T
E
L
KO
M
N
I
KA
T
e
lec
om
m
u
n
icat
ion
,
Com
p
u
t
i
n
g,
E
lec
t
r
on
ics
an
d
Cont
r
ol
Vol.
1
8
,
No.
5
,
Oc
tober
2020
,
pp
.
2543
~
2548
I
S
S
N:
1693
-
6930,
a
c
c
r
e
dit
e
d
F
ir
s
t
G
r
a
de
by
Ke
me
nr
is
tekdik
ti
,
De
c
r
e
e
No:
21/E
/KP
T
/2018
DO
I
:
10.
12928/
T
E
L
KO
M
NI
KA
.
v1
8
i
5
.
15276
2543
Jou
r
n
al
h
omepage
:
ht
tp:
//
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nal.
uad
.
ac
.
id/
index
.
php/T
E
L
K
OM
N
I
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A
A
n
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w
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go
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ti
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R
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ived
J
a
n
11,
2020
R
e
vis
e
d
M
a
r
18,
2020
Ac
c
e
pted
M
a
y
8,
2020
IT
s
y
s
t
em
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d
d
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s
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re,
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l
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rce
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p
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t
ect
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al
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d
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i
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o
f
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et
w
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mp
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afe
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h
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d
a
t
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s
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e
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b
y
o
n
e
p
art
y
as
v
al
i
d
(
o
r
u
n
al
t
ered
)
b
y
t
h
e
o
t
h
er
p
art
y
.
In
o
u
r
s
t
u
d
y
,
w
e
s
u
g
g
e
s
t
n
ew
o
n
e
-
w
ay
d
efrag
me
n
t
a
t
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o
n
al
g
o
r
i
t
h
m
t
o
i
mp
l
eme
n
t
mes
s
ag
e
au
t
h
e
n
t
i
cat
i
o
n
an
d
i
n
t
eg
ra
t
i
o
n
i
n
p
ro
g
ram
ex
ec
u
t
i
o
n
.
T
h
e
s
e
s
o
f
t
w
are
a
p
p
l
i
cat
i
o
n
s
are
read
i
l
y
av
ai
l
ab
l
e
an
d
freel
y
av
ai
l
ab
l
e
b
eca
u
s
e
mo
s
t
o
f
t
h
e
h
as
h
fu
n
c
t
i
o
n
s
are
fas
t
er
t
h
a
n
t
h
e
i
r
ex
i
s
t
i
n
g
rad
i
o
ac
t
i
v
e
b
l
o
c
k
s
.
K
e
y
w
o
r
d
s
:
Au
thentica
ti
on
int
e
gr
it
y
Ha
s
h
f
unc
ti
ons
Va
li
da
ti
on
Th
i
s
i
s
a
n
o
p
en
a
c
ces
s
a
r
t
i
c
l
e
u
n
d
e
r
t
h
e
CC
B
Y
-
SA
l
i
ce
n
s
e
.
C
or
r
e
s
pon
din
g
A
u
th
or
:
Ha
ider
R
a
s
he
e
d
Abduls
ha
he
e
d
B
a
ghda
d
C
oll
e
ge
of
E
c
onomi
c
S
c
ienc
e
s
Unive
r
s
it
y,
B
a
ghda
d,
I
r
a
q
.
E
mail:
ha
ider
252004@ya
hoo
.
c
om
1.
I
NT
RODU
C
T
I
ON
Authe
nti
c
a
ti
on
a
nd
mes
s
a
ge
int
e
gr
it
y
a
r
e
done
by
s
e
ve
r
a
l
methods
.
P
a
r
a
ll
e
l
e
nc
r
ypti
on
mec
ha
nis
ms
c
a
n
be
us
e
d
but
ha
ve
their
dis
a
dva
ntage
s
.
T
s
udik
h
ighl
ight
e
d
the
[
1
]
d
is
a
dva
ntage
s
s
uc
h
a
s
s
pe
e
d,
c
os
t
f
a
c
tor
,
opti
mi
z
a
ti
on
of
da
ta
s
ize
s
a
nd
s
o
on.
T
he
s
e
meth
ods
c
ombi
ne
the
f
unc
ti
ons
of
c
onf
ident
ialit
y
a
nd
a
uthentica
ti
on.
B
ut
ther
e
a
r
e
s
c
e
na
r
ios
whe
r
e
the
c
ompl
e
te
mes
s
a
ge
is
not
r
e
quir
e
d.
S
uc
h
a
s
a
ppl
ica
ti
ons
,
mes
s
a
ge
s
s
tor
ing
c
onf
idential
is
not
a
c
onc
e
r
n,
bu
t
a
uthentica
ti
on
is
im
por
tant
.
F
o
r
e
xa
mpl
e
,
in
S
N
M
P
it
is
us
ua
ll
y
im
por
tant
f
or
a
mana
ge
d
s
ys
tem
to
a
uthentica
te
incoming
S
NM
P
c
omm
a
nds
(
s
uc
h
a
s
a
lt
e
r
a
ti
on
pa
r
a
mete
r
s
in
the
mana
ge
ment
s
ys
tem)
but
hidi
ng
S
NM
P
tr
a
f
f
ic
is
not
r
e
quir
e
d
.
To
im
pleme
nt
mes
s
a
ge
a
uthentica
ti
on,
a
lt
e
r
na
ti
ve
tec
hniques
(
e
xc
e
pt
th
a
t
mentioned
in
the
las
t
pa
r
a
gr
a
ph)
a
r
e
f
r
a
gmenta
ti
on
f
unc
ti
ons
or
M
AC
.
M
a
c
s
ys
tem
make
s
long
s
e
r
ial
z
e
r
os
s
uc
h
a
s
DE
S
.
I
de
a
of
c
r
e
a
ti
ng
M
AC
de
vice
s
is
s
tar
ted
s
pr
e
a
ding
f
r
om
c
r
yptogr
a
phic
f
r
a
gmenta
ti
on
f
unc
ti
ons
[
2
]
.
S
e
e
F
igu
r
e
1
.
2.
CR
YP
T
OG
RA
P
HY
T
he
e
nc
r
ypti
on
c
ould
pr
ovide
many
r
oles
in
the
a
uthentica
ti
on.
T
he
a
uthentica
ti
on
c
a
pa
bil
it
ies
us
e
of
c
omm
on
c
r
yptogr
a
phic
ke
ys
,
whic
h
a
r
e
only
o
wne
d
by
li
c
e
ns
e
d
e
nti
ti
e
s
.
T
he
e
nc
oding
plays
a
n
i
mpor
tant
r
ole
in
a
uthentica
ti
on
a
nd
identi
f
ica
ti
on
in
tw
o
wa
y
s
,
whe
r
e
ve
r
the
e
nc
oding
s
uppor
t
g
r
e
a
t
r
ole
of
the
a
uthentica
ti
on.
T
he
e
nc
r
ypti
on
c
a
n
give
s
e
c
ur
it
y
f
o
r
da
ta
t
r
a
ns
f
or
mation
a
nd
s
tor
ing
a
uthentica
ti
on
da
ta.
F
ur
ther
mor
e
,
the
e
nc
r
ypti
on
c
ould
us
e
it
a
s
a
n
a
uthentica
ti
on
method
[
3
,
4
]
.
T
he
e
nc
r
ypti
on
s
uppor
ts
a
uthentica
ti
on
by
us
ing
it
in
the
a
uthentica
ti
on
s
y
s
tems
,
e
x.
s
ys
tems
of
the
pa
s
s
wor
d
e
nc
r
ypti
on
a
r
e
us
ua
ll
y
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
S
N
:
1693
-
6930
T
E
L
KO
M
NI
KA
T
e
lec
omm
un
C
omput
E
l
C
ontr
o
l
,
Vol.
1
8
,
No
.
5
,
Oc
tober
2020:
2543
-
2548
2544
us
e
d
e
nc
r
ypted
pa
s
s
wor
d
a
nd
us
e
c
ode
e
nc
r
ypti
on
a
nd
c
a
r
d
s
ys
tem
to
pr
otec
t
im
por
tant
inf
o
r
mation,
a
ls
o
us
e
pa
s
s
wor
d
c
r
e
a
tor
f
or
r
a
ndom
e
nc
r
ypti
o
n
pa
s
s
wor
ds
.
T
he
e
nc
r
ypti
on
is
us
ua
ll
y
us
e
d
in
pa
r
ti
c
ular
a
pp
li
c
a
ti
ons
to
tr
a
ns
f
e
r
a
uthentica
ti
on
inf
o
r
mation
a
nd
da
ta
f
r
om
one
to
a
nother
s
ys
tem
by
a
ne
twor
k
a
s
we
ll
a
s
a
uthentica
ti
on
s
ys
tems
by
e
nc
r
ypti
on
de
pe
nd
on
pr
ivate
c
r
yp
tos
ys
tems
or
publi
c
ke
y
c
r
y
pt
os
ys
tems
.
T
he
main
c
r
yptog
r
a
phic
s
ys
tems
us
e
one
ke
y
f
or
de
c
r
ypti
on
a
nd
e
nc
r
ypti
on
f
unc
ti
ons
.
Authe
nti
c
a
ti
on
s
ys
tems
ba
s
e
d
on
pr
ivate
c
r
yptogr
a
phic
s
ys
tems
r
e
ly
on
a
c
omm
on
ke
y
be
twe
e
n
the
us
e
r
who
log
s
in
a
nd
the
a
uthentica
ti
on
s
ys
tem.
C
omm
on
c
r
yptogr
a
phi
c
s
ys
tems
de
c
ode
e
nc
r
ypt
ing
a
nd
de
c
r
ypti
ng
f
unc
ti
ons
by
s
e
pa
r
a
te
a
mong
the
ke
ys
.
E
nc
r
ypted
a
uthentica
ti
o
ns
s
ys
tems
de
pe
nd
on
the
publi
c
ke
y
of
the
c
r
ypt
ogr
a
phic
s
ys
tems
r
e
ly
[
5
-
7
].
F
igur
e
1.
I
nteg
r
it
y
o
f
mes
s
a
ge
[
2
]
3.
HAS
H
F
UN
CT
I
ON
T
he
Ha
s
h
a
lgor
it
hm
tr
a
c
ks
binar
y
da
ta
,
a
nd
pr
oduc
e
s
a
n
int
e
ns
ive
r
e
pr
e
s
e
ntation,
c
a
ll
e
d
the
"
M
e
s
s
a
g
e
S
umm
a
r
y"
.
T
he
e
nc
r
ypti
on
a
lgo
r
it
hm
is
a
Ha
s
h
a
lgor
it
hm
made
f
or
s
e
c
ur
it
y
f
e
a
tur
e
s
.
T
he
S
tanda
r
d
HA
S
H
-
180
including
(
S
HA
-
256,
S
HA
-
1,
S
HA
-
224,
S
HA
-
384,
a
nd
S
HA
-
512,
f
or
mor
e
inf
or
mation
the
s
tanda
r
d
ha
s
h
is
c
omm
on
us
e
d
b
y
moder
n
inf
or
mation
tec
hnology.
I
n
las
t
ye
a
r
s
,
t
he
r
e
a
r
e
s
e
ve
r
a
l
a
tt
a
c
ks
a
ga
in
s
t
NI
S
T
a
lgor
it
hms
,
but
it
f
a
il
e
d,
e
s
pe
c
ially
a
ga
ins
t
S
HA
-
1.
NI
S
T
he
ld
man
y
publi
c
wor
ks
hops
f
or
e
s
ti
mation
the
s
tatus
of
a
lgo
r
it
hms
.
De
pe
nd
on
the
wor
ks
hops
;
NI
S
T
s
ugge
s
ted
mor
e
t
ha
n
one
a
ddit
ional
a
lgor
i
thm
by
ge
ne
r
ic
c
ompetit
ion.
And
NI
S
T
s
ugge
s
ted
a
ti
meta
ble
f
or
tes
ti
ng
a
nd
publi
s
he
d
ne
w
us
ing
poli
c
y
of
the
Ha
s
h
f
unc
ti
ons
[
8,
9
].
4.
CR
YP
T
OG
RA
P
HI
C
HAS
H
F
UN
CT
I
ON
T
h
e
f
u
nc
ti
on
o
f
ha
s
hi
ng
f
r
a
g
me
nta
t
io
n
is
a
ne
c
e
s
s
a
r
y
p
r
oc
e
du
r
e
t
a
ke
s
a
n
b
lo
c
k
in
g
of
t
he
a
r
b
it
r
a
r
y
da
ta
a
nd
r
e
-
ba
c
ks
a
f
ix
e
d
s
ize
b
it
s
t
r
i
ng
,
a
n
d
c
o
d
in
g
va
lue
o
f
t
he
ha
s
h
,
l
ik
e
c
h
a
n
ge
s
of
ha
s
h
v
a
l
ue
s
.
T
he
e
nc
od
e
d
da
ta
a
r
e
us
ua
ll
y
be
i
ng
t
he
mes
s
a
ge
,
o
f
ten
n
a
me
d
th
e
mes
s
a
ge
s
e
g
me
nt
a
t
io
n
va
l
ue
o
r
s
um
ma
r
ize
d
m
e
r
e
ly
.
T
he
c
r
yptogr
a
phic
f
unc
ti
on
ha
s
s
e
ve
r
a
l
c
ha
r
a
c
ter
is
t
ics
:
−
E
a
s
y
to
c
a
lcula
te
the
r
e
tail
va
lue
o
f
a
pa
r
ti
c
ular
me
s
s
a
ge
−
Not
f
e
a
s
ibl
e
f
or
looki
ng
f
or
a
mes
s
a
ge
c
ontaining
a
s
pe
c
if
ic
s
e
gmenta
ti
on
−
Us
e
les
s
to
c
ha
nging
mes
s
a
ge
without
a
ny
modi
f
ie
d
the
ti
c
k
−
Not
f
e
a
s
ibl
e
to
look
f
or
two
mes
s
a
ge
s
in
the
s
a
me
ti
c
ke
r
E
nc
r
ypti
on
f
unc
ti
ons
c
ontain
s
e
ve
r
a
l
da
ta
s
e
c
ur
it
y
s
of
twa
r
e
,
pa
r
ti
c
ular
ly
in
mes
s
a
ge
a
uthentica
ti
on
a
nd
digi
tal
s
ignatur
e
s
.
I
t
c
a
n
a
ls
o
us
e
nor
mal
r
e
tail
f
unc
ti
ons
,
f
or
index
da
ta
in
the
r
e
tail
table
s
,
to
take
f
inger
pr
int
s
,
to
de
ter
mi
ne
r
e
pe
a
ted
s
a
me
da
ta
o
r
u
nique
da
ta,
a
nd
a
s
a
c
he
c
ks
um
to
de
te
r
mi
ne
a
ny
c
or
r
upti
on
in
the
da
ta
[
10
,
11
].
T
he
f
unc
ti
on
of
the
HA
S
H
e
nc
r
ypti
on
s
hould
be
including
a
ll
kinds
of
c
r
ypt
a
na
lyt
ic
a
tt
a
c
k.
T
ha
t
s
hould
ha
ve
the
f
oll
owing
c
ha
r
a
c
ter
s
:
−
P
r
e
im
a
ge
r
e
s
is
tanc
e
:
B
e
c
a
us
e
of
f
r
a
gmenta
ti
on
,
it
’
s
ve
r
y
ha
r
d
to
f
ound
a
mes
s
a
g
e
.
T
ha
t
li
nk
e
d
to
the
c
onc
e
pt
of
the
one
-
wa
y
f
unc
ti
on.
W
it
hou
t
that
a
r
e
vulner
a
ble.
−
S
e
c
ond
pr
e
im
a
ge
r
e
s
is
tanc
e
:
I
t’
s
include
d
the
i
nputs
whe
r
e
ve
r
f
indi
ng
other
inpu
ts
.
S
ometim
e
s
that
indi
c
a
tes
f
or
low
im
pa
c
t
r
e
s
is
tanc
e
,
without
thes
e
f
unc
ti
ons
a
r
e
mea
n
pr
e
vious
pr
e
-
a
tt
a
c
k
a
tt
a
c
ks
[
12]
.
4.
1.
Cr
yp
t
ogr
ap
h
ic
h
as
h
f
u
n
c
t
ion
s
s
e
c
u
r
it
y
4
.1
.
1.
Ve
r
if
yin
g
m
e
s
s
age
s
in
t
e
gr
it
y
M
e
s
s
a
ge
int
e
gr
it
y
is
one
of
the
a
ppli
c
a
ti
ons
f
or
s
e
c
ur
e
f
r
a
gmenta
ti
on.
B
y
that
c
ould
de
ter
mi
ne
the
c
ha
nge
s
to
a
mes
s
a
ge
,
a
r
e
it
ha
s
be
e
n
made
,
e
s
pe
c
ially
in
the
c
ompar
ing
be
twe
e
n
be
f
or
e
a
nd
a
f
ter
s
e
nding
the
mes
s
a
ge
.
M
o
s
t
digi
tal
s
ignatur
e
a
lgor
it
hms
a
r
e
us
e
d
to
c
onf
ir
mi
ng
the
va
li
dit
y
of
the
s
igne
d
mes
s
a
ge
,
Evaluation Warning : The document was created with Spire.PDF for Python.
T
E
L
KO
M
NI
KA
T
e
lec
omm
un
C
omput
E
l
C
ontr
o
l
A
ne
w
algor
it
hm
for
implem
e
nti
ng
me
s
s
age
authentication
and
int
e
gr
it
y
in
… (
A
laa
W
agih
A
bdul
Qad
e
r
)
2545
whe
r
e
ve
r
the
s
ignatur
e
is
pr
oo
f
of
mes
s
a
ge
a
uthe
nti
c
it
y.
T
he
pa
r
ti
c
ular
a
nd
s
pe
c
if
ic
a
ppli
c
a
ti
on
is
doing
by
pa
s
s
wor
d
c
onf
ir
mation.
W
he
r
e
ve
r
the
pa
s
s
wor
ds
a
r
e
s
tor
e
s
a
s
s
umm
a
r
y
text.
F
o
r
a
uthentica
te
of
t
he
us
e
r
,
the
pa
s
s
wor
d
is
divi
de
d
a
nd
c
om
pa
r
e
d
to
the
s
tor
e
d
tes
t.
4.
1.
2.
F
il
e
or
d
a
t
a
i
d
e
n
t
if
ier
Of
ten
c
od
ing
mana
ge
ment
s
ys
tems
,
e
xa
mpl
e
M
e
r
c
ur
ial,
Git,
M
onotone
a
nd
s
ha
1s
um
us
e
many
kinds
of
c
ontent
(
pe
dig
r
e
e
inf
or
mation,
d
ir
e
c
tor
y
t
r
e
e
s
a
nd
f
il
e
c
ontent,
e
tc.
)
to
make
it
unique.
T
he
f
unc
ti
on
of
the
e
nc
oding
is
de
ter
mi
ning
f
il
e
-
s
ha
r
ing
ne
twor
ks
(
pe
e
r
-
to
-
pe
e
r
)
,
e
x.
in
a
n
(
e
d2k)
li
nk,
a
n
(
M
D4)
va
r
iable
is
mer
ge
d
with
t
he
f
il
e
s
ize
,
whe
r
e
ve
r
,
givi
ng
s
uf
f
icie
nt
da
ta
to
identif
ica
ti
on
f
il
e
s
s
our
c
e
s
a
nd
downloa
d
the
f
il
e
.
M
a
gne
t
bonds
a
r
e
a
nothe
r
e
xa
mpl
e
.
T
his
f
r
a
gmenta
ti
on
is
o
f
ten
the
highes
t
s
e
gmenta
ti
on
in
t
he
r
e
tail
li
s
t
or
the
r
e
tail
t
r
e
e
that
a
ll
ows
other
be
ne
f
it
s
.
T
he
f
unc
ti
on
of
the
ha
s
h
a
ppli
c
a
ti
ons
a
ll
ows
a
quick
s
e
a
r
c
h
of
da
ta
in
a
ha
s
h
table
.
A
s
pe
c
if
ic
type
of
Ha
s
h
f
unc
ti
ons
,
the
e
nc
r
ypti
on
f
r
a
gmenta
ti
on
f
unc
ti
ona
li
ty
of
f
e
r
s
it
s
e
lf
we
ll
f
or
thi
s
a
ppli
c
a
ti
on
a
s
we
ll
.
How
e
ve
r
,
c
ompa
r
e
d
to
s
tanda
r
d
r
e
tail
f
unc
ti
o
ns
,
f
unc
ti
ons
o
f
the
e
n
c
r
ypti
on
de
f
r
a
gmenta
ti
on
a
r
e
mo
r
e
e
xpe
ns
ive
than
the
c
a
lcula
ti
on
whe
r
e
ve
r
it
is
ne
c
e
s
s
a
r
y
to
pr
o
tec
t
a
ga
ins
t
the
f
r
a
ud
c
r
e
a
ti
ng
inf
or
mation
a
bs
tr
a
c
ted
f
r
o
m
e
xpe
c
ted
da
ta
[
13
-
1
5
].
4.
2.
Has
h
f
u
n
c
t
ion
s
d
e
p
e
n
d
on
b
lock
c
i
p
h
e
r
s
M
a
ny
methods
a
r
e
us
e
d
f
or
block
c
iphe
r
f
or
buil
d
f
unc
ti
on
of
the
c
r
yptogr
a
phic
ha
s
h,
pa
r
ti
c
ular
ly
f
unc
ti
on
of
the
one
-
wa
y
c
o
mpr
e
s
s
ion
.
T
he
meth
ods
s
a
me
block
c
ipher
methods
,
whe
r
e
ve
r
both
us
e
d
f
or
e
nc
r
ypti
on.
T
he
ha
s
h
f
unc
ti
ons
a
r
e
e
xa
mpl
e
M
D5
,
M
D4,
S
HA
-
2
a
nd
S
HA
-
1
a
nd
a
r
e
de
s
igned
f
o
r
t
he
s
a
me
pur
pos
e
,
S
HA
-
3
f
inalis
ts
ha
ve
f
unc
ti
ons
with
bloc
k
-
c
ipher
s
uc
h
a
s
(
e
.
g.
B
L
AK
E
,
S
ke
in
,
)
a
nd
(
e
.
g.
,
Ke
c
c
a
k,
JH
)
[
16
-
18
]
.
A
s
tanda
r
d
block
c
ipher
li
ke
(
A
E
S
)
us
e
d
ins
tea
d
of
block
c
ipher
s
.
T
he
y
us
e
blocks
a
nd
lar
ge
ke
ys
,
c
ould
c
ha
nging
a
ll
ke
ys
of
a
ll
block,
a
nd
make
to
r
e
s
is
tanc
e
ke
y
a
tt
a
c
ks
.
T
he
r
e
a
r
e
s
e
ve
r
a
l
goa
ls
of
t
he
ge
ne
r
a
l
c
ipher
s
.
AE
S
ha
s
ke
y
s
ize
s
whic
h
make
it
nontr
ivi
a
l
to
us
ing
to
c
r
e
a
te
long
ha
s
h
va
lues
;
whe
n
ke
y
c
ha
nge
s
e
a
c
h
block,
the
AE
S
e
nc
r
ypti
on
be
c
omes
without
or
les
s
e
f
f
icie
nt;
a
nd
ke
y
a
tt
a
c
ks
make
it
without
s
e
c
ur
it
y
[
19]
.
F
igu
r
e
2
s
hows
the
M
e
r
kle
–
Da
mgår
d
c
ons
tr
uc
ti
on
.
F
igur
e
2.
M
e
r
kle
–
Da
mgår
d
c
ons
tr
uc
ti
on
[
19]
4.
3.
Cr
yp
t
ogr
ap
h
ic
e
n
c
r
yp
t
ion
algori
t
h
m
s
T
he
ha
s
h
f
unc
ti
on
us
ed
in
c
omput
e
r
s
c
ienc
e
s
,
a
nd
it
mea
ns
s
tr
ing
c
ompr
e
s
s
ion
f
unc
ti
on
of
a
r
bit
r
a
r
y
input
to
a
s
e
r
ies
of
f
ixed
length.
B
ut,
i
f
it
ha
s
s
ome
of
the
a
ddit
ional
r
e
quir
e
ments
,
it
c
ould
us
e
it
in
the
e
nc
r
ypti
on
a
ppli
c
a
ti
ons
.
T
he
r
e
a
r
e
many
e
nc
ode
d
f
unc
ti
ons
,
but
many
of
it
is
we
a
k.
I
f
the
j
a
mm
ing
f
unc
t
ion
is
not
a
s
uc
c
e
s
s
,
a
s
uc
c
e
s
s
f
ul
a
tt
a
c
k
a
ga
ins
t
it
de
c
r
e
a
s
e
s
e
xpe
r
t
c
onf
idenc
e
.
E
x.
i
n
2004,
vulner
a
bil
it
ies
we
r
e
oc
c
ur
r
ing
in
a
ha
s
h
f
unc
ti
on
s
uc
h
a
s
R
I
P
E
M
D,
M
D5
a
nd
S
HA
-
0.
T
ha
t
will
be
pr
ovide
long
-
ter
m
s
e
c
ur
it
y
of
the
s
ubs
e
que
nt
f
unc
ti
on
de
r
ived
f
r
om
thes
e
HA
ASH
e
xa
mpl
e
,
S
HA
-
1,
R
I
P
E
M
D
-
12
8
a
nd
R
I
P
E
M
D
-
160.
R
I
P
E
M
D
a
nd
S
HA
-
0
a
r
e
not
c
omm
only
us
ing
a
nd
it
r
e
plac
e
d
by
a
ne
w
im
pr
ove
d
ve
r
s
ion.
M
D5
a
nd
S
HA
-
1
da
lt
ons
be
c
ome
c
omm
only
us
e
d
a
t
2009,
a
lt
hough
a
ll
that
M
D5
wa
s
br
oke
n
whe
r
e
ve
r
the
a
tt
a
c
k
wa
s
done
a
ga
ins
t
it
in
2008.
T
he
y
a
r
e
de
ve
lopi
ng
S
HA
-
0
a
nd
S
HA
-
1
f
unc
ti
on
by
NS
A.
Als
o,
a
s
tr
ong
a
tt
a
c
k
wa
s
done
on
S
HA
-
1
in
2005.
F
u
r
ther
mor
e
,
s
uc
c
e
s
s
f
ul,
s
tr
ong
a
tt
a
c
k
oc
c
ur
r
e
d
in
2005
on
S
HA
-
1
a
nd
f
ound
c
oll
is
ions
in
(
263)
ope
r
a
ti
ons
.
A
ls
o,
ther
e
a
r
e
we
a
kne
s
s
e
s
point
s
of
S
HA
-
1,
s
ugge
s
ti
ng
that
it
ne
e
d
s
e
ve
r
a
l
ye
a
r
s
to
b
r
e
a
k
i
t.
T
he
r
e
a
r
e
othe
r
ne
w
a
ppli
c
a
ti
ons
pr
o
tec
t
a
ga
ins
t
the
matter
s
by
us
ing
a
nother
S
HA
,
li
ke
S
HA
-
2,
o
r
ne
w
tec
hniques
li
ke
r
a
ndom
de
f
r
a
gmenta
ti
on
[
20
-
23]
.
To
p
r
oduc
e
ne
w
a
p
pli
c
a
ti
ons
,
us
e
Ha
s
h
f
unc
ti
ons
,
ther
e
is
s
tr
ong
c
ompetit
ion
f
or
de
ve
lopi
ng
S
HA
-
2
to
pr
oduc
e
S
HA
-
3
in
2012
[
24,
25]
.
T
he
f
oll
owing
a
lgor
it
hms
a
r
e
us
ua
ll
y
us
e
d
in
c
r
ypt
ogr
a
phy
a
s
F
igur
e
3
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
S
N
:
1693
-
6930
T
E
L
KO
M
NI
KA
T
e
lec
omm
un
C
omput
E
l
C
ontr
o
l
,
Vol.
1
8
,
No
.
5
,
Oc
tober
2020:
2543
-
2548
2546
F
igur
e
3.
F
a
mi
ly
of
ha
s
h
f
unc
ti
ons
[
17
]
4.
4.
A
p
r
op
os
e
d
h
as
h
algorit
h
m
A
h
a
s
h
f
u
nc
ti
on
s
h
ou
ld
ha
v
e
th
e
a
b
il
it
y
t
o
p
r
oc
e
s
s
i
ng
r
a
nd
om
len
gt
h
mes
s
a
g
e
in
to
a
n
ou
tp
u
t
ha
v
e
f
ix
e
d
l
e
n
g
th
.
A
ls
o
,
p
os
s
i
bl
e
br
e
a
ki
ng
f
i
xe
d
l
e
n
gt
h
i
np
ut
i
n
to
a
s
e
r
i
e
s
of
b
l
oc
ks
h
a
s
e
q
ua
l
s
ize
a
nd
us
in
g
a
o
ne
-
wa
y
c
om
p
r
e
s
s
io
n
f
un
c
t
io
n
.
I
n
th
is
a
lg
o
r
i
th
m
,
we
a
s
s
u
me
d
t
h
r
e
e
r
o
un
ds
,
in
e
a
c
h
r
o
un
d
t
he
r
e
is
32
-
it
e
r
a
ti
on
.
T
h
e
o
ut
pu
t
o
f
a
n
y
l
e
n
gt
h
o
f
the
i
np
ut
is
9
6
-
b
it
.
W
e
us
e
d
l
og
ic
a
l
op
e
r
a
t
o
r
s
(
a
n
d
,
o
r
,
xo
r
,
s
hl
,
s
hl
r
,
s
h
r
r
).
4.
4.
1.
Ou
t
li
n
e
o
f
a
p
r
op
os
e
d
h
as
h
algori
t
h
m
T
he
f
ir
s
t
s
tep
is
ge
ne
r
a
ted
o
f
64
ke
y
[
311.
.
.
2
]
plus
32
-
bit
pr
opos
e
d
ke
y
)
.
S
e
c
ondly
,
it
take
s
a
n
input
mes
s
a
ge
a
nd
br
e
a
k
s
int
o
n
-
512
-
bit
block
s
then
e
a
c
h
block
br
e
a
k
int
o
of
64
wor
d
(
32
-
bit
)
modi
f
i
e
d
us
ing
(
s
pe
c
ial
e
qua
ti
ons
to
r
e
-
c
ha
nge
or
igi
na
l
wor
d)
,
s
e
e
F
igur
e
4.
T
he
n
take
e
a
c
h
block
a
nd
do
two
s
pe
c
ial
r
ounds
on
it
;
f
inally
do
s
pe
c
ial
e
qua
ti
ons
on
A,
B
,
C
,
D
(
32
-
bit
va
r
iable
s
)
,
s
e
e
f
igu
r
e
a
nd
then
c
ontr
a
c
ti
on
of
them
,
s
e
e
F
igur
e
5.
F
igur
e
4
.
Outli
ne
o
f
ne
w
one
-
wa
y
ha
s
h
f
unc
ti
on
f
l
owc
ha
r
t
F
igur
e
5
.
Outli
ne
the
f
lowc
ha
r
t
to
re
-
c
ha
nge
the
or
igi
na
l
wo
r
d
Evaluation Warning : The document was created with Spire.PDF for Python.
T
E
L
KO
M
NI
KA
T
e
lec
omm
un
C
omput
E
l
C
ontr
o
l
A
ne
w
algor
it
hm
for
implem
e
nti
ng
me
s
s
age
authentication
and
int
e
gr
it
y
in
… (
A
laa
W
agih
A
bdul
Qad
e
r
)
2547
4.
4.
2.
T
h
e
f
irs
t
p
r
op
os
e
d
f
u
n
c
t
ion
:
I
n
thi
s
f
unc
ti
on
,
we
s
hif
t
le
f
t
the
f
i
r
s
t
va
r
iable
A
f
ir
s
t
by
9
a
nd
s
e
c
ondly
s
hif
t
r
ight
by
7
the
e
xc
lus
ive
or
of
them
;als
o
s
hif
ti
ng
the
va
r
iable
s
(
B
by
lef
t
3,
C
by
r
igh
t
4
a
nd
D
by
le
f
t
5
)
then
e
xc
lus
ive
or
of
them
;bec
a
us
e
the
be
s
t
s
hif
ti
ng
number
that
it
s
obtaine
d
e
xa
c
tl
y
dif
f
e
r
e
nt
r
e
s
ult
s
a
ls
o
not
us
e
d
in
a
not
he
r
ha
s
h
f
unc
ti
ons
a
f
ter
e
xa
mi
ne
d
d
if
f
e
r
e
nt
number
s
o
f
s
hif
t
a
nd
dif
f
e
r
e
nt
a
nother
logi
c
a
l
ope
r
a
to
r
s
,
s
e
e
F
igur
e
6.
4.
4.
3.
T
h
e
s
e
c
on
d
f
u
n
c
t
ion
I
n
thi
s
f
unc
ti
on,
we
s
hif
t
lef
t
r
otate
the
f
ir
s
t
va
r
i
a
ble
A
f
i
r
s
t
by
12
a
nd
s
e
c
ondly
s
hif
t
r
ight
r
otate
by
15
the
e
xc
lus
ive
or
of
them.
A
ls
o,
e
xc
lus
ive
or
of
not
va
r
iable
C
a
nd
va
r
iable
D
,
b
e
c
a
us
e
the
be
s
t
s
hif
ti
ng
number
that
it
s
obtaine
d
e
xa
c
tl
y
dif
f
e
r
e
nt
r
e
s
ult
s
a
ls
o
no
t
us
e
d
in
a
nother
ha
s
h
f
unc
ti
ons
a
f
ter
e
xa
mi
ne
d
dif
f
e
r
e
nt
numbe
r
s
of
s
hif
t
a
nd
d
if
f
e
r
e
nt
a
nother
log
ica
l
ope
r
a
tor
s
,
s
e
e
F
igu
r
e
7.
F
igur
e
6.
S
pe
c
if
ic
e
qua
ti
on
f
o
r
the
f
ir
s
t
r
ound
F
igur
e
7.
S
pe
c
if
ic
e
qua
ti
on
f
o
r
the
s
e
c
ond
r
ound
4.
4.
4.
Var
iab
les
m
od
if
icat
io
n
T
o
make
a
pe
r
f
e
c
t
modi
f
ica
ti
on
a
f
te
r
T
W
O
r
oun
ds
va
r
iable
s
will
be
modi
f
ied
by
s
pe
c
ial
f
or
mal
to
e
nha
nc
e
the
r
e
s
ult
s
with
e
xa
c
tl
y
dif
f
e
r
e
nt
other
s
,
it
make
us
e
of
Xor
,
s
hl
,
s
hr
r
,
s
e
e
F
igur
e
8.
F
or
the
C
ompl
e
xit
y
mea
s
ur
e
ments
.
T
he
ha
s
h
f
unc
ti
o
n
is
looki
ng
f
or
mes
s
a
ge
a
gr
e
e
d
with
a
given
me
s
s
a
ge
by
us
ing
a
b
r
ute
f
or
c
e
s
e
a
r
c
h
2
L
e
va
luations
,
whe
r
e
L
r
e
pr
e
s
e
nts
bit
s
number
of
the
ke
y
wi
th
p
r
opos
e
d
va
r
iable
s
length.
T
ha
t
na
med
p
r
e
-
im
a
ge
is
a
tt
a
c
king.
And
the
s
e
c
ond
f
a
c
tor
is
looki
ng
f
o
r
two
mes
s
a
ge
s
(
d
if
f
e
r
e
nt)
whic
h
pr
oduc
e
the
s
a
me
mes
s
a
ge
diges
t,
that
na
m
e
d
c
oll
is
ion,
a
nd
that
ne
e
d
to
a
ve
r
a
ge
only
2
L
/
2
e
v
a
luations
us
ing
a
bir
thday
a
tt
a
c
k.
I
n
the
p
r
opos
e
d
ha
s
h
a
lgor
it
hm,
we
us
e
d
32
-
bit
ke
y
length
in
a
ddit
ion
to
the
pr
opos
e
d
thr
e
e
va
r
iable
s
e
a
c
h
of
32
-
bit
length;
s
o,
the
br
ute
f
or
c
e
will
make
a
n
e
xha
us
ti
ve
s
e
a
r
c
h
of
de
gr
e
e
2
128
.
(
a
)
(
b)
(
c
)
(
d)
F
igur
e
8.
U
pda
te
of
va
r
iable
s
;
(
a
)
v
a
r
iable
A
,
(
b
)
v
a
r
iable
B
, (
c
)
v
a
r
iable
C
,
(
d)
v
a
r
iable
D
5.
CONC
L
USI
ONS
W
e
ha
ve
s
hown
in
thi
s
pa
p
e
r
how
c
r
yptogr
a
phic
ha
s
h
f
unc
ti
ons
c
a
nnot
f
ind
two
dif
f
e
r
e
nt
mes
s
a
ge
s
ha
ve
r
e
s
e
mbl
e
d
ha
s
h
va
lue.
I
t
is
not
br
oke
n
be
c
a
us
e
of
the
de
gr
e
e
of
c
onf
us
ion
a
nd
c
ompl
e
xit
y
is
v
e
r
y
high,
a
nd
a
n
a
tt
a
c
ke
r
c
a
nnot
f
a
ke
a
s
ignatur
e
in
a
pa
r
ti
c
ular
c
omput
ing
e
nvir
onment
.
a
ny
mes
s
a
ge
will
be
s
a
ve
d
a
nd
will
ge
t
s
ign
,
i
f
the
mes
s
e
ge
is
c
ha
nge
d
will
ge
t
ne
w
s
ignatur
e
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
S
N
:
1693
-
6930
T
E
L
KO
M
NI
KA
T
e
lec
omm
un
C
omput
E
l
C
ontr
o
l
,
Vol.
1
8
,
No
.
5
,
Oc
tober
2020:
2543
-
2548
2548
RE
F
E
RE
NC
E
[1
]
S.
B.
T
h
i
g
a
l
e,
R.
K
.
Pan
d
e
y
,
P.
R.
G
ad
ek
ar,
an
d
V
.
A
.
D
h
o
t
re,
“L
i
g
h
t
w
ei
g
h
t
n
o
v
e
l
t
r
u
s
t
-
b
a
s
ed
frame
w
o
r
k
fo
r
I
o
T
en
ab
l
ed
w
i
re
l
es
s
n
et
w
o
r
k
co
mm
u
n
i
cat
i
o
n
s
,
”
P
er
i
o
d
i
c
a
l
s
of
E
n
g
i
n
eer
i
n
g
a
n
d
N
a
t
u
r
a
l
S
c
i
e
n
ce
,
v
o
l
.
7
,
n
o
.
3
,
p
p
.
1
1
2
6
–
1
1
3
7
,
2
0
1
9
.
[2
]
M.
Z
i
a
an
d
R.
A
l
i
,
"
Cry
p
t
an
al
y
s
i
s
an
d
i
m
p
ro
v
eme
n
t
o
f
an
el
l
i
p
t
i
c
cu
r
v
e
b
as
e
d
s
i
g
n
cr
y
p
t
i
o
n
s
c
h
eme
fo
r
fi
rew
a
l
l
s
,
"
P
l
o
S
O
n
e
,
v
o
l
.
1
3
,
n
o
.
1
2,
p
p
.
e
0
2
0
8
8
5
7
-
e0
2
0
8
8
5
7
,
2
0
1
8
.
[3
]
S.
D
ey
,
S.
Samp
a
l
l
i
an
d
Q
.
Y
e,
"
MD
A
:
mes
s
ag
e
d
i
g
e
s
t
-
b
as
e
d
au
t
h
e
n
t
i
cat
i
o
n
fo
r
mo
b
i
l
e
cl
o
u
d
co
m
p
u
t
i
n
g
,
"
Jo
u
r
n
a
l
o
f
Cl
o
u
d
Co
m
p
u
t
i
n
g
,
v
o
l
.
5
,
n
o
.
1,
p
p
.
1
-
1
3
,
2
0
1
6
.
[4
]
M.
H
arran
,
W
.
Farrel
l
y
a
n
d
K
.
Cu
rran
,
"
A
me
t
h
o
d
f
o
r
v
eri
f
y
i
n
g
i
n
t
eg
r
i
t
y
&
au
t
h
e
n
t
i
cat
i
n
g
d
i
g
i
t
a
l
med
i
a,
"
A
p
p
l
i
e
d
Co
m
p
u
t
i
n
g
a
n
d
In
f
o
r
m
a
t
i
cs
,
v
o
l
.
1
4
,
n
o
.
2,
p
p
.
1
4
5
-
1
5
8
,
2
0
1
8
.
[5
]
L
.
Ferr
et
t
i
et
al
.
,
"
A
s
y
mmet
ri
c
cry
p
t
o
g
ra
p
h
i
c
s
ch
eme
fo
r
d
at
a
i
n
t
e
g
ri
t
y
v
er
i
fi
ca
t
i
o
n
i
n
c
l
o
u
d
d
at
a
b
as
e
s
,
"
In
f
o
r
m
a
t
i
o
n
S
ci
en
ce
s
,
v
o
l
.
4
2
2
,
p
p
.
4
9
7
-
5
1
5
,
2
0
1
8
.
[6
]
M.
A
.
A
l
azzaw
i
et
al
.
,
"
E
ffi
ci
e
n
t
Co
n
d
i
t
i
o
n
al
A
n
o
n
y
m
i
t
y
w
i
t
h
Mes
s
a
g
e
In
t
e
g
ri
t
y
an
d
A
u
t
h
e
n
t
i
cat
i
o
n
i
n
a
V
e
h
i
c
u
l
a
r
Ad
-
H
o
c
N
e
t
w
o
rk
,
"
IE
E
E
A
cce
s
s
,
v
o
l
.
7
,
p
p
.
7
1
4
2
4
-
7
1
4
3
5
,
2
0
1
9
.
[7
]
K
.
D
i
n
g
,
S.
Ch
en
a
n
d
F.
Men
g
,
"
A
N
o
v
e
l
Percep
t
u
al
H
as
h
A
l
g
o
r
i
t
h
m
fo
r
M
u
l
t
i
s
p
ec
t
ral
Im
ag
e
A
u
t
h
e
n
t
i
cat
i
o
n
,
"
A
l
g
o
r
i
t
h
m
s
,
v
o
l
.
1
1
,
n
o
.
1
-
14
,
p
p
.
6
,
2
0
1
8
.
[8
]
B.
A
l
o
ma
i
r,
"
A
u
t
h
en
t
i
ca
t
ed
e
n
cry
p
t
i
o
n
:
h
o
w
reo
rd
er
i
n
g
can
i
m
p
act
p
erfo
rma
n
ce,
"
S
ecu
r
i
t
y
a
n
d
Co
m
m
u
n
i
ca
t
i
o
n
Net
wo
r
ks
,
v
o
l
.
9
,
n
o
.
1
8
,
p
p
.
6
1
7
3
-
6
1
8
8
,
2
0
1
6
.
[9
]
P.
V
i
j
ay
a
k
u
mar
et
al
.
,
"
Co
mp
u
t
at
i
o
n
al
l
y
effi
ci
e
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1
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,
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[2
2
]
C.
Bi
s
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[2
3
]
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.
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s
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.
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.
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,
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Sc
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.
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.
[2
4
]
A
.
J
.
Men
ezes
,
P.
C.
v
an
O
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t
,
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A
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.
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.
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[2
5
]
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.
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.
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