a
n
d
u
sa
b
le
”
.
In
HCI
9
7
:
P
ro
c
e
e
d
i
n
g
s
o
f
HCI
o
n
P
e
o
p
le an
d
C
o
m
p
u
ters
,
L
o
n
d
o
n
,
UK
,
1
9
9
7
:
1
-
19
.
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