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1
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Gar
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[
2
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d
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r
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r
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5
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d
ay
o
p
er
atio
n
s
.
I
n
d
u
s
tr
y
p
r
o
ce
s
s
es
an
d
s
y
s
tem
s
will
b
e
b
etter
co
n
tr
o
lled
an
d
m
o
n
ito
r
ed
,
in
cr
ea
s
in
g
o
v
er
all
s
af
ety
.
Qu
ality
o
f
life
will
al
s
o
r
is
e
as
a
r
esu
lt
o
f
th
e
tim
e,
m
o
n
ey
,
an
d
en
er
g
y
s
av
in
g
s
ass
o
ciate
d
with
th
ese
im
p
r
o
v
em
en
ts
.
New
s
er
v
ices
m
ay
also
b
e
d
ev
elo
p
e
d
in
th
e
r
esu
ltin
g
d
ata
-
r
ich
en
v
ir
o
n
m
e
n
t,
en
h
an
cin
g
h
u
m
an
well
-
b
ei
n
g
[
5
]
.
A
b
u
s
in
ess
th
at
ad
o
p
ts
I
o
T
c
an
ex
p
ec
t
im
p
r
o
v
ed
s
ec
u
r
ity
,
ef
f
icien
cy
,
an
d
c
o
n
v
e
n
ien
ce
.
Haz
ar
d
o
u
s
s
ettin
g
s
an
d
wo
r
k
p
lace
s
ca
n
b
e
m
o
r
e
p
r
ec
is
ely
q
u
a
n
tifi
ed
,
a
n
d
r
is
k
s
ca
n
b
e
co
n
tr
o
lled
m
o
r
e
ea
s
ily
.
I
n
cr
ea
s
ed
k
n
o
wled
g
e
a
b
o
u
t
wo
r
k
in
g
cir
cu
m
s
tan
ce
s
en
ab
les
ch
o
ices
to
en
h
an
ce
c
o
m
f
o
r
t
an
d
,
as
a
r
esu
lt,
p
r
o
d
u
ctiv
ity
.
Fo
r
ex
am
p
le,
a
m
o
r
e
lo
ca
lize
d
th
er
m
o
s
tat
m
ay
in
d
icate
te
m
p
er
atu
r
e
v
ar
ian
ce
s
b
etwe
en
th
e
d
if
f
er
e
n
t
ar
ea
s
in
ce
r
tain
wo
r
k
p
lace
s
.
Ad
ju
s
tin
g
th
e
tem
p
er
at
u
r
e
o
r
lig
h
tin
g
in
p
lace
s
th
at
a
r
e
b
ein
g
u
s
e
d
co
u
ld
also
lo
wer
en
er
g
y
e
x
p
en
d
itu
r
e
an
d
in
cr
ea
s
e
efficien
cy
.
Mo
n
o
to
n
o
u
s
ac
tiv
ities
co
u
ld
b
e
au
to
m
at
ed
,
r
esu
ltin
g
in
less
d
o
wn
tim
e
an
d
in
cr
ea
s
ed
p
r
o
d
u
ctiv
ity
,
ac
cu
r
ac
y
,
an
d
o
u
tco
m
es.
L
ev
er
a
g
in
g
th
ese
ad
v
an
tag
es
en
a
b
les
em
p
lo
y
er
s
to
in
cr
ea
s
e
em
p
lo
y
ee
s
atis
f
ac
tio
n
an
d
r
eten
tio
n
,
wh
ich
c
o
u
ld
r
esu
lt
in
in
c
r
ea
s
ed
r
ev
en
u
es
an
d
a
r
ed
u
ctio
n
in
th
e
in
v
estme
n
t
i
n
v
o
lv
e
d
in
s
taff
tu
r
n
o
v
e
r
[
5
]
.
An
o
th
er
p
o
s
s
ib
le
u
s
e
o
f
I
o
T
t
ec
h
n
o
lo
g
y
is
in
th
e
h
o
m
e,
f
o
r
th
e
p
u
r
p
o
s
es
o
f
im
p
r
o
v
in
g
t
h
e
q
u
ality
o
f
life
,
g
r
ea
ter
s
p
en
d
in
g
e
f
f
icien
cy
,
a
n
d
i
n
cr
ea
s
ed
co
n
tr
o
l
o
f
r
eso
u
r
ce
s
.
E
d
g
e
-
b
ased
I
o
T
c
o
m
p
u
tin
g
co
n
n
ec
ts
s
m
ar
t
d
ev
ices,
p
r
o
d
u
cts,
an
d
a
p
p
lian
ce
s
to
th
e
I
n
ter
n
et
to
im
p
r
o
v
e
t
h
e
co
n
s
u
m
er
ex
p
er
ie
n
ce
.
W
ith
o
u
t
a
d
o
u
b
t,
ea
ch
c
h
an
g
e
b
r
in
g
s
with
it
b
o
th
r
ewa
r
d
s
an
d
o
b
s
tacle
s
th
at
m
u
s
t
b
e
f
ac
ed
.
Fo
r
in
s
tan
ce
,
s
ec
u
r
ity
p
o
s
es
a
ch
al
len
g
e
in
th
e
r
ea
lm
o
f
I
o
T
.
I
t
is
ess
en
tial
to
estab
lis
h
an
d
m
ai
n
tain
p
r
in
cip
les
an
d
f
u
n
ctio
n
alities
th
at
en
s
u
r
e
a
n
etwo
r
k
’
s
f
u
n
ctio
n
ality
.
T
h
is
in
clu
d
es
im
p
lem
en
tin
g
m
ea
s
u
r
es
s
u
ch
as
au
th
en
ticatio
n
,
co
n
f
id
en
tiality
,
en
d
-
to
-
e
n
d
s
ec
u
r
ity
,
a
n
d
in
te
g
r
ity
[
7
]
.
W
ith
th
e
g
r
o
wth
o
f
tech
n
o
lo
g
y
an
d
its
wid
esp
r
ea
d
u
s
e,
th
er
e
is
an
in
cr
ea
s
in
g
n
ee
d
f
o
r
s
ec
u
r
e
m
eth
o
d
s
o
f
co
m
m
u
n
icatio
n
a
n
d
p
a
s
s
wo
r
d
s
to
r
ag
e
[
8
]
.
Desp
ite
th
e
ad
v
an
ce
m
en
ts
in
in
ter
n
et
-
co
n
n
ec
ted
d
e
v
ices,
o
n
lin
e
ac
co
u
n
t
p
ass
wo
r
d
s
ar
e
s
till
v
u
ln
er
ab
le
to
th
ef
t,
cr
ac
k
i
n
g
,
a
n
d
h
ac
k
in
g
.
I
t
is
ev
en
p
o
s
s
ib
le
f
o
r
f
r
au
d
s
ter
s
to
p
u
r
c
h
ase
u
s
er
cr
e
d
en
tials
f
r
o
m
o
n
lin
e
m
ed
ia
p
latf
o
r
m
s
.
Nu
m
er
o
u
s
d
ata
b
r
ea
ch
es
h
av
e
o
cc
u
r
r
e
d
g
lo
b
a
lly
,
af
f
ec
tin
g
m
a
n
y
in
ter
n
atio
n
al
o
r
g
an
izatio
n
s
.
T
h
er
ef
o
r
e,
p
ass
wo
r
d
less
au
th
e
n
ticatio
n
f
ac
ilit
ates a
m
o
r
e
s
ec
u
r
e
o
n
lin
e
ac
co
u
n
t lo
g
in
[
9
]
,
[
1
0
]
.
W
ith
r
eg
ar
d
to
th
e
a
d
v
an
ce
m
en
ts
in
s
m
ar
t
h
o
m
e
(
SH)
tec
h
n
o
lo
g
ies,
I
o
T
d
ata
m
u
s
t
b
e
p
r
o
tecte
d
to
en
s
u
r
e
a
h
ig
h
lev
el
o
f
s
ec
u
r
i
ty
an
d
r
ea
s
o
n
ab
le
r
eliab
ilit
y
.
Du
e
to
th
e
in
cr
ea
s
in
g
n
u
m
b
er
o
f
I
o
T
d
e
v
ices,
h
o
wev
er
,
c
u
r
r
e
n
t
ad
d
r
ess
in
g
s
y
s
tem
s
an
d
s
ec
u
r
ity
p
r
o
to
co
ls
m
ay
n
o
t
alwa
y
s
wo
r
k
ef
f
ec
tiv
ely
,
wh
ich
lead
s
to
s
ec
u
r
ity
v
u
ln
e
r
ab
ilit
ies.
T
h
r
o
u
g
h
o
u
t
th
e
d
ev
elo
p
m
en
t
an
d
o
p
er
atio
n
o
f
d
e
v
ices
an
d
h
u
b
s
,
p
r
io
r
itizin
g
s
ec
u
r
ity
m
ea
s
u
r
es
is
p
ar
am
o
u
n
t,
i
n
clu
d
in
g
av
ailab
ilit
y
,
a
u
th
e
n
ticatio
n
,
an
d
k
e
y
m
an
a
g
em
en
t.
E
n
h
an
cin
g
au
th
en
ticatio
n
m
eth
o
d
s
ca
n
p
r
o
v
id
e
a
s
af
e,
u
s
er
-
f
r
ien
d
ly
,
a
n
d
co
n
v
en
ien
t
en
v
ir
o
n
m
en
t
f
o
r
all
ty
p
es
o
f
u
s
er
s
wh
o
wis
h
to
u
s
e
SH I
o
T
s
y
s
te
m
s
.
T
h
is
r
esear
ch
co
n
tr
ib
u
tes
to
t
h
e
b
o
d
y
o
f
k
n
o
wled
g
e
b
y
p
r
o
p
o
s
in
g
a
m
u
ltifa
cto
r
p
ass
wo
r
d
less
s
ec
u
r
e
au
th
en
ticatio
n
s
ch
em
e.
T
h
e
p
r
o
p
o
s
ed
s
ch
em
e
ad
o
p
ts
in
ter
n
e
t
p
r
o
to
co
l
v
e
r
s
io
n
s
ix
(
I
Pv
6
)
a
n
d
p
r
o
v
id
es
a
o
n
e
-
tim
e
p
ass
wo
r
d
(
OT
P),
b
io
m
e
tr
ic
au
th
en
ticatio
n
,
u
s
er
an
d
d
ev
ice
id
en
tific
atio
n
,
a
n
d
an
en
cr
y
p
tio
n
k
ey
.
B
y
d
o
in
g
s
o
,
t
h
e
s
ch
em
e
aim
s
to
ad
d
r
ess
a
b
alan
ce
b
etwe
en
s
ec
u
r
ity
v
er
s
u
s
u
s
ab
ilit
y
,
wh
ic
h
m
ea
n
s
in
cr
ea
s
in
g
s
ec
u
r
ity
wh
ile
r
ed
u
cin
g
co
m
p
lex
ity
.
I
n
ad
d
itio
n
,
th
e
p
r
o
p
o
s
ed
s
ch
em
e
e
n
s
u
r
es
a
o
n
e
-
tim
e
s
etu
p
m
ec
h
a
n
is
m
,
as
well
as
en
ab
lin
g
b
io
m
etr
ic
v
er
ificatio
n
in
m
o
b
ile
p
h
o
n
es
an
d
elim
in
atin
g
th
e
u
s
e
o
f
p
as
s
wo
r
d
s
th
r
o
u
g
h
a
p
ass
wo
r
d
less
au
th
en
ticatio
n
m
eth
o
d
.
T
h
e
r
est
o
f
th
e
p
ap
er
is
o
r
g
a
n
ized
as
f
o
llo
ws.
Sectio
n
2
d
is
cu
s
s
es
r
elate
d
wo
r
k
.
T
h
is
is
f
o
llo
wed
b
y
th
e
d
etails o
f
th
e
m
eth
o
d
o
lo
g
y
in
s
ec
tio
n
3
.
Sectio
n
4
p
r
esen
t
s
th
e
ex
p
er
im
en
tal
r
esu
lts
an
d
r
elate
d
d
is
cu
s
s
io
n
.
Sectio
n
5
co
n
cl
u
d
es th
is
wo
r
k
an
d
o
f
f
er
s
d
ir
ec
tio
n
s
f
o
r
f
u
tu
r
e
wo
r
k
.
2.
RE
L
AT
E
D
WO
RK
I
o
T
is
an
e
m
er
g
in
g
co
n
ce
p
t
th
at
is
in
cr
ea
s
in
g
ly
b
ein
g
ad
o
p
ted
i
n
th
e
c
o
n
tem
p
o
r
ar
y
wir
eless
telec
o
m
m
u
n
icatio
n
s
lan
d
s
ca
p
e
.
T
h
e
u
n
d
er
l
y
in
g
p
r
i
n
cip
le
o
f
t
h
is
co
n
ce
p
t is th
e
u
b
iq
u
ito
u
s
ex
is
ten
ce
o
f
d
iv
er
s
e
en
titi
es
o
r
ar
tifa
cts,
in
clu
d
in
g
r
ad
io
-
f
r
eq
u
e
n
cy
id
en
tific
ati
o
n
(
R
FID
)
tag
s
,
s
en
s
o
r
s
,
ac
t
u
ato
r
s
,
an
d
m
o
b
ile
p
h
o
n
es.
T
h
ese
en
titi
es
p
o
s
s
ess
th
e
ab
ilit
y
to
en
g
ag
e
in
in
ter
ac
tio
n
s
an
d
co
llab
o
r
ate
with
n
eig
h
b
o
r
i
n
g
en
titi
es
to
ac
h
iev
e
s
h
ar
e
d
o
b
jectiv
es th
r
o
u
g
h
d
is
tin
ct
ad
d
r
ess
in
g
m
ec
h
an
is
m
s
[
1
1
]
.
T
h
e
f
u
n
d
a
m
en
tal
ad
v
a
n
tag
e
o
f
I
o
T
id
ea
lies
in
its
s
u
b
s
tan
ti
al
im
p
ac
t
o
n
v
ar
io
u
s
asp
ec
ts
o
f
ev
er
y
d
a
y
life
an
d
th
e
b
eh
a
v
io
r
o
f
p
o
t
en
tial
co
n
s
u
m
er
s
.
I
o
T
is
ex
p
ec
ted
to
h
a
v
e
s
ig
n
if
ican
t
im
p
licatio
n
s
f
o
r
b
o
th
p
r
o
f
ess
io
n
al
an
d
d
o
m
esti
c
d
o
m
ain
s
,
as
p
er
ce
iv
ed
b
y
in
d
iv
id
u
al
u
s
er
s
.
I
n
th
e
g
i
v
en
co
n
tex
t,
p
o
ten
tial
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8
7
0
8
I
n
t J E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
14
,
No
.
6
,
Dec
em
b
e
r
20
24
:
7
1
8
6
-
7
1
9
7
7188
ap
p
licatio
n
s
ce
n
ar
io
s
in
th
e
n
ea
r
f
u
tu
r
e,
s
u
ch
as
h
o
m
e
au
t
o
m
atio
n
,
ass
is
ted
liv
in
g
,
e
-
h
e
alth
,
an
d
en
h
a
n
ce
d
lear
n
in
g
,
r
e
p
r
esen
t
a
lim
ited
s
elec
tio
n
o
f
ex
am
p
les
wh
e
r
ein
th
e
n
ew
p
ar
a
d
ig
m
is
e
x
p
ec
ted
to
h
a
v
e
a
s
u
b
s
tan
tial
im
p
ac
t.
Fro
m
th
e
s
tan
d
p
o
in
t
o
f
a
b
u
s
in
ess
u
s
er
,
th
e
v
alu
e
o
f
t
h
is
p
h
en
o
m
en
o
n
is
p
ar
ticu
lar
l
y
ev
id
en
t
in
v
a
r
io
u
s
f
ield
s
,
i
n
clu
d
in
g
a
u
to
m
atio
n
an
d
in
d
u
s
tr
ial
p
r
o
d
u
ctio
n
,
lo
g
is
tics
,
b
u
s
in
ess
/p
r
o
ce
s
s
m
an
ag
em
en
t,
an
d
t
h
e
in
tellig
en
t
tr
an
s
p
o
r
tatio
n
o
f
p
eo
p
le
a
n
d
th
in
g
s
[
1
1
]
.
Fu
r
th
er
m
o
r
e,
I
o
T
ca
n
b
e
u
s
ed
to
d
ev
elo
p
s
m
ar
t c
ities
,
s
m
ar
t g
r
i
d
s
,
an
d
in
tellig
en
t lo
g
is
tics
[
1
2
]
.
T
h
e
I
n
ter
n
et
h
as
m
ad
e
p
r
o
g
r
e
s
s
o
v
er
th
e
y
ea
r
s
b
y
co
n
n
ec
ti
n
g
b
illi
o
n
s
o
f
n
o
d
es
wo
r
ld
wi
d
e.
T
h
ese
n
o
d
es
co
m
e
in
v
ar
io
u
s
s
izes
an
d
with
d
if
f
er
en
t
ca
p
ab
ilit
i
es
an
d
co
m
p
u
tin
g
ca
p
ac
ities
,
en
ab
lin
g
th
em
to
s
u
p
p
o
r
t
a
wid
e
r
a
n
g
e
o
f
p
o
s
s
ib
le
ap
p
licatio
n
s
.
As
a
r
esu
lt,
th
e
tr
ad
itio
n
al
I
n
ter
n
et
ev
o
lv
e
d
in
to
I
o
T
,
wh
ich
ca
n
n
o
w
co
n
n
ec
t
o
b
jects
an
d
in
c
o
r
p
o
r
ate
in
tellig
en
ce
in
to
th
e
s
y
s
tem
to
an
aly
ze
s
p
ec
if
ic
d
ata
f
r
o
m
o
b
jects
in
tellig
en
tly
an
d
m
ak
e
au
to
n
o
m
o
u
s
d
ec
is
io
n
s
th
at
ar
e
b
en
e
f
icial.
T
h
er
ef
o
r
e,
I
o
T
h
as
th
e
p
o
ten
tial
t
o
cr
ea
t
e
ap
p
licatio
n
s
an
d
s
er
v
ices th
at
u
s
er
s
co
u
ld
n
o
t p
r
ev
i
o
u
s
ly
h
a
v
e
im
ag
in
ed
[
1
3
]
.
As
s
ta
ted
ea
r
lier
,
I
o
T
d
o
es
n
o
t
h
av
e
a
u
n
if
ied
ag
r
ee
d
-
u
p
o
n
d
ef
in
itio
n
.
R
ath
er
,
d
if
f
er
e
n
t
g
r
o
u
p
s
,
s
u
ch
as
ac
ad
em
ics,
r
esear
ch
er
s
,
p
r
ac
titi
o
n
er
s
,
in
n
o
v
ato
r
s
,
d
ev
el
o
p
er
s
,
an
d
b
u
s
in
ess
ex
ec
u
tiv
es,
h
av
e
o
f
f
er
e
d
th
eir
o
wn
in
ter
p
r
etatio
n
s
o
f
th
e
co
n
ce
p
t.
Ho
wev
e
r
,
t
h
e
n
o
tio
n
o
f
I
o
T
is
co
m
m
o
n
ly
attr
ib
u
ted
to
Kev
in
Ash
to
n
,
a
s
p
ec
ialis
t
in
in
n
o
v
atio
n
.
Alth
o
u
g
h
th
ese
g
r
o
u
p
s
h
av
e
d
if
f
er
en
t
d
ef
in
itio
n
s
,
th
e
y
all
ag
r
ee
th
at
th
e
in
itial
iter
atio
n
o
f
th
e
I
n
ter
n
et
p
r
im
ar
ily
r
ev
o
lv
e
d
ar
o
u
n
d
d
ata
p
r
o
d
u
ce
d
b
y
h
u
m
an
s
;
th
e
n
ex
t
v
er
s
io
n
r
ev
o
lv
e
s
ar
o
u
n
d
d
ata
g
en
er
ate
d
b
y
o
b
je
cts
[
1
4
]
.
A
co
m
p
r
e
h
en
s
iv
e
d
e
s
cr
ip
tio
n
o
f
I
o
T
is
th
at
it
is
a
n
etwo
r
k
o
f
d
ev
ices
th
at
ca
n
o
r
g
a
n
ize
th
em
s
elv
es
au
to
n
o
m
o
u
s
ly
.
T
h
ese
d
ev
ic
es
ar
e
ca
p
ab
le
o
f
ex
ch
a
n
g
in
g
in
f
o
r
m
atio
n
an
d
r
eso
u
r
ce
s
am
o
n
g
th
em
s
elv
es,
wh
er
eb
y
th
e
y
ca
n
r
esp
o
n
d
an
d
ad
ap
t to
ev
e
n
ts
an
d
ch
a
n
g
es i
n
th
eir
en
v
ir
o
n
m
e
n
t
[
1
4
]
.
I
n
ter
esti
n
g
ly
,
th
e
co
n
ce
p
t
o
f
I
o
T
wen
t
th
r
o
u
g
h
a
s
er
ies
o
f
im
p
o
r
tan
t
k
e
y
ev
en
ts
,
as
s
u
m
m
ar
ized
in
p
r
ev
io
u
s
r
esear
c
h
[
1
5
]
.
T
h
e
co
n
ce
p
t
o
f
I
o
T
h
as
b
ec
o
m
e
in
c
r
ea
s
in
g
ly
p
o
p
u
lar
an
d
wid
ely
d
is
cu
s
s
ed
in
th
e
in
f
o
r
m
atio
n
tech
n
o
lo
g
y
in
d
u
s
tr
y
.
Ov
e
r
th
e
p
ast
d
ec
ad
e,
f
o
r
e
x
am
p
le,
I
o
T
h
as
g
ain
ed
atten
tio
n
f
o
r
its
v
is
io
n
o
f
a
n
etwo
r
k
in
wh
ich
p
h
y
s
ical
o
b
jects
ca
n
b
e
co
n
n
ec
ted
an
d
co
m
m
u
n
icat
e
with
ea
ch
o
th
er
at
an
y
tim
e
an
d
f
r
o
m
an
y
wh
er
e
[
1
6
]
.
B
y
ass
ig
n
in
g
an
id
e
n
tifie
r
to
ea
ch
o
b
ject,
I
o
T
cr
ea
tes
a
n
etwo
r
k
th
at
f
ac
ilit
ates
co
m
m
u
n
icatio
n
b
etwe
en
h
u
m
an
s
,
b
etwe
en
h
u
m
an
s
an
d
o
b
jects,
an
d
b
etwe
en
th
e
o
b
je
cts
th
em
s
elv
es,
e
s
s
en
tially
co
n
n
ec
tin
g
ev
er
y
t
h
in
g
in
th
e
wo
r
ld
[
1
7
]
.
Use
o
f
I
o
T
en
v
is
io
n
s
a
f
u
tu
r
e
in
w
h
ich
alm
o
s
t
e
v
er
y
th
i
n
g
ca
n
b
e
i
n
ter
co
n
n
ec
te
d
a
n
d
co
m
m
u
n
icate
in
tellig
en
tly
.
W
h
er
ea
s
u
s
er
s
u
s
u
ally
ass
o
ciate
d
a
“
c
o
n
n
ec
tio
n
”
with
d
ev
ice
s
s
u
ch
as
s
er
v
er
s
,
lap
to
p
s
,
tab
lets
,
an
d
p
h
o
n
es,
I
o
T
tak
es
it
f
u
r
th
er
b
y
c
o
n
n
e
ctin
g
s
en
s
o
r
s
an
d
ac
t
u
ato
r
s
e
m
b
ed
d
e
d
in
o
b
jects
s
u
ch
as
r
o
ad
s
o
r
p
ac
em
a
k
er
s
th
r
o
u
g
h
wir
ed
o
r
wir
eless
n
et
wo
r
k
s
,
an
d
s
o
m
etim
es
u
s
in
g
t
h
e
in
ter
n
et
p
r
o
to
c
o
l
(
I
P)
to
co
n
n
ec
t
to
th
e
I
n
ter
n
et.
T
h
e
d
ata
co
llected
b
y
th
ese
n
etwo
r
k
s
ar
e
th
en
s
en
t
to
co
m
p
u
ter
s
f
o
r
an
aly
s
is
.
W
h
en
o
b
jects
ca
n
p
er
ce
iv
e
th
eir
s
u
r
r
o
u
n
d
in
g
s
an
d
co
m
m
u
n
icate
with
in
th
em
,
t
h
ey
b
ec
o
m
e
to
o
ls
f
o
r
u
n
d
er
s
tan
d
i
n
g
co
m
p
lex
ity
a
n
d
r
esp
o
n
d
in
g
q
u
ick
ly
.
T
h
is
tech
n
o
lo
g
ical
ad
v
a
n
ce
m
en
t
h
as
im
p
r
o
v
ed
m
an
y
asp
ec
ts
,
as
it
in
v
o
lv
es
th
e
im
p
lem
e
n
tatio
n
o
f
in
f
o
r
m
atio
n
s
y
s
tem
s
th
at
ca
n
f
u
n
ctio
n
in
d
ep
en
d
en
tly
.
I
n
p
r
ac
tice,
I
o
T
r
ef
er
s
to
th
e
p
r
o
ce
s
s
o
f
co
d
in
g
an
d
co
n
n
ec
tin
g
ev
er
y
d
ay
o
b
jects
s
o
th
at
th
ey
ca
n
b
e
ea
s
ily
id
en
t
if
ied
an
d
tr
ac
k
ed
u
s
in
g
th
e
i
n
ter
n
et
[
1
7
]
.
A
m
aj
o
r
p
ar
t
o
f
th
e
e
x
is
tin
g
co
n
ten
t
r
e
lated
to
I
o
T
h
as
b
ee
n
d
e
v
elo
p
ed
u
s
in
g
R
FID
tag
s
an
d
I
P
ad
d
r
ess
es,
wh
ich
ar
e
co
n
n
ec
ted
t
o
a
n
etwo
r
k
[
1
8
]
.
T
h
e
id
ea
o
f
th
e
s
m
ar
t
h
o
m
e
b
eg
an
in
th
e
late
1
9
6
0
s
,
w
h
en
co
m
p
u
ter
e
n
th
u
s
iast
s
,
s
u
ch
as
J
im
Su
th
er
lan
d
,
b
eg
a
n
i
n
s
tallin
g
c
o
m
p
u
ter
s
i
n
th
ei
r
h
o
m
es
f
o
r
v
ar
io
u
s
r
ea
s
o
n
s
[
1
9
]
.
W
h
en
p
er
s
o
n
al
co
m
p
u
ter
s
b
ec
am
e
wid
ely
av
ailab
le
in
th
e
late
1
9
7
0
s
,
th
e
o
n
-
s
ite
co
n
tr
o
l
an
d
au
t
o
m
atio
n
o
f
h
o
u
s
eh
o
ld
ap
p
lian
ce
s
attr
ac
ted
en
th
u
s
iast
s
.
At
a
tim
e
wh
en
a
d
o
m
esti
c
I
n
ter
n
e
t
s
er
v
ice
was
n
o
t
y
et
wid
ely
ac
ce
s
s
ib
le,
r
em
o
te
co
n
tr
o
l
was
ac
co
m
p
lis
h
ed
v
i
a
d
ec
o
d
in
g
d
u
al
-
to
n
e
m
u
lti
-
f
r
eq
u
en
cy
s
ig
n
als
s
en
t
o
v
er
tel
ep
h
o
n
e
lin
es
[
1
9
]
.
Alth
o
u
g
h
r
esear
c
h
in
to
s
m
ar
t
h
o
m
es
h
as
ad
v
an
ce
d
,
ac
tu
a
l
u
s
e
r
em
ain
s
v
er
y
lim
ited
.
Gr
eich
en
[
2
0
]
,
th
e
d
ev
elo
p
m
e
n
t
o
f
th
e
SH
m
ar
k
e
t
ca
m
e
af
ter
a
d
ec
ad
e
o
f
s
tu
d
y
an
d
d
ep
lo
y
m
en
t.
Alth
o
u
g
h
it
is
an
ticip
ated
th
at
o
th
er
n
ee
d
s
m
ay
em
er
g
e
as
th
e
co
n
ce
p
t
o
f
th
e
s
m
ar
t
h
o
m
e
m
atu
r
es,
th
e
k
ey
r
eq
u
i
r
em
e
n
ts
d
eter
m
in
ed
in
p
r
ev
io
u
s
r
esear
ch
in
cl
u
d
e
h
eter
o
g
en
eity
,
s
elf
-
co
n
fig
u
r
a
b
i
lity
,
ex
ten
s
ib
ilit
y
,
co
n
tex
t
a
war
en
ess
,
u
s
ab
ilit
y
,
s
ec
u
r
ity
an
d
p
r
iv
ac
y
p
r
o
tectio
n
,
as we
ll a
s
in
tellig
en
ce
[
1
9
]
.
Stalli
n
g
s
et
a
l.
[
2
1
]
n
o
ted
th
at
in
s
u
f
f
icien
t
co
n
f
id
e
n
tiality
,
in
teg
r
ity
,
an
d
s
ec
u
r
ity
o
f
d
ata
in
I
o
T
ca
n
p
o
ten
tially
jeo
p
ar
d
ize
th
e
tec
h
n
o
lo
g
y
’
s
b
r
o
ad
ad
o
p
tio
n
.
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k
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attac
k
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ca
n
also
co
n
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o
l
h
o
w
th
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d
ev
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d
f
o
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s
in
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m
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I
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T
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Dig
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I
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:
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ii
)
s
o
m
eth
in
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p
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s
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p
o
s
s
ess
es
,
iii
)
a
p
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ical
ch
ar
ac
ter
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p
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i.e
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am
ic
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W
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as
m
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ltifa
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ate.
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m
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ar
e
b
eliev
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d
to
b
e
ev
en
s
tr
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n
g
e
r
[
2
1
]
.
Nu
m
e
r
o
u
s
s
tu
d
ies
h
av
e
b
ee
n
co
n
d
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d
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h
en
ticatio
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s
y
s
tem
s
.
E
ac
h
s
tu
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y
ex
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lo
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th
en
ticatio
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f
r
o
m
a
v
ar
iety
o
f
p
er
s
p
ec
tiv
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Fo
r
in
s
tan
ce
,
o
n
e
co
m
p
r
eh
en
s
iv
e
o
v
er
v
iew
o
f
ex
is
tin
g
r
esear
c
h
e
r
s
ch
em
es c
o
n
s
id
er
ed
c
r
iter
ia
an
d
co
m
m
o
n
alities
[
2
2
]
.
I
n
ass
ess
in
g
wh
at
a
p
er
s
o
n
k
n
o
ws,
o
n
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tu
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y
[
1
2
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co
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p
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v
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s
ch
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etail
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ch
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r
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ap
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[
2
3
]
,
wh
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p
r
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th
e
i
d
ea
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f
h
av
in
g
a
co
n
tr
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l
s
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v
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f
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m
u
ltip
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clo
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d
s
er
v
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T
h
e
co
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tr
o
l
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v
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wo
u
ld
en
s
u
r
e
a
u
th
en
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wh
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th
e
clo
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d
s
er
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s
wer
e
s
p
r
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d
o
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t
.
T
o
ass
ess
th
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au
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en
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,
p
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d
,
a
n
d
id
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m
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g
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ca
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r
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im
p
lem
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ix
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r
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o
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th
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p
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atin
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s
ch
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ed
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r
e
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SR
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th
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in
ter
n
et
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f
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s
I
Pv
6
-
o
v
er
-
L
o
W
PAN
(
6
L
o
W
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b
ased
I
o
T
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etwo
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k
s
[
2
4
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.
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6
L
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ased
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o
T
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s
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h
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tech
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m
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au
th
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d
k
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m
en
t
p
r
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d
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r
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s
in
g
a
lig
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t,
s
ec
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r
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h
ash
alg
o
r
ith
m
(
SHA
-
1
6
0
)
an
d
an
ad
v
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ce
d
en
cr
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p
tio
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s
tan
d
ar
d
(
AE
S
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1
9
2
)
.
A
n
o
v
el
r
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te
u
s
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au
th
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n
ticatio
n
(
R
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tech
n
iq
u
e
f
o
r
u
s
in
g
s
m
ar
t
ca
r
d
s
to
au
th
e
n
ticate
u
s
er
s
in
wir
eless
s
en
s
o
r
n
etwo
r
k
s
h
as
also
b
ee
n
d
is
cu
s
s
ed
[
2
5
]
.
T
h
e
r
esear
ch
er
s
f
o
u
n
d
th
at
s
m
ar
t
ca
r
d
s
co
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ld
au
th
en
ticate
an
d
o
p
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ate
I
o
T
d
ev
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b
y
ca
lcu
latin
g
a
s
ess
i
o
n
k
e
y
f
r
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m
th
e
a
u
th
en
ticatio
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k
ey
.
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n
th
e
s
am
e
co
n
tex
t,
o
th
er
r
esear
c
h
p
r
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p
o
s
ed
an
au
th
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n
ticatio
n
s
ch
em
e
b
ased
o
n
R
UA
f
o
r
clo
u
d
-
I
o
T
ap
p
licatio
n
s
[
2
6
]
,
[
2
7
]
.
T
h
e
s
y
s
tem
’
s
s
ec
u
r
ity
d
ef
en
s
es
h
av
e
s
ix
s
tag
es:
p
r
e
-
co
m
p
u
tatio
n
,
r
e
g
is
tr
atio
n
,
lo
g
in
,
au
t
h
en
ticatio
n
,
p
ass
wo
r
d
ch
an
g
e
,
an
d
s
m
ar
t c
ar
d
r
ev
o
ca
tio
n
.
Ku
m
ar
an
d
C
h
o
u
h
an
[
2
8
]
p
r
o
p
o
s
e
a
s
m
ar
t
ca
r
d
-
b
ased
s
ec
u
r
e
ad
d
r
ess
in
g
an
d
au
t
h
en
ticatio
n
(
SC
SAA)
m
eth
o
d
th
at
u
s
es
s
m
ar
t
ca
r
d
s
to
g
iv
e
SH
ap
p
lia
n
ce
s
an
d
d
e
v
ices
in
d
iv
id
u
al
a
d
d
r
ess
es.
T
h
e
m
ain
co
n
tr
ib
u
tio
n
o
f
th
eir
wo
r
k
is
d
iv
id
ed
in
to
two
p
a
r
ts
:
s
ec
u
r
e
ad
d
r
ess
in
g
an
d
s
ec
u
r
e
a
u
th
en
ticatio
n
.
T
h
eir
m
eth
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d
u
s
es
a
g
o
o
d
b
alan
ce
b
etwe
en
an
ad
d
r
ess
in
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s
ch
em
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d
an
au
th
en
ticatio
n
s
ch
e
m
e
th
at
ad
o
p
ts
th
e
m
o
b
ile
I
Pv
6
an
d
a
s
ec
u
r
e
s
ch
em
e
u
tili
zin
g
m
u
ltifa
cto
r
au
th
en
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v
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a
s
m
ar
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c
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d
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r
d
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d
b
io
m
etr
ics.
T
h
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m
eth
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d
f
o
c
u
s
es
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n
SH
I
o
T
ap
p
licatio
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s
an
d
h
o
w
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s
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s
to
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tr
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l
I
o
T
d
ev
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ec
u
r
ely
.
A
d
is
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id
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is
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if
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u
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6
4
-
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it
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D
(
I
I
D)
.
Fo
r
a
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p
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ests
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p
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I
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h
ich
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th
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6
4
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I
Pv
6
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o
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Su
b
s
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tly
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I
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t
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at
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ch
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n
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e
-
s
to
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th
e
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er
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d
atab
as
e.
T
h
e
h
o
m
e
s
er
v
er
s
to
r
es
th
is
6
4
-
b
it
o
b
ject
d
u
r
i
n
g
th
e
r
eg
is
tr
atio
n
p
r
o
ce
s
s
an
d
s
en
d
s
it
to
th
e
u
s
er
e
n
d
v
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a
s
m
ar
t
ca
r
d
.
Ku
m
ar
an
d
C
h
o
u
h
a
n
[
2
8
]
lo
g
in
au
th
en
ticatio
n
p
h
ase
is
tr
ig
g
er
ed
wh
en
th
e
u
s
er
r
ec
eiv
es
th
e
s
m
ar
t
ca
r
d
an
d
s
ess
io
n
k
ey
.
T
h
e
l
o
g
in
a
n
d
a
u
th
en
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n
p
r
o
ce
d
u
r
e
ar
e
b
ased
o
n
m
u
ltifa
cto
r
au
th
en
ticati
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n
,
wh
ich
in
clu
d
es
th
r
ee
ch
ar
ac
ter
is
tics
:
f
ir
s
t,
s
o
m
eth
in
g
y
o
u
k
n
o
w
(
th
e
p
ass
wo
r
d
)
;
s
ec
o
n
d
,
s
o
m
eth
in
g
y
o
u
a
r
e
(
b
io
m
etr
ics);
an
d
th
ir
d
,
s
o
m
eth
in
g
y
o
u
h
a
v
e
(
th
e
s
m
ar
t c
ar
d
)
.
T
h
e
au
th
en
ticatio
n
s
ch
e
m
e
p
r
o
p
o
s
ed
in
th
e
c
u
r
r
e
n
t
p
ap
er
is
an
en
h
an
ce
m
en
t
o
f
K
u
m
ar
an
d
C
h
o
u
h
an
[
2
8
]
s
ch
em
e
,
wh
ich
was
p
r
o
p
o
s
ed
to
e
n
ab
le
ed
g
e
I
o
T
-
b
ased
SH
d
ev
ices
to
m
an
ag
e
au
th
en
ticatio
n
b
y
p
r
esen
tin
g
th
e
SC
SAA
m
eth
o
d
.
I
n
th
is
r
esear
ch
,
th
e
s
m
ar
t c
ar
d
m
o
d
el
is
en
h
an
ce
d
th
r
o
u
g
h
a
m
o
b
ile
p
h
o
n
e
b
y
ad
d
in
g
an
e
x
tr
a
lay
er
o
f
p
r
o
tectio
n
,
an
OT
P,
wh
ile
m
ain
tain
in
g
b
etter
u
s
er
u
s
ab
ilit
y
b
y
u
tili
zin
g
th
e
en
cr
y
p
tio
n
m
eth
o
d
th
r
o
u
g
h
a
u
s
er
au
t
h
en
ticatio
n
s
er
v
er
(
UAS)
to
p
r
o
v
id
e
a
m
u
ch
m
o
r
e
co
n
v
en
ien
t
p
ass
wo
r
d
less
au
th
en
ticatio
n
m
eth
o
d
o
l
o
g
y
.
T
h
e
r
ef
o
r
e,
th
is
r
esear
ch
p
r
o
p
o
s
es
a
m
u
ltifa
cto
r
p
ass
wo
r
d
less
s
ec
u
r
e
au
th
e
n
ticatio
n
s
ch
em
e
th
at
u
s
es
I
Pv
6
a
n
d
will
p
r
o
v
id
e
an
OT
P,
b
io
m
etr
ic
a
u
th
en
ticatio
n
,
u
s
er
an
d
d
ev
ice
id
en
tific
atio
n
,
an
d
en
cr
y
p
tio
n
k
ey
f
o
r
p
ass
wo
r
d
less
au
th
en
ticatio
n
.
3.
M
E
T
H
O
D
As
s
tated
ea
r
lier
,
th
is
r
esear
c
h
b
u
ild
s
o
n
Ku
m
ar
an
d
C
h
o
u
h
an
[
2
8
]
s
ch
em
e.
H
o
wev
er
,
in
s
tead
o
f
u
s
in
g
a
s
m
ar
t
ca
r
d
,
th
e
p
r
o
p
o
s
ed
au
th
en
ticatio
n
d
ep
en
d
s
o
n
th
e
m
o
b
ile
p
h
o
n
e
s
u
b
s
cr
i
b
er
id
en
tity
m
o
d
u
le
(
SIM
)
ca
r
d
f
o
r
u
s
er
r
eg
is
tr
a
tio
n
.
I
t
also
r
elies
o
n
a
m
o
b
ile
au
th
en
ticato
r
ap
p
licatio
n
to
p
r
o
v
id
e
lo
g
in
au
th
en
ticatio
n
u
s
in
g
OT
P
o
r
b
io
m
etr
ics
,
wh
ich
ca
n
b
e
l
im
ited
b
y
th
e
s
m
ar
t
p
h
o
n
e
c
ap
ab
ilit
y
o
f
eith
e
r
fin
g
er
p
r
in
t
o
r
f
ac
e
r
ec
o
g
n
itio
n
.
As
s
h
o
wn
i
n
Fig
u
r
e
1
,
th
e
m
ain
d
iffer
en
ce
b
etwe
en
K
u
m
ar
an
d
C
h
o
u
h
a
n
[
2
8
]
s
ch
em
e
an
d
th
e
s
ch
em
e
p
r
o
p
o
s
ed
in
th
is
r
esear
ch
is
m
o
b
ile
p
h
o
n
e
en
ab
lem
e
n
t,
wh
ic
h
will
in
cr
ea
s
e
th
e
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8
7
0
8
I
n
t J E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
14
,
No
.
6
,
Dec
em
b
e
r
20
24
:
7
1
8
6
-
7
1
9
7
7190
u
s
ab
ilit
y
an
d
s
ec
u
r
ity
o
f
u
s
in
g
an
d
co
n
tr
o
llin
g
SH
d
e
v
ices
an
d
en
titi
es.
T
h
e
p
r
o
p
o
s
ed
a
u
t
h
en
ticatio
n
s
ch
em
e
h
as fiv
e
m
ain
co
m
p
o
n
e
n
ts
:
a.
Ho
m
e
g
atew
ay
: E
n
a
b
les th
e
d
ev
ice
to
co
n
n
ec
t to
th
e
I
n
ter
n
e
t in
a
h
o
m
e
n
etwo
r
k
.
b.
UAS:
Sto
r
es
u
s
er
in
f
o
r
m
atio
n
s
u
ch
as
m
o
b
ile
d
e
v
ice
I
D,
u
s
er
I
D,
I
P
ad
d
r
ess
,
an
d
a
p
u
b
lic
k
ey
f
o
r
au
th
en
ticatio
n
p
u
r
p
o
s
es.
c.
E
d
g
e
n
o
d
e
s
e
r
v
er
(
E
NS)
:
Acts
as
a
ce
n
tr
alize
d
s
er
v
er
f
o
r
co
n
tr
o
llin
g
an
d
m
o
n
ito
r
in
g
asp
ec
ts
o
f
th
e
SH sy
s
tem
.
d.
Sm
ar
t
home
s
er
v
e
r
(
SHS):
A
s
s
ig
n
s
ad
d
r
ess
es
an
d
id
en
tifie
s
all
SH
d
ev
ices/ap
p
lian
ce
s
.
I
t
also
h
an
d
les
th
e
en
cr
y
p
tio
n
an
d
d
ec
r
y
p
tio
n
o
f
d
ata
p
ac
k
ets.
New
u
s
er
s
c
an
o
n
l
y
r
e
g
is
ter
o
n
ce
th
ey
ar
e
s
u
cc
ess
f
u
lly
v
alid
ated
b
y
th
e
SHS.
e.
Sm
ar
t
h
o
m
e
m
o
b
ile
ap
p
licatio
n
:
Ser
v
es
as
th
e
p
latf
o
r
m
u
p
o
n
w
h
ich
u
s
er
s
in
te
r
ac
t
an
d
co
m
m
u
n
icate
with
th
e
SHS an
d
th
eir
co
n
n
ec
ted
d
ev
ices.
Fig
u
r
e
1
.
C
o
m
p
a
r
is
o
n
o
f
Ku
m
ar
an
d
C
h
o
u
h
an
[
2
8
]
au
th
e
n
ticatio
n
ap
p
r
o
ac
h
a
n
d
th
e
p
r
o
p
o
s
ed
s
ch
em
e
As
s
u
g
g
ested
in
Fig
u
r
e
1
,
Ku
m
ar
an
d
C
h
o
u
h
an
[
2
8
]
a
u
th
e
n
ticatio
n
s
ch
em
e
co
n
s
is
ts
o
f
s
ix
p
h
ases
:
in
itial
p
h
ase,
ad
d
r
ess
in
g
p
h
ase,
r
eg
is
tr
atio
n
p
h
ase,
lo
g
in
au
th
en
ticatio
n
p
h
ase,
s
ess
io
n
ag
r
ee
m
en
t
p
h
ase,
an
d
p
ass
wo
r
d
u
p
d
ate
p
h
ase
.
T
h
e
p
r
o
p
o
s
ed
au
th
e
n
ticatio
n
s
ch
e
m
e
u
s
es
b
o
th
th
e
in
itial
p
h
ase
an
d
t
h
e
ad
d
r
ess
in
g
p
h
ase
with
o
u
t a
n
y
m
o
d
i
f
icatio
n
s
.
Ho
wev
er
,
as th
e
p
r
o
p
o
s
ed
s
o
lu
tio
n
is
a
p
ass
wo
r
d
less
au
th
en
ticatio
n
s
ch
em
e,
th
e
last
p
h
ase
wa
s
r
em
o
v
ed
.
I
n
ad
d
itio
n
,
th
e
r
e
g
is
tr
atio
n
,
lo
g
in
,
an
d
s
ess
io
n
ag
r
ee
m
en
t
p
h
ases
wer
e
en
h
an
ce
d
as f
o
llo
ws.
3
.
1
.
Su
m
m
a
ry
o
f
t
he
enha
ncem
e
nt
o
f
t
he
re
g
is
t
ra
t
i
o
n pha
s
e
I
n
th
e
p
r
o
p
o
s
ed
a
u
th
en
ticatio
n
s
ch
em
e,
th
e
u
s
er
m
a
k
es
a
r
eq
u
est
to
th
e
SH
m
o
b
ile
ap
p
l
icatio
n
v
ia
th
e
u
s
er
’
s
SIM
ca
r
d
,
w
h
er
eb
y
th
e
UAS
r
ec
eiv
es
th
e
r
eg
is
tr
atio
n
r
eq
u
est
an
d
s
en
d
s
an
OT
P
ask
in
g
f
o
r
u
s
er
v
er
ificatio
n
.
T
h
e
OT
P
will
ex
p
ir
e
af
ter
6
0
s
ec
o
n
d
s
if
th
e
u
s
er
is
n
o
t
v
er
if
ied
.
T
h
e
SH
m
o
b
ile
ap
p
licatio
n
will
s
en
d
th
e
d
ev
ice
I
D
an
d
th
e
u
s
e
r
’
s
p
u
b
lic
k
e
y
f
o
r
f
u
t
u
r
e
p
ass
wo
r
d
less
au
th
en
ticatio
n
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2088
-
8
7
0
8
E
d
g
e
in
tern
et
o
f th
i
n
g
s
b
a
s
ed
s
ma
r
t h
o
me
p
a
s
s
w
o
r
d
les
s
a
u
th
en
tica
tio
n
(
Ma
h
a
Hela
l
)
7191
3
.
2
.
Su
m
m
a
ry
o
f
t
he
enha
ncem
e
nt
o
f
t
he
lo
g
in a
uthent
ica
t
io
n pha
s
e
As
ex
p
lain
ed
in
th
e
r
e
g
is
tr
atio
n
p
h
ase,
th
e
u
s
er
will
u
s
e
a
r
eg
is
ter
ed
m
o
b
ile
p
h
o
n
e
f
o
r
a
n
y
f
u
r
th
er
u
s
er
lo
g
in
attem
p
ts
to
th
e
SH n
etwo
r
k
.
I
n
th
e
l
o
g
in
p
h
ase,
th
e
u
s
er
will p
er
f
o
r
m
th
e
f
o
llo
win
g
s
tep
s
:
a.
T
h
e
u
s
er
will
lo
g
in
th
r
o
u
g
h
th
e
SH
m
o
b
ile
ap
p
licatio
n
an
d
s
en
d
th
e
r
eg
is
ter
ed
p
u
b
lic
k
ey
to
th
e
UAS
alo
n
g
with
t
h
e
b
io
m
etr
ic
v
er
i
ficatio
n
r
esu
lt
f
r
o
m
th
e
m
o
b
il
e
p
h
o
n
e.
T
h
e
UAS
will
v
er
if
y
th
e
in
f
o
r
m
atio
n
r
ec
eiv
ed
.
I
f
it
is
n
o
t
c
o
r
r
ec
t,
t
h
e
UAS
will
s
en
d
an
er
r
o
r
m
e
s
s
ag
e
to
th
e
u
s
er
.
I
f
it
is
c
o
r
r
e
ct,
th
e
UAS
will
g
en
er
ate
a
n
ew
s
ess
io
n
with
an
ex
p
ir
y
tim
e
lim
it
o
f
60
s
ec
o
n
d
s
,
th
en
e
n
cr
y
p
t
it
u
s
in
g
th
e
u
s
er
p
u
b
lic
k
ey
,
an
d
s
en
d
th
e
s
ess
io
n
in
f
o
r
m
ati
o
n
to
th
e
u
s
er
.
b.
T
h
e
u
s
er
will
d
ec
r
y
p
t
th
e
m
ess
ag
e
u
s
in
g
a
p
r
iv
ate
k
ey
,
th
en
tak
e
th
e
s
es
s
io
n
I
D
an
d
in
itia
te
a
co
n
n
ec
tio
n
with
th
e
E
NS th
at
h
as th
e
u
s
er
d
ev
ice
I
D
b
e
f
o
r
e
t
h
e
s
ess
io
n
ex
p
ir
es.
c.
T
h
e
E
NS
will
v
alid
ate
th
e
s
ess
io
n
f
r
o
m
th
e
UAS
an
d
a
d
d
th
e
u
s
er
d
ev
ice
I
D
to
th
e
5
6
-
b
its
in
th
e
ad
d
r
ess
in
g
s
ch
em
e
to
allo
w
th
e
u
s
er
ac
ce
s
s
to
th
e
S
H
d
ev
ices/ap
p
lian
ce
s
an
d
s
av
e
th
e
s
es
s
io
n
in
d
etail
in
th
e
SHS.
T
h
e
b
io
m
etr
ic
v
er
ificatio
n
ca
n
n
o
t
b
e
m
is
u
s
ed
d
u
e
t
o
th
e
Go
o
g
le
An
d
r
o
id
o
r
Ap
p
le
iOS
m
o
b
ile
p
h
o
n
e
o
p
e
r
atin
g
s
y
s
tem
[
2
9
]
.
T
h
e
a
p
p
licatio
n
m
u
s
t
in
clu
d
e
a
s
af
eg
u
a
r
d
o
r
en
c
r
y
p
tio
n
t
o
p
r
o
tect
b
io
m
etr
ic
d
ata
f
r
o
m
f
r
au
d
s
ter
attac
k
s
,
r
o
b
u
s
t
r
eg
is
tr
atio
n
p
r
o
ce
d
u
r
es,
a
n
d
p
o
licies
to
p
r
o
tect
d
ata
d
u
r
in
g
tr
an
s
m
is
s
io
n
to
an
d
s
to
r
ag
e
o
n
co
m
p
u
ter
s
er
v
er
s
an
d
to
s
tr
en
g
th
en
b
io
m
e
tr
ic
au
th
en
ticatio
n
.
T
h
e
alg
o
r
ith
m
also
ex
am
in
es
wh
eth
er
th
e
s
cr
ee
n
h
as
r
em
ain
ed
s
tatic
o
v
er
a
ce
r
tain
p
er
io
d
o
f
tim
e.
W
h
en
th
e
u
s
er
lo
g
s
o
u
t
o
r
th
e
tim
e
lim
it
ex
p
ir
es,
th
e
s
y
s
tem
r
e
-
a
u
th
en
ticates
th
e
u
s
er
u
s
in
g
th
at
in
d
iv
id
u
al’
s
f
i
n
g
er
p
r
in
t,
an
d
th
e
u
s
er
ca
n
s
et
th
e
s
ess
io
n
tim
eo
u
t a
cc
o
r
d
in
g
to
p
r
ef
er
en
ce
[
3
0
]
.
3
.
3
.
Su
m
m
a
ry
o
f
t
he
enha
ncem
e
nt
o
f
t
he
s
ess
io
n a
g
re
em
ent
ph
a
s
e
T
h
is
p
h
ase
s
h
o
ws
h
o
w
to
s
af
eg
u
ar
d
n
etwo
r
k
c
o
n
n
ec
tio
n
s
an
d
co
n
s
tr
u
ct
a
s
ess
io
n
k
ey
ag
r
ee
m
en
t
u
s
in
g
s
h
ar
ed
s
ess
io
n
k
ey
s
.
Af
ter
r
eg
is
tr
atio
n
,
ad
d
r
ess
in
g
,
an
d
lo
g
in
au
th
en
ticatio
n
,
th
e
s
ess
io
n
k
ey
ag
r
ee
m
en
t
s
tag
e
p
r
o
tects
I
o
T
n
etwo
r
k
p
r
iv
ac
y
an
d
s
ec
u
r
ity
v
ia
p
s
eu
d
o
-
id
e
n
titi
es
[
2
8
]
.
T
h
e
u
s
er
r
etr
iev
es
th
e
p
r
io
r
s
ess
io
n
k
ey
f
r
o
m
a
m
ess
ag
e
an
d
v
er
if
ies
th
e
id
en
tity
with
th
e
SH
m
o
b
ile
ap
p
.
Valid
s
es
s
io
n
s
co
n
tin
u
e
an
d
in
v
alid
s
ess
io
n
s
ar
e
d
is
ca
r
d
ed
.
4.
RE
SU
L
T
S AN
D
D
I
SCU
SS
I
O
N
T
h
is
s
ec
tio
n
d
is
cu
s
s
e
s
h
o
w
t
h
e
p
r
o
p
o
s
ed
au
th
en
ticatio
n
s
ch
em
e
b
eh
av
e
d
wh
en
v
a
r
io
u
s
ty
p
es
o
f
attac
k
s
wer
e
d
etec
ted
.
T
h
e
s
ec
tio
n
th
en
a
n
aly
ze
s
th
e
p
er
f
o
r
m
an
ce
o
f
th
e
p
r
o
p
o
s
ed
au
th
e
n
ticatio
n
s
ch
em
e
an
d
p
r
o
v
id
es a
c
o
m
p
ar
ativ
e
an
aly
s
is
b
etwe
en
th
e
ex
is
tin
g
au
th
e
n
ticatio
n
s
ch
em
e
an
d
t
h
e
p
r
o
p
o
s
ed
o
n
e.
4
.
1
.
Sim
ula
t
io
n c
o
nfig
ura
t
io
n a
n
d set
up
Au
to
m
ated
v
alid
atio
n
o
f
in
te
r
n
et
s
ec
u
r
ity
p
r
o
to
co
ls
an
d
ap
p
licatio
n
s
(
AVI
SP
A)
is
a
to
o
l
th
at
aim
s
t
o
ev
alu
ate
in
ter
n
et
s
ec
u
r
ity
p
r
o
t
o
co
ls
an
d
ap
p
licatio
n
s
.
I
t
u
tili
ze
s
th
e
h
ig
h
-
lev
el
p
r
o
to
co
l
s
p
ec
if
icatio
n
lan
g
u
ag
e
(
HL
PS
L
)
f
o
r
en
co
d
in
g
.
HL
P
SL
is
a
m
o
d
elin
g
lan
g
u
a
g
e
s
p
ec
if
ically
d
esig
n
ed
f
o
r
s
ec
u
r
ity
p
r
o
to
co
ls
an
d
co
m
m
u
n
icatio
n
.
I
t
d
e
f
in
es
th
e
ch
ar
ac
ter
is
tics
o
f
ea
ch
p
ar
tic
ip
an
t
in
a
s
ce
n
ar
io
with
ea
ch
r
o
le
b
ein
g
d
is
tin
ct
f
r
o
m
t
h
e
o
th
e
r
s
.
R
o
les
r
ec
eiv
e
d
ata
f
r
o
m
p
ar
am
eter
s
an
d
co
m
m
u
n
icate
with
o
th
er
r
o
les
th
r
o
u
g
h
ch
a
n
n
els.
T
h
e
HL
PS
L
2
I
F
co
n
v
er
ter
is
u
s
ed
t
o
co
n
v
e
r
t
an
HL
PS
L
p
r
o
t
o
co
l
in
to
a
s
tan
d
ar
d
i
n
ter
m
ed
iate
f
o
r
m
at
(
I
F).
T
h
is
I
F
s
tan
d
ar
d
s
er
v
es
as
in
p
u
t
to
o
n
e
o
f
f
o
u
r
b
ac
k
e
n
d
s
:
i
)
On
-
t
h
e
-
f
ly
m
o
d
el
-
ch
ec
k
er
(
OFMC
)
,
ii
)
T
r
ee
a
u
to
m
ata
b
ased
o
n
au
to
m
atic
ap
p
r
o
x
im
a
tio
n
s
f
o
r
th
e
an
aly
s
is
o
f
s
ec
u
r
i
ty
p
r
o
to
c
o
ls
(
T
A4
SP
)
,
iii
)
C
o
n
s
tr
ain
t
-
lo
g
ic
-
b
ased
attac
k
s
ea
r
ch
er
(
CL
-
AtSe
)
,
o
r
iv
)
SAT
-
b
ased
m
o
d
el
c
h
ec
k
e
r
(
SATM
C
)
.
T
h
ese
b
ac
k
en
d
s
g
en
er
ate
a
n
o
u
tp
u
t
f
o
r
m
at
(
OF)
b
ased
o
n
t
h
eir
an
aly
s
is
.
T
h
e
p
r
o
p
o
s
ed
s
ch
em
e
also
ad
o
p
ts
th
e
well
-
k
n
o
w
n
Do
le
v
–
Yao
(
DY)
th
r
ea
t
m
o
d
el
[
2
8
]
,
wh
ich
o
r
ig
in
ated
in
1
9
8
3
an
d
is
s
till
co
m
m
o
n
l
y
u
s
ed
in
p
r
o
to
co
l e
v
alu
atio
n
.
I
n
t
h
is
m
o
d
el,
th
e
n
et
wo
r
k
is
s
h
o
wn
as a
s
tar
,
with
th
e
attac
k
er
as
th
e
ce
n
ter
n
o
d
e.
Acc
o
r
d
in
g
l
y
,
all
co
m
m
u
n
icatio
n
is
m
ed
iated
b
y
th
e
attac
k
er
,
wh
o
ca
n
alter
m
ess
ag
es,
p
r
e
v
en
t
t
h
em
f
r
o
m
r
ea
ch
in
g
th
eir
in
ten
d
ed
d
esti
n
atio
n
,
o
r
d
eliv
er
th
e
m
in
tact
[
3
0
]
.
Un
d
er
th
e
DY
m
o
d
el,
o
p
p
o
n
e
n
ts
ca
n
ex
ec
u
te
a
wid
e
v
ar
iety
o
f
d
if
f
er
en
t
ass
au
lts
.
T
h
e
o
p
p
o
n
en
t
em
p
l
o
y
s
an
ag
g
r
ess
iv
e
o
r
p
ass
iv
e
ass
au
lt
th
at
s
ev
er
ely
co
m
p
r
o
m
is
es
th
e
s
y
s
tem
an
d
co
u
ld
also
co
u
n
ter
f
eit,
alter
,
o
r
d
elete
th
e
co
m
m
u
n
icatio
n
r
ec
ei
v
ed
.
I
n
th
e
p
r
o
p
o
s
ed
s
ch
em
e,
r
o
le
s
ar
e
co
n
s
id
er
e
d
in
th
e
s
y
s
te
m
,
in
clu
d
i
n
g
t
h
e
User
,
E
NS
,
SHS
,
an
d
UAS
.
Util
izin
g
th
e
DY
th
r
ea
t
m
o
d
el,
s
ev
er
al
p
h
ases
ar
e
ev
alu
ated
o
n
HL
SP
L
u
s
in
g
th
e
s
h
ar
in
g
o
f
a
s
ess
io
n
k
ey
(
SK)
in
th
e
p
r
o
p
o
s
ed
s
ch
em
e.
T
o
en
s
u
r
e
s
ec
u
r
ity
,
th
e
p
r
o
p
o
s
ed
s
ch
em
e’
s
r
o
les
ar
e
ass
es
s
ed
u
s
in
g
th
e
AVI
SP
A
to
o
l
with
C
L
-
AtSe
b
ac
k
en
d
s
.
T
h
is
allo
ws
tr
u
s
ted
u
s
er
s
to
v
alid
ate
s
ec
u
r
ity
in
th
e
p
r
esen
ce
o
f
attac
k
er
s
an
d
p
r
e
v
en
ts
r
e
p
lay
attac
k
s
.
T
h
e
p
r
o
to
c
o
l
s
cr
ip
t
is
d
esig
n
ed
i
n
s
u
ch
a
wa
y
th
at
t
h
ese
attac
k
s
ca
n
n
o
t
co
m
p
r
o
m
is
e
s
ec
u
r
ity
.
B
y
u
til
izin
g
th
e
C
L
-
AtSe
m
o
d
el
ch
ec
k
er
,
all
d
ef
in
ed
r
o
les
m
ee
t
th
e
r
eq
u
ir
em
en
ts
.
Fig
u
r
e
s
2
(
a)
an
d
2
(
b
)
p
r
esen
t a
s
cr
ee
n
s
h
o
t
f
r
o
m
th
e
s
im
u
latio
n
illu
s
tr
atin
g
h
o
w
ea
ch
s
ess
i
o
n
an
d
en
v
i
r
o
n
m
e
n
t
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8
7
0
8
I
n
t J E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
14
,
No
.
6
,
Dec
em
b
e
r
20
24
:
7
1
8
6
-
7
1
9
7
7192
r
o
le
is
im
p
lem
en
ted
in
HL
SP
L
in
s
id
e
th
e
AVI
SP
A
to
o
l.
C
AS+
lan
g
u
ag
e
is
also
u
s
ed
to
m
ak
e
th
e
f
o
r
m
u
latio
n
an
d
v
er
i
f
icatio
n
o
f
s
ec
u
r
ity
p
r
o
to
co
ls
s
im
p
le
an
d
s
tr
aig
h
tf
o
r
war
d
.
(
a)
(
b
)
Fig
u
r
e
2
.
Simu
latio
n
illu
s
tr
atin
g
h
o
w
ea
c
h
s
ess
io
n
an
d
e
n
v
ir
o
n
m
en
t r
o
le
is
im
p
lem
en
ted
i
n
HL
SP
L
in
s
id
e
th
e
AVI
SP
A
to
o
l (
a)
C
AS+
im
p
lem
en
tatio
n
o
f
th
e
p
r
o
p
o
s
ed
p
r
o
to
co
l a
n
d
(
b
)
AVI
SP
A
test
r
esu
lt in
AtSe
4
.
1
.
1
.
User
ro
le
T
h
e
u
s
er
r
o
le
d
escr
ib
es
h
o
w
th
e
u
s
er
in
ter
ac
ts
with
t
h
e
SH
en
v
ir
o
n
m
e
n
t
an
d
h
o
w
th
e
u
s
er
au
th
en
ticates a
n
d
co
n
n
ec
ts
th
e
h
o
m
e
d
ev
ices,
s
u
ch
as lig
h
ts
,
s
ec
u
r
ity
ca
m
er
as,
an
d
s
en
s
o
r
s
,
s
ec
u
r
ely
.
T
h
e
u
s
er
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2088
-
8
7
0
8
E
d
g
e
in
tern
et
o
f th
i
n
g
s
b
a
s
ed
s
ma
r
t h
o
me
p
a
s
s
w
o
r
d
les
s
a
u
th
en
tica
tio
n
(
Ma
h
a
Hela
l
)
7193
s
tar
ts
th
e
co
n
n
ec
tio
n
b
y
s
en
d
i
n
g
an
au
th
en
ticatio
n
r
eq
u
est
to
th
e
UAS,
p
r
o
v
id
in
g
u
s
er
d
et
ails
:
u
s
er
n
am
e,
u
s
er
id
en
tity
,
a
n
d
d
ev
ice
id
en
tity
.
T
h
e
UAS
r
ea
cts
to
th
e
r
e
q
u
est
in
itiated
b
y
th
e
u
s
er
to
v
er
if
y
h
is
/h
er
f
in
g
er
p
r
i
n
t
u
s
in
g
s
m
ar
tp
h
o
n
e
b
io
m
etr
ics.
T
h
e
u
s
er
s
en
d
s
th
e
b
io
m
etr
ics
v
er
if
icatio
n
to
g
et
a
s
ess
io
n
I
D
f
r
o
m
th
e
UAS
t
o
u
tili
ze
with
th
e
E
NS.
4
.
1
.
2
.
UAS
ro
le
T
h
e
UAS
is
r
esp
o
n
s
ib
le
f
o
r
cr
ea
tin
g
th
e
u
s
er
s
ess
io
n
I
D,
wh
ich
is
v
ital
to
th
e
u
s
er
b
ei
n
g
ab
le
to
co
n
tr
o
l
th
e
SH
d
ev
ices.
T
h
e
UAS
is
al
s
o
r
esp
o
n
s
ib
le
f
o
r
m
a
n
ag
in
g
a
u
th
en
ticatio
n
a
n
d
au
t
h
o
r
izatio
n
.
T
h
e
g
o
a
l
o
f
h
a
v
in
g
th
e
a
u
th
en
ticatio
n
s
er
v
er
o
n
s
ep
ar
ate
c
o
m
p
o
n
en
ts
is
to
s
ep
ar
ate
th
is
cr
itical
f
u
n
ctio
n
f
r
o
m
o
th
e
r
r
o
les,
wh
ich
will
g
r
a
n
t
a
b
et
ter
s
ec
u
r
ity
la
y
er
.
I
n
Ku
m
ar
an
d
C
h
o
u
h
an
[
2
8
]
a
u
th
en
tic
atio
n
s
ch
em
e,
th
e
au
th
en
ticatio
n
is
co
m
b
in
ed
with
th
e
E
NS,
s
o
th
e
E
NS
i
s
r
es
p
o
n
s
ib
le
f
o
r
b
o
t
h
co
n
tr
o
llin
g
an
d
m
o
n
ito
r
i
n
g
th
e
SHS
an
d
au
t
h
en
ticatin
g
th
e
u
s
er
s
.
Seg
r
eg
atin
g
th
e
two
r
o
le
s
in
to
d
if
f
er
en
t
co
m
p
o
n
en
ts
o
r
s
er
v
er
s
will
g
r
an
t
b
etter
s
ec
u
r
ity
.
I
n
th
e
ca
s
e
th
at
th
e
E
NS
is
co
m
p
r
o
m
is
ed
,
t
h
e
u
s
er
i
n
f
o
r
m
atio
n
will
r
e
m
a
in
s
af
e
in
th
e
UAS
an
d
in
th
e
ca
s
e
o
f
an
in
tr
u
d
er
co
m
p
r
o
m
is
in
g
th
e
UAS,
th
e
E
NS
ca
n
s
till
m
o
n
ito
r
an
d
co
n
tr
o
l
th
e
SHS
with
o
u
t
b
ein
g
af
f
ec
ted
b
y
an
in
tr
u
d
er
in
th
e
UAS.
4
.
1
.
3
.
E
NS
ro
le
T
h
e
r
o
le
o
f
th
e
E
NS
is
to
ac
t
as
a
s
tag
e
b
etwe
en
th
e
UA
S
an
d
th
e
SHS.
T
h
e
E
NS
co
n
tr
o
ls
an
d
m
o
n
ito
r
s
th
e
SHS
an
d
p
r
o
v
id
es
in
f
o
r
m
atio
n
to
th
e
SHS
ab
o
u
t
th
e
u
s
er
.
T
h
is
in
f
o
r
m
atio
n
in
clu
d
es
th
e
u
s
er
s
ess
io
n
I
D,
I
P a
d
d
r
ess
,
d
ev
ice
I
D,
an
d
wh
et
h
er
th
e
a
u
th
en
tic
atio
n
s
tatu
s
is
v
alid
o
r
in
v
alid
.
4
.
1
.
4
.
SH
S
ro
le
T
h
e
SHS
is
th
e
cl
o
s
est
lay
er
to
th
e
SH
d
ev
ices,
s
u
c
h
as
li
g
h
ts
,
telev
is
io
n
s
,
air
co
n
d
itio
n
in
g
u
n
its
,
p
r
in
ter
s
,
an
d
cl
o
s
ed
-
cir
cu
it
tel
ev
is
io
n
.
T
h
e
SHS
h
as
a
d
ir
ec
t c
o
n
n
ec
tio
n
t
o
th
e
s
m
ar
tp
h
o
n
e
u
s
er
.
On
ce
th
e
u
s
er
h
as
an
ac
tiv
e
an
d
v
alid
s
ess
i
o
n
I
D,
th
e
u
s
er
will
u
tili
ze
th
e
s
ess
io
n
I
D
to
co
m
m
u
n
icate
with
th
e
SHS
an
d
co
n
tr
o
l
an
d
au
to
m
ate
th
e
h
o
m
e
en
v
ir
o
n
m
e
n
t
r
em
o
tely
an
d
s
ec
u
r
ely
.
T
h
e
SHS
u
tili
ze
s
an
ex
ce
llen
t
au
th
en
ticatio
n
s
ch
em
e
an
d
v
er
y
co
n
f
i
n
ed
m
et
h
o
d
s
s
o
SH
u
s
er
s
ca
n
ac
ce
s
s
th
e
d
ev
ices
r
e
m
o
tely
an
d
s
ec
u
r
ely
an
d
th
en
u
tili
ze
th
e
h
o
m
e
s
er
v
er
co
m
p
o
n
en
ts
.
4
.
2
.
Securit
y
a
na
ly
s
is
o
f
t
he
pro
po
s
ed
a
uthent
ica
t
io
n schem
e
T
h
er
e
ar
e
v
ar
io
u
s
ty
p
es
o
f
at
tack
s
th
at
co
u
ld
co
m
p
r
o
m
is
e
th
e
s
ec
u
r
ity
o
f
SH
en
v
ir
o
n
m
en
ts
.
T
h
is
s
ec
tio
n
p
r
esen
ts
th
e
m
o
s
t
wid
ely
k
n
o
wn
ty
p
es
o
f
attac
k
s
.
I
t
d
is
cu
s
s
es
h
o
w
th
e
p
r
o
p
o
s
ed
au
th
en
ticatio
n
s
ch
em
e
co
u
ld
in
te
r
ac
t w
ith
d
if
f
er
en
t ty
p
es o
f
attac
k
s
.
4
.
2
.
1
.
M
a
n
-
in
-
t
he
-
m
idd
le
(
M
I
T
M
)
a
nd
denia
l
-
of
-
s
er
v
ice
(
Do
S)
a
t
t
a
c
k
s
An
in
tr
u
d
er
co
u
ld
b
e
b
etwe
en
an
y
two
co
m
p
o
n
en
ts
i
n
th
e
p
r
o
p
o
s
ed
au
th
e
n
ticatio
n
s
ch
em
e.
All
th
e
d
ata
tr
an
s
m
itted
b
etwe
en
th
e
p
r
o
p
o
s
ed
s
ch
em
e
ar
e
e
n
cr
y
p
te
d
.
T
h
e
o
n
ly
s
id
e
th
e
attac
k
er
ca
n
in
v
ad
e
is
if
th
e
in
tr
u
d
er
fin
d
s
th
e
s
ess
io
n
k
ey
.
I
n
th
at
ca
s
e,
th
e
attac
k
er
ca
n
u
s
e
th
e
s
es
s
io
n
k
ey
to
co
m
m
u
n
i
ca
te
with
th
e
SH
S
an
d
h
ac
k
t
h
e
SH
d
e
v
ices.
T
h
e
p
r
o
p
o
s
ed
a
u
th
en
ticatio
n
s
ch
em
e
s
o
lv
es
th
is
is
s
u
e
b
y
u
tili
zin
g
th
e
tim
estam
p
co
n
d
itio
n
,
w
h
ich
will
b
e
ca
lcu
lated
:
if
th
e
tim
estam
p
is
in
th
e
r
an
g
e,
th
at
m
ea
n
s
th
e
co
n
n
e
ctio
n
is
leg
itima
te;
o
th
er
wis
e,
th
e
co
n
n
ec
tio
n
is
d
r
o
p
p
ed
.
I
n
th
e
in
s
tan
ce
th
at
an
attac
k
e
r
f
o
r
g
es
in
f
o
r
m
atio
n
an
d
th
e
n
u
s
es
a
s
ec
r
et
k
ey
to
s
en
d
a
r
eq
u
est
to
th
e
h
o
m
e
s
er
v
er
,
t
h
e
in
tr
u
d
er
in
iti
ates
th
e
r
eq
u
est
an
d
s
en
d
s
it
to
th
e
SHS.
T
h
e
SHS
th
en
v
er
ifies
th
e
tim
estam
p
an
d
a
n
aly
ze
s
if
th
ey
ar
e
th
e
s
am
e,
in
wh
ich
ca
s
e
th
e
tr
an
s
ac
t
io
n
is
ac
ce
p
ted
; o
th
er
wis
e,
it
i
s
r
ejec
ted
.
On
ce
th
e
r
eq
u
est
r
ea
ch
es
th
e
SHS,
th
e
SHS
v
er
ifies
th
e
S
K,
wh
ich
is
th
e
s
es
s
io
n
k
ey
f
o
r
th
e
S
HS,
an
d
v
er
ifies
its
s
ess
io
n
k
ey
I
D.
A
tim
estam
p
co
n
d
itio
n
d
o
es
n
o
t
s
atis
f
y
th
e
u
p
p
er
lim
it
r
eq
u
ir
em
en
t
o
f
th
e
tim
estam
p
if
an
attac
k
er
co
m
p
r
o
m
is
es
th
e
v
e
r
ificatio
n
p
r
o
ce
d
u
r
e
,
as
s
h
o
w
n
in
t
h
e
f
o
llo
win
g
e
q
u
atio
n
:
[
(
2
−
1
)
≤
∆
]
wh
er
e
2
an
d
1
ar
e
th
e
first a
n
d
s
e
co
n
d
in
s
tan
ce
s
.
I
f
2
an
d
1
ar
e
in
th
e
ac
ce
p
t state,
b
o
th
ca
n
au
th
en
ticate
an
d
co
m
m
u
n
icate
m
ess
ag
es
w
ith
ea
ch
o
th
er
s
ec
u
r
ely
.
Similar
ly
,
in
a
Do
S
attac
k
,
if
th
e
atta
ck
er
s
tar
ts
s
en
d
in
g
an
en
o
r
m
o
u
s
n
u
m
b
er
o
f
r
eq
u
ests
th
at
d
o
n
o
t
m
atc
h
th
e
tim
estam
p
co
n
d
itio
n
,
th
e
s
y
s
tem
will
d
r
o
p
th
e
co
n
n
ec
tio
n
.
4
.
2
.
2
.
I
m
perso
na
t
io
n a
t
t
a
ck
s
I
m
p
er
s
o
n
atio
n
attac
k
s
ca
n
h
ap
p
en
in
th
r
ee
d
iffer
en
t
way
s
:
i
)
u
s
er
im
p
er
s
o
n
atio
n
;
ii
)
SHS
im
p
er
s
o
n
atio
n
;
an
d
iii
)
d
ev
ic
e
im
p
er
s
o
n
atio
n
.
Fo
r
a
u
s
er
im
p
er
s
o
n
atio
n
attac
k
,
th
e
in
tr
u
d
er
co
m
p
u
tes
th
e
id
en
titi
es,
s
u
ch
as
au
th
en
ticat
io
n
b
io
m
etr
ics,
u
s
er
I
D,
o
r
d
ev
ice
I
D,
a
n
d
ca
lcu
lates
th
e
cu
r
r
en
t
tim
estam
p
.
Ho
wev
er
,
with
th
e
p
r
o
p
o
s
ed
s
ch
em
e,
all
th
e
r
e
q
u
ests
will
f
ail
s
in
ce
th
e
id
en
titi
es
o
f
th
e
d
ev
ice
an
d
th
e
u
s
er
ar
e
co
n
tin
u
o
u
s
ly
u
p
d
ated
b
ec
au
s
e
o
f
th
e
tim
estam
p
co
n
d
itio
n
,
an
d
th
e
v
alu
e
o
f
th
e
id
e
n
tity
is
r
eg
en
er
ate
d
r
an
d
o
m
l
y
ev
er
y
tim
e
an
d
,
th
er
ef
o
r
e,
th
e
in
tr
u
d
e
r
ca
n
n
o
t d
ete
ct
it.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8
7
0
8
I
n
t J E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
14
,
No
.
6
,
Dec
em
b
e
r
20
24
:
7
1
8
6
-
7
1
9
7
7194
I
n
th
e
ca
s
e
o
f
a
n
SHS
im
p
e
r
s
o
n
atio
n
attac
k
,
th
e
attac
k
e
r
attem
p
ts
to
d
ec
ip
h
er
a
n
au
t
h
en
ticatio
n
m
ess
ag
e.
T
h
e
attac
k
er
also
ca
lcu
lates
th
e
tim
estam
p
a
n
d
m
a
k
es
th
is
r
eq
u
est
o
n
b
e
h
alf
o
f
t
h
e
SHS
to
th
e
u
s
er
en
d
as
th
e
f
o
llo
win
g
=
ℎ
(
)
|
|
,
=
ℎ
(
)
.
T
h
e
u
s
er
v
alid
ates
th
e
attac
k
er
’
s
au
th
en
ticatio
n
r
e
q
u
est.
Ho
wev
er
,
th
e
s
ec
r
et
k
ey
an
d
tim
estam
p
ar
e
n
o
t
c
o
m
p
u
ted
u
s
in
g
r
ea
l
k
ey
s
.
T
h
e
co
m
p
u
tatio
n
al
k
ey
s
an
d
s
ec
r
et
cr
ed
en
tials
o
f
th
e
SHS
ca
n
n
o
t
b
e
g
u
ess
ed
.
Fin
ally
,
th
e
attac
k
er
is
ca
p
ab
le
o
f
v
io
latin
g
s
ec
u
r
ity
; h
o
we
v
er
,
th
e
p
r
o
p
o
s
ed
s
ch
em
e
p
r
o
tects
co
n
f
id
e
n
tiality
ag
ain
s
t th
is
th
r
ea
t.
I
n
th
e
ca
s
e
o
f
a
d
ev
ice
im
p
e
r
s
o
n
atio
n
attac
k
,
th
e
in
tr
u
d
er
attem
p
ts
an
au
th
en
ticatio
n
m
ess
ag
e
b
y
=
ℎ
(
|
|
|
|
|
|
)
.
Su
b
s
eq
u
e
n
tly
,
t
h
e
in
tr
u
d
er
ca
lcu
lates
th
e
tim
estam
p
a
n
d
th
e
n
s
en
d
s
an
au
th
en
ticatio
n
r
eq
u
e
s
t
to
th
e
u
s
er
th
at
is
p
r
eten
d
i
n
g
to
h
av
e
o
r
ig
i
n
ated
f
r
o
m
th
e
SHS.
T
h
e
u
s
er
will
v
er
if
y
th
e
a
u
th
en
ticatio
n
r
e
q
u
est
as
th
e
f
o
llo
win
g
ℎ
(
|
|
|
|
|
|
)
.
Ho
wev
er
,
th
e
tim
estam
p
an
d
s
ec
r
et
k
ey
ar
e
n
o
t
co
m
p
u
ted
u
s
in
g
th
e
ac
tu
al
k
ey
s
.
I
t
is
im
p
o
s
s
ib
le
to
g
u
ess
th
e
s
e
s
s
io
n
k
ey
an
d
,
th
er
e
f
o
r
e,
ev
en
i
f
th
e
atta
ck
er
b
r
ea
c
h
es th
e
s
y
s
tem
,
th
e
p
r
o
p
o
s
ed
s
ch
em
e
will st
ill b
e
m
ain
tain
ed
.
4
.
2
.
3
.
Ano
ny
m
it
y
a
nd
un
t
ra
ce
a
ble a
t
t
a
c
k
s
An
o
n
y
m
ity
a
n
d
u
n
t
r
ac
ea
b
le
at
tack
s
o
cc
u
r
wh
en
an
attac
k
er
p
ass
iv
ely
lis
ten
s
to
th
e
n
etwo
r
k
,
with
o
u
t
an
y
i
n
ter
ac
tio
n
.
Ass
u
m
in
g
t
h
a
t
th
e
attac
k
e
r
s
n
iffs
tr
affic
b
et
wee
n
th
e
u
s
er
an
d
th
e
UAS,
t
h
e
attac
k
er
will
n
o
t
b
e
ab
le
to
r
ea
d
th
e
m
ess
ag
es
s
in
ce
th
e
tr
affic
is
en
cr
y
p
ted
b
y
th
e
u
s
er
id
en
tity
.
A
r
an
d
o
m
n
u
m
b
er
is
g
en
er
ate
d
ev
er
y
tim
e
,
wh
ich
will
m
ak
e
d
ec
r
y
p
tin
g
th
e
m
ess
ag
es
im
p
o
s
s
ib
le
f
o
r
a
n
in
t
r
u
d
er
.
T
h
er
e
f
o
r
e,
if
a
n
attac
k
er
b
r
ea
ch
es
th
e
n
etwo
r
k
,
th
e
p
r
o
p
o
s
ed
s
ch
em
e
will
p
r
o
tect
th
e
p
r
iv
ac
y
o
f
th
e
u
s
er
’
s
in
f
o
r
m
a
tio
n
an
d
m
ess
ag
es.
I
n
th
e
in
s
tan
ce
th
at
an
in
tr
u
d
e
r
o
b
s
er
v
es
an
d
ea
v
esd
r
o
p
s
o
n
th
e
co
m
m
u
n
icatio
n
s
b
etwe
en
t
h
e
tr
u
s
ted
u
s
er
an
d
th
e
SHS,
all
m
es
s
ag
es
ar
e
co
m
p
u
ted
u
s
in
g
a
s
ec
r
et
p
s
eu
d
o
-
id
en
tity
an
d
a
r
a
n
d
o
m
n
u
m
b
e
r
g
en
er
ato
r
,
m
ak
in
g
ea
v
esd
r
o
p
p
i
n
g
im
p
o
s
s
ib
le.
U
s
in
g
a
tim
estam
p
with
ea
c
h
r
eq
u
ested
p
ac
k
et
will
en
ab
le
s
u
ch
ass
au
lts
to
b
e
r
esis
ted
an
d
r
etain
an
o
n
y
m
ity
an
d
ad
d
r
ess
es th
e
f
ea
r
o
f
a
n
at
tack
b
ein
g
u
n
tr
ac
ea
b
le
.
4
.
2
.
4
.
Dev
ice
co
m
pro
m
is
e
a
t
t
a
ck
s
An
attac
k
er
m
ay
also
co
n
d
u
ct
d
ev
ice
co
m
p
r
o
m
is
e
attac
k
s
b
y
ca
p
tu
r
i
n
g
u
s
er
d
ev
ices
an
d
th
e
n
attem
p
tin
g
to
s
teal
th
eir
s
ec
r
et
p
ar
am
eter
s
an
d
u
n
iq
u
e
I
I
D
b
i
ts
.
T
h
e
attac
k
er
th
e
n
tr
a
n
s
m
its
a
lo
g
in
r
eq
u
est
t
o
th
e
SHS
(
I
Din
tr
u
d
er
,
I
Dd
ivice
,
I
Du
s
er
,
an
d
b
io
m
etr
ics).
T
h
e
SHS
v
alid
ates
th
e
r
eq
u
est
an
d
co
m
p
u
tes
th
e
v
ar
iab
le
f
r
o
m
th
e
I
Ds.
Ho
wev
er
,
th
e
SHS will r
ejec
t a
n
u
n
au
th
o
r
ized
r
e
q
u
est s
in
ce
th
e
attac
k
er
d
id
n
o
t u
s
e
th
e
tr
u
s
ted
u
s
er
an
d
d
e
v
ice
s
ec
r
et
id
en
titi
es,
wh
ich
o
n
l
y
th
e
t
r
u
s
ted
u
s
er
k
n
o
ws.
E
x
is
tin
g
tech
n
iq
u
es
d
o
n
o
t
o
f
f
er
s
ec
u
r
ity
ag
ain
s
t
d
ev
ice
c
o
m
p
r
o
m
is
e
attac
k
s
;
h
o
wev
er
,
t
h
e
p
r
o
p
o
s
ed
a
u
th
en
ticatio
n
s
ch
em
e
ca
n
p
r
o
v
id
e
s
ec
u
r
ity
ag
ain
s
t
th
is
ty
p
e
o
f
attac
k
s
u
ch
th
at
an
attac
k
er
ca
n
n
o
t
cir
cu
m
v
en
t
th
e
au
th
en
tic
atio
n
p
r
o
ce
s
s
.
T
h
e
ad
v
an
tag
es
o
f
t
h
e
p
r
o
p
o
s
ed
au
th
en
ticatio
n
s
ch
e
m
e,
esp
ec
ially
in
d
e
v
ice
co
m
p
r
o
m
is
e
attac
k
s
,
co
m
e
f
r
o
m
h
av
in
g
s
ev
e
r
al
lay
er
s
o
f
a
u
th
e
n
ticatio
n
an
d
m
u
ltip
le
id
en
titi
es.
4
.
2
.
5
.
Repla
y
a
t
t
a
c
k
s
An
attac
k
er
m
ay
in
ter
ce
p
t
all
co
m
m
u
n
icatio
n
,
ac
q
u
ir
e
s
ec
r
et
p
ar
am
eter
s
,
an
d
th
e
n
lau
n
c
h
a
r
ep
lay
attac
k
b
y
tr
a
n
s
f
er
r
in
g
all
th
e
i
d
en
titi
es
s
to
r
ed
in
th
e
u
s
er
’
s
s
m
ar
tp
h
o
n
es,
s
u
ch
as
5
6
-
b
it
-
I
I
D
an
d
8
-
b
it
-
I
I
D
at
tim
estam
p
T
at
tack
er
,
to
th
e
S
HS.
A
r
ep
lay
attac
k
ca
n
n
o
t
b
e
attem
p
ted
d
u
e
to
t
h
e
v
er
ificatio
n
o
f
th
e
m
ess
ag
e
tim
estam
p
an
d
th
e
tim
e
i
n
ter
v
al
[
(
2
−
1
)
≤
∆
]
,
wh
er
e
T
is
th
e
m
u
tu
ally
ag
r
ee
d
-
u
p
o
n
u
p
p
er
lim
it
b
etwe
en
th
e
tr
u
s
ted
en
titi
es.
T
h
is
tim
e
-
s
en
s
i
tiv
e
co
n
d
itio
n
ap
p
lies
to
all
m
es
s
ag
es
r
e
ce
iv
ed
d
u
r
in
g
th
e
co
n
v
er
s
atio
n
.
Fin
ally
,
th
e
SHS
co
m
p
u
tes
a
tim
e
-
b
o
u
n
d
to
k
en
,
r
ejec
ts
th
e
attac
k
er
’
s
to
k
e
n
,
an
d
d
e
n
ies
s
ess
io
n
k
ey
ac
ce
s
s
.
T
h
e
b
e
n
efits
o
f
h
a
v
in
g
a
m
u
t
u
ally
ag
r
ee
d
tim
e
a
r
e
cr
u
cial
in
th
e
p
r
o
p
o
s
ed
au
t
h
en
ticatio
n
s
ch
em
e,
s
in
ce
it m
ak
es th
e
au
th
en
ticati
o
n
u
n
i
q
u
e
a
n
d
s
ec
u
r
e
a
n
d
p
r
o
v
id
es a
d
ef
en
s
e
ag
ain
s
t m
u
ltip
le
attac
k
s
.
4
.
3
.
Ana
ly
s
is
o
f
t
he
perf
o
rm
a
nce
o
f
t
he
pro
po
s
ed
a
uthent
ica
t
io
n schem
e
Similar
ly
to
th
e
s
ec
u
r
ity
a
n
a
ly
s
is
ab
o
v
e,
th
is
s
ec
tio
n
d
is
c
u
s
s
es
th
e
p
er
f
o
r
m
a
n
ce
an
aly
s
is
o
f
th
e
p
r
o
p
o
s
ed
au
th
e
n
ticatio
n
s
ch
e
m
e.
T
h
is
will
h
elp
in
d
eter
m
i
n
in
g
th
e
f
ea
s
ib
ilit
y
o
f
th
e
p
r
o
p
o
s
ed
s
ch
em
e
th
r
o
u
g
h
a
f
u
n
ctio
n
al
c
o
m
p
a
r
is
o
n
an
d
b
y
co
n
s
id
er
in
g
th
e
c
o
m
m
u
n
icatio
n
co
s
ts
.
Fu
r
th
er
d
etails ar
e
d
is
cu
s
s
ed
b
elo
w.
4
.
3
.
1
.
F
un
ct
io
na
l c
o
m
pa
riso
n
T
h
e
s
ec
u
r
ity
f
u
n
ctio
n
ality
o
f
th
e
p
r
o
p
o
s
ed
s
ch
em
e
was
c
o
m
p
ar
ed
to
K
u
m
ar
a
n
d
C
h
o
u
h
an
[
2
8
]
au
th
en
ticatio
n
s
ch
em
e
.
T
h
e
p
r
o
p
o
s
ed
a
u
th
en
ticatio
n
s
ch
em
e
u
tili
ze
s
th
e
b
en
ef
its
o
f
th
e
b
io
m
et
r
ics
au
th
en
ticatio
n
in
a
s
m
ar
tp
h
o
n
e,
wh
ich
p
r
o
v
id
es
co
n
v
en
ie
n
t
an
d
e
n
h
an
ce
d
s
ec
u
r
ity
f
o
r
th
e
SH
u
s
er
.
T
h
e
co
n
v
en
ie
n
ce
o
f
t
h
e
p
r
o
p
o
s
ed
au
th
e
n
ticatio
n
s
ch
em
e
an
d
it
s
s
ec
u
r
ity
ar
e
a
r
esu
lt
o
f
t
h
e
s
eg
r
eg
atio
n
o
f
th
e
au
th
en
ticatio
n
s
er
v
e
r
.
B
y
p
la
cin
g
th
e
UAS
b
etwe
en
th
e
u
s
er
an
d
th
e
E
NS,
th
is
s
tep
p
lay
s
a
v
ital
r
o
le
in
s
eg
r
eg
atin
g
th
e
c
o
n
tr
o
l
o
f
th
e
m
o
n
ito
r
in
g
f
r
o
m
th
e
a
u
th
en
tic
atio
n
.
T
h
e
p
r
o
p
o
s
ed
s
ch
em
e
allo
ws
f
o
r
m
u
ltip
le
lay
e
r
s
o
f
c
o
n
tr
o
l
th
at
p
r
o
v
id
e
d
ef
e
n
s
e
in
d
e
p
th
.
Af
te
r
s
eg
r
eg
atin
g
t
h
e
a
u
th
en
ticatio
n
s
er
v
ice
f
r
o
m
th
e
co
n
tr
o
l
a
n
d
m
o
n
ito
r
in
g
s
er
v
ice,
th
e
s
ch
em
e
o
b
tain
s
s
tr
o
n
g
in
-
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2088
-
8
7
0
8
E
d
g
e
in
tern
et
o
f th
i
n
g
s
b
a
s
ed
s
ma
r
t h
o
me
p
a
s
s
w
o
r
d
les
s
a
u
th
en
tica
tio
n
(
Ma
h
a
Hela
l
)
7195
d
ep
th
s
ec
u
r
ity
b
y
c
h
an
g
in
g
th
e
ar
c
h
itectu
r
e.
Ho
wev
er
,
ad
d
in
g
a
n
au
t
h
en
ticatio
n
s
er
v
er
i
n
a
d
iffer
en
t
co
m
p
o
n
en
t
will
r
esu
lt
in
h
ig
h
er
co
s
ts
,
as
m
o
r
e
r
eso
u
r
ce
s
ar
e
n
ee
d
ed
.
Fu
r
th
er
m
o
r
e,
th
is
will
r
esu
lt
in
h
ig
h
er
laten
cy
,
m
ain
ly
if
th
e
s
ess
io
n
is
n
o
t
g
en
er
ated
,
b
ec
au
s
e
th
e
u
s
er
will
wai
t
f
o
r
th
e
s
es
s
io
n
cr
ea
tio
n
an
d
to
b
e
g
r
an
ted
ac
ce
s
s
in
th
e
E
NS a
n
d
o
n
th
e
u
s
er
s
id
e.
4
.
3
.
2
.
Co
mm
un
ica
t
io
n c
o
s
t
T
h
e
p
r
o
p
o
s
ed
s
ch
em
e
ass
u
m
es
th
at
s
m
ar
tp
h
o
n
e
-
b
ased
id
e
n
titi
es
ar
e
a
f
ac
to
r
,
wh
ich
in
clu
d
es
u
s
er
b
io
m
etr
ics
an
d
u
n
iq
u
e
id
en
tif
icatio
n
b
its
f
o
r
b
o
th
th
e
u
s
er
an
d
th
e
d
ev
ice.
Sm
a
r
tp
h
o
n
e
I
Ds
ar
e
in
clu
d
ed
in
ea
ch
p
ac
k
et
with
o
u
t
in
cr
ea
s
i
n
g
its
s
ize
o
r
th
e
o
v
er
h
ea
d
.
T
h
e
p
r
o
p
o
s
ed
s
ch
em
e
u
tili
ze
s
th
e
p
ar
am
eter
s
as
ex
is
tin
g
s
ch
em
es
to
ca
lcu
late
th
e
co
m
m
u
n
icatio
n
c
o
s
t
o
f
th
e
d
esig
n
ed
p
r
o
to
co
l.
Fo
r
e
x
am
p
le,
th
e
g
atew
ay
id
en
tity
is
3
2
b
its
,
th
e
tim
estam
p
is
3
2
b
its
,
th
e
h
ash
is
3
2
b
its
,
an
d
th
e
s
ess
io
n
k
ey
(
SK)
is
3
2
b
its
.
A
n
o
n
ce
r
an
d
XOR
o
p
er
atio
n
also
tak
e
u
p
3
2
b
its
an
d
th
e
len
g
th
o
f
th
e
s
h
ar
ed
k
ey
s
is
1
6
0
b
its
.
I
n
th
e
p
r
o
p
o
s
ed
s
ch
em
e,
th
r
ee
m
ess
ag
es
ar
e
u
s
ed
f
o
r
au
th
en
ticatio
n
an
d
lo
g
in
p
u
r
p
o
s
e
s
co
m
p
ar
ed
to
f
iv
e
m
ess
ag
es
in
s
im
ilar
s
ch
em
es.
T
h
is
r
ed
u
ce
s
th
e
co
m
m
u
n
icati
o
n
co
s
t to
9
5
9
b
its
,
wh
ich
is
s
ig
n
if
ican
tly
lo
wer
th
an
th
at
o
f
p
r
ev
io
u
s
m
et
h
o
d
s
.
4
.
4
.
Su
mm
a
r
y
As
p
r
ev
io
u
s
ly
m
en
tio
n
ed
,
th
e
aim
o
f
th
is
r
esear
ch
is
to
in
c
r
ea
s
e
th
e
s
ec
u
r
ity
o
f
ed
g
e
I
o
T
-
b
ased
SH
n
etwo
r
k
s
wh
ile
r
ed
u
cin
g
c
o
m
p
lex
ity
to
ac
h
iev
e
a
h
ig
h
e
r
u
s
ab
ilit
y
lev
el.
I
t
ca
n
clea
r
ly
b
e
s
ee
n
in
th
e
an
aly
s
is
o
f
th
e
s
ec
u
r
ity
co
m
p
ar
is
o
n
th
at
th
e
p
r
o
p
o
s
ed
a
u
th
en
ticatio
n
s
ch
em
e
ca
n
h
an
d
le
d
if
f
e
r
en
t
ty
p
es
o
f
attac
k
s
.
I
t
also
p
r
o
v
ed
its
a
b
ilit
y
to
p
r
o
v
id
e
a
h
ig
h
lev
el
o
f
p
r
o
tectio
n
to
ed
g
e
I
o
T
-
b
ased
SH
n
etwo
r
k
s
.
W
ith
r
eg
ar
d
t
o
u
s
ab
ilit
y
an
d
th
e
co
s
t
o
f
im
p
lem
en
tin
g
th
e
p
r
o
p
o
s
ed
s
ch
em
e,
it
was
ev
id
en
t
th
at
th
e
p
r
o
p
o
s
ed
s
ch
em
e
is
ca
p
ab
le
o
f
p
r
o
v
id
in
g
h
ig
h
er
s
e
cu
r
ity
f
u
n
ctio
n
ality
at
a
r
ea
s
o
n
ab
le
co
s
t.
T
h
e
s
ch
em
e
also
a
ch
iev
ed
a
r
ed
u
ctio
n
in
co
m
m
u
n
icatio
n
co
s
ts
co
m
p
ar
ed
to
p
r
e
v
io
u
s
s
ch
em
es,
wh
ich
,
in
tu
r
n
,
m
ak
es
it
m
o
r
e
f
e
asib
le
in
r
ea
l
-
wo
r
ld
s
ce
n
ar
io
s
.
5.
CO
NCLU
SI
O
N
T
h
e
p
r
im
ar
y
o
b
jectiv
e
o
f
th
is
r
esear
ch
is
to
o
f
f
er
a
m
eth
o
d
f
o
r
th
e
p
r
o
tectio
n
o
f
a
n
et
wo
r
k
f
r
o
m
attac
k
er
s
an
d
th
e
p
r
o
v
is
io
n
o
f
s
af
e
ac
ce
s
s
to
SH
s
er
v
ic
es
wh
ile
m
ain
tain
in
g
a
v
er
y
co
n
v
en
ien
t
u
s
er
ex
p
er
ien
ce
.
I
n
th
e
p
r
o
p
o
s
ed
s
ch
em
e,
a
s
m
ar
tp
h
o
n
e
o
ffer
s
b
io
m
etr
ic
au
th
en
ticatio
n
to
s
m
ar
t
d
ev
ices/ap
p
lian
ce
s
u
s
in
g
th
eir
u
n
iq
u
e
I
D
b
its
,
allo
win
g
th
e
s
er
v
er
to
id
e
n
tify
th
em
with
o
u
t
r
esu
ltin
g
in
ex
tr
a
ex
p
en
s
e.
Mo
r
e
o
v
er
,
th
e
s
ess
io
n
k
ey
co
n
s
tr
u
ctio
n
o
f
s
ec
r
et
k
e
y
s
an
d
id
en
titi
es
in
c
r
ea
s
es
th
e
n
etwo
r
k
’
s
r
esis
tan
ce
to
v
ar
io
u
s
t
h
r
ea
ts
.
T
h
e
o
v
er
h
ea
d
co
s
ts
o
f
th
is
s
ch
em
e
ar
e
id
en
tical
to
th
o
s
e
o
f
t
h
e
co
n
v
en
tio
n
al
I
Pv
6
.
T
h
e
AVI
SP
A
-
b
ased
s
ec
u
r
ity
an
aly
s
is
g
iv
en
in
t
h
is
s
ch
em
e
en
s
u
r
es th
at
th
is
s
ch
em
e
is
s
af
e
an
d
ac
h
iev
a
b
le.
T
h
e
co
llected
fin
d
in
g
s
s
u
g
g
es
t
th
at
th
e
p
r
o
p
o
s
ed
au
th
e
n
tica
tio
n
s
ch
em
e
o
f
f
er
s
g
r
ea
ter
s
ec
u
r
ity
th
an
th
e
s
ch
em
e
p
r
o
v
id
ed
b
y
ea
r
l
ier
s
ch
o
lar
s
.
T
h
e
s
u
g
g
ested
s
ch
em
e
in
cr
ea
s
es
th
e
s
ec
u
r
ity
an
d
en
h
a
n
ce
s
th
e
u
s
ab
ilit
y
o
f
th
e
h
o
m
e
au
to
m
a
tio
n
b
u
s
in
ess
.
I
t
allo
ws
h
o
m
e
u
s
er
s
to
u
s
e
h
o
m
e
au
to
m
ati
o
n
s
er
v
ices
f
r
o
m
a
r
em
o
te
p
lace
s
ec
u
r
ely
,
with
o
u
t
in
ter
r
u
p
tio
n
f
r
o
m
in
tr
u
d
er
s
.
I
n
ad
d
itio
n
,
th
e
s
tr
en
g
th
o
f
th
e
p
r
o
p
o
s
ed
s
ch
em
e
is
d
er
iv
ed
f
r
o
m
th
e
s
ep
ar
atio
n
o
f
th
e
au
th
en
ticatio
n
s
er
v
e
r
co
m
p
o
n
e
n
ts
.
T
h
is
p
r
o
v
id
es
h
ig
h
er
s
ec
u
r
ity
th
r
o
u
g
h
th
e
d
esig
n
o
f
th
e
SH
en
v
ir
o
n
m
en
t,
h
en
ce
p
r
e
v
en
tin
g
s
ev
er
al
ty
p
es
o
f
attac
k
s
an
d
en
h
an
cin
g
t
h
e
s
ec
u
r
ity
lay
er
s
.
T
h
r
ee
p
at
h
s
o
f
r
esear
ch
c
o
u
ld
b
e
co
n
d
u
cte
d
in
f
u
tu
r
e
wo
r
k
.
T
h
e
first
p
ath
is
to
f
o
cu
s
o
n
en
h
an
cin
g
th
e
cu
r
r
en
t
au
th
e
n
ticatio
n
s
ch
em
e
b
y
in
cr
ea
s
in
g
t
h
e
s
ec
u
r
ity
an
d
r
e
d
u
cin
g
t
h
e
s
tep
s
r
eq
u
ir
ed
f
o
r
au
th
en
ticatio
n
to
m
ak
e
it
f
aste
r
an
d
m
o
r
e
c
o
n
v
e
n
ien
t.
T
h
e
s
ec
o
n
d
p
ath
is
to
s
tar
t
im
p
lem
en
tin
g
th
e
s
ch
em
e
in
a
r
ea
l
en
v
ir
o
n
m
e
n
t
to
d
em
o
n
s
tr
ate
th
e
r
esu
lts
an
d
m
ea
s
u
r
e
wh
eth
er
th
e
u
s
er
ex
p
er
ien
c
e
is
co
n
v
en
ien
t
o
r
co
m
p
lex
.
I
t
w
o
u
ld
also
b
e
i
n
s
tr
u
ctiv
e
to
attem
p
t
all
th
e
ex
p
ec
ted
attac
k
s
a
n
d
s
ee
th
e
ef
f
icien
cy
o
f
th
e
p
r
o
p
o
s
ed
s
ch
em
e
in
p
r
ac
tice.
Fin
ally
,
th
e
th
ir
d
p
ath
is
to
a
p
p
ly
th
e
p
r
o
p
o
s
ed
au
th
e
n
ticatio
n
s
ch
em
e
in
a
n
o
th
er
s
ec
to
r
,
s
u
ch
as h
ea
lth
ca
r
e,
w
h
ich
u
tili
ze
s
s
im
ilar
r
o
les an
d
p
e
r
s
o
n
a.
RE
F
E
R
E
NC
E
S
[
1
]
N
.
A
l
h
i
n
d
a
w
i
,
“
I
o
T
b
a
se
d
t
e
c
h
n
i
q
u
e
f
o
r
n
e
t
w
o
r
k
p
a
c
k
e
t
a
n
a
l
y
z
e
r
,
”
T
h
e
I
n
t
e
r
n
a
t
i
o
n
a
l
Ara
b
J
o
u
r
n
a
l
o
f
I
n
f
o
rm
a
t
i
o
n
T
e
c
h
n
o
l
o
g
y
,
v
o
l
.
2
0
,
n
o
.
4
,
p
p
.
6
7
8
–
6
8
5
,
2
0
2
3
,
d
o
i
:
1
0
.
3
4
0
2
8
/
i
a
j
i
t
/
2
0
/
4
/
1
4
.
[
2
]
“
I
n
t
e
r
n
e
t
o
f
t
h
i
n
g
s
(
I
o
T
)
,
”
G
a
rt
n
e
r
,
2
0
1
2
.
h
t
t
p
s
:
/
/
w
w
w
.
g
a
r
t
n
e
r
.
c
o
m/
e
n
/
i
n
f
o
r
ma
t
i
o
n
-
t
e
c
h
n
o
l
o
g
y
/
g
l
o
ss
a
r
y
/
i
n
t
e
r
n
e
t
-
of
-
t
h
i
n
g
s
(a
c
c
e
s
se
d
M
a
y
1
,
2
0
2
4
).
[
3
]
“
W
h
a
t
i
s
t
h
e
i
n
t
e
r
n
e
t
o
f
t
h
i
n
g
s (I
o
T)
?
,
”
I
BM
,
2
0
2
4
.
h
t
t
p
s:
/
/
w
w
w
.
i
b
m
.
c
o
m/
t
o
p
i
c
s/
i
n
t
e
r
n
e
t
-
of
-
t
h
i
n
g
s
(a
c
c
e
ss
e
d
M
a
y
1
,
2
0
2
4
).
[
4
]
C
.
M
a
c
g
i
l
l
i
v
r
a
y
,
S
.
R
a
u
,
N
.
T
u
r
n
e
r
,
a
n
d
A
.
W
r
i
g
h
t
,
“
O
v
e
r
c
o
m
i
n
g
c
h
a
l
l
e
n
g
e
s:
b
e
st
p
r
a
c
t
i
c
e
s
f
o
r
I
o
T
i
m
p
l
e
m
e
n
t
a
t
i
o
n
s
,”
W
h
i
t
e
Pa
p
e
r
,
IDC
.
2
0
1
6
,
A
c
c
e
sse
d
:
M
a
y
1
,
2
0
2
4
.
[
O
n
l
i
n
e
]
.
A
v
a
i
l
a
b
l
e
:
h
t
t
p
s
:
/
/
d
o
w
n
l
o
a
d
.
n
i
.
c
o
m/
e
v
a
l
u
a
t
i
o
n
/
i
o
t
/
I
D
C
_
W
h
i
t
e
p
a
p
e
r
.
p
d
f
[
5
]
F
.
F
i
r
o
u
z
i
,
B
.
F
a
r
a
h
a
n
i
,
M
.
W
e
i
n
b
e
r
g
e
r
,
G
.
D
e
P
a
c
e
,
a
n
d
F
.
S
.
A
l
i
e
e
,
“
I
o
T
f
u
n
d
a
me
n
t
a
l
s
:
d
e
f
i
n
i
t
i
o
n
s,
a
r
c
h
i
t
e
c
t
u
r
e
s,
c
h
a
l
l
e
n
g
e
s,
a
n
d
p
r
o
m
i
ses
,
”
i
n
I
n
t
e
l
l
i
g
e
n
t
I
n
t
e
rn
e
t
o
f
T
h
i
n
g
s
,
C
h
a
m:
S
p
r
i
n
g
e
r
I
n
t
e
r
n
a
t
i
o
n
a
l
P
u
b
l
i
s
h
i
n
g
,
2
0
2
0
,
p
p
.
3
–
5
0
.
[
6
]
C
.
B
e
n
i
t
e
z
,
“
Th
e
u
l
t
i
ma
t
e
l
i
s
t
o
f
i
n
t
e
r
n
e
t
o
f
t
h
i
n
g
s
st
a
t
i
st
i
c
s
f
o
r
2
0
2
4
,
”
F
i
n
d
s
t
a
c
k
b
y
S
o
h
o
Me
d
i
a
L
t
d
.
h
t
t
p
s
:
/
/
f
i
n
d
s
t
a
c
k
.
c
o
m/
i
n
t
e
r
n
e
t
-
of
-
t
h
i
n
g
s
-
st
a
t
i
st
i
c
s
/
(
a
c
c
e
sse
d
M
a
r
.
2
1
,
2
0
2
4
).
Evaluation Warning : The document was created with Spire.PDF for Python.