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m
o
d
el
p
r
o
v
id
ed
ac
co
r
d
in
g
to
a
g
i
v
e
n
d
escr
ip
tio
n
l
an
g
u
a
g
e.
T
h
e
m
ai
n
ch
alle
n
g
e
p
r
o
v
id
er
s
o
f
N
FV
s
o
f
t
w
ar
e
h
a
v
e
to
f
ac
e
i
n
o
r
d
er
to
en
ab
le
f
o
r
m
a
l
v
er
if
ica
tio
n
o
f
v
ir
t
u
alize
d
n
et
w
o
r
k
s
is
t
h
e
m
o
d
el
co
n
s
tr
u
ctio
n
:
t
h
er
e
is
a
lar
g
e
s
e
m
a
n
ti
c
g
ap
b
et
w
ee
n
t
h
e
ar
ti
f
ac
ts
p
r
o
d
u
ce
d
b
y
s
o
f
t
w
ar
e
d
ev
elo
p
er
s
an
d
th
o
s
e
ac
ce
p
ted
b
y
cu
r
r
en
t
v
er
i
f
icatio
n
to
o
ls
.
Fo
r
ex
a
m
p
le,
p
o
w
er
f
u
l
ap
p
r
o
ac
h
es
s
u
c
h
a
s
[
2
]
an
d
[
5
]
h
a
v
e
alr
ea
d
y
e
v
o
l
v
ed
f
r
o
m
r
esear
ch
a
n
d
ar
e
n
o
w
b
ei
n
g
r
o
lled
in
to
p
r
o
d
u
ctio
n
,
b
u
t
th
is
g
ap
m
i
g
h
t
b
e
a
s
ig
n
i
f
ica
n
t
h
u
r
d
le
f
o
r
th
eir
w
i
d
e
ad
o
p
tio
n
in
r
ea
l
n
et
w
o
r
k
e
n
v
ir
o
n
m
en
ts
.
I
n
ess
e
n
ce
,
th
e
s
e
to
o
ls
ar
e
b
ased
o
n
a
co
m
p
le
x
m
o
d
elin
g
tec
h
n
iq
u
e,
ten
d
to
lo
ck
th
e
u
s
er
in
to
a
s
in
g
le
k
i
n
d
o
f
c
h
ec
k
i
n
g
tech
n
o
lo
g
y
,
r
eq
u
ir
e
to
ac
cu
r
atel
y
m
o
d
el
n
et
w
o
r
k
f
u
n
ctio
n
alit
y
,
w
h
ic
h
r
elies
o
n
ex
p
er
t
in
p
u
t,
an
d
u
s
u
all
y
o
b
lig
e
d
ev
elo
p
er
s
to
lear
n
a
w
h
o
le
n
e
w
la
n
g
u
a
g
e
(
e.
g
.
,
SE
FL
i
n
[
5
]
)
.
T
h
is
m
o
ti
v
ate
s
t
h
e
w
o
r
k
p
r
esen
ted
i
n
t
h
is
p
ap
er
,
i.e
.
,
a
f
r
a
m
e
w
o
r
k
f
o
r
a
u
s
er
-
f
r
ien
d
l
y
V
NF
m
o
d
eli
n
g
th
at
d
ev
e
lo
p
er
s
ca
n
u
s
e
to
p
r
o
v
id
e
a
f
o
r
m
al
d
escr
ip
tio
n
o
f
t
h
eir
f
u
n
ctio
n
s
to
b
e
u
s
ed
in
a
v
er
if
icatio
n
p
r
o
ce
s
s
.
T
h
e
m
aj
o
r
h
ig
h
li
g
h
t o
f
o
u
r
f
r
a
m
e
w
o
r
k
i
s
its
s
i
m
p
lici
t
y
a
n
d
w
e
d
ev
elo
p
it tar
g
e
tin
g
t
h
r
ee
s
p
ec
if
ic
o
b
j
ec
tiv
es:
-
T
o
s
i
m
p
li
f
y
t
h
e
d
ef
i
n
itio
n
o
f
a
n
et
w
o
r
k
f
u
n
ctio
n
f
o
r
w
ar
d
in
g
m
o
d
el
i
n
a
w
ell
-
k
n
o
w
n
lan
g
u
a
g
e.
-
T
o
leav
e
s
o
m
e
g
en
er
al
co
n
ce
p
ts
an
d
f
le
x
ib
ilit
y
to
d
ev
elo
p
er
s
in
s
u
ch
a
w
a
y
th
a
t
t
h
e
y
c
o
u
ld
d
ef
i
n
e
t
h
e
d
esire
d
b
eh
av
io
r
f
o
r
all
th
eir
n
et
w
o
r
k
f
u
n
ct
io
n
s
.
-
T
o
p
r
o
v
id
e
an
au
to
m
atic
tr
an
s
latio
n
f
r
o
m
t
h
e
f
u
n
c
tio
n
m
o
d
e
l
d
ef
in
itio
n
in
to
an
ab
s
tr
ac
t
f
o
r
m
al
m
o
d
el
f
o
r
v
er
if
ica
tio
n
to
o
ls
.
I
n
o
r
d
er
to
m
ee
t
t
h
e
ab
o
v
e
-
m
en
tio
n
ed
p
r
in
cip
le
s
,
w
e
s
elec
t
J
av
a
as
a
w
ell
-
k
n
o
w
n
a
n
d
w
id
e
s
p
r
ea
d
lan
g
u
a
g
e
th
a
t
d
ev
e
lo
p
er
s
f
i
n
d
s
i
m
p
le
a
n
d
ea
s
y
to
g
r
a
s
p
.
T
h
e
s
p
ec
if
ic
lib
r
ar
y
w
e
p
r
o
p
o
s
e
in
th
is
J
av
a
-
b
ased
f
r
a
m
e
w
o
r
k
r
ep
r
esen
ts
t
h
e
t
y
p
ical
s
et
o
f
h
i
g
h
-
le
v
el
o
p
er
atio
n
s
co
m
m
o
n
l
y
u
s
ed
f
o
r
d
escr
ib
in
g
t
h
e
n
e
t
w
o
r
k
f
u
n
ctio
n
’
s
b
eh
a
v
io
r
.
Star
tin
g
f
r
o
m
a
s
k
ele
to
n
clas
s
d
ef
i
n
it
io
n
o
f
a
g
e
n
er
ic
n
et
w
o
r
k
f
u
n
ctio
n
,
a
VNF
d
ev
elo
p
er
ca
n
ea
s
il
y
e
x
te
n
d
th
e
p
r
o
v
id
ed
ar
tif
ac
ts
to
in
h
er
it
b
asic
p
r
o
p
er
ties
,
d
ata
ty
p
es,
an
d
m
et
h
o
d
s
an
d
cu
s
to
m
ize
f
u
n
ctio
n
b
eh
a
v
io
r
.
Ou
r
f
r
a
m
e
w
o
r
k
also
i
n
cl
u
d
es
a
p
ar
s
er
t
h
at
an
al
y
ze
s
th
e
J
av
a
s
o
u
r
ce
co
d
e
an
d
p
r
o
d
u
ce
s
an
ab
s
tr
ac
t
f
o
r
m
al
m
o
d
el
o
f
t
h
e
n
et
w
o
r
k
f
u
n
ctio
n
t
h
at
ca
n
b
e
au
to
m
at
icall
y
tr
an
s
lated
in
to
t
h
e
in
p
u
t
la
n
g
u
a
g
e
p
r
o
p
er
o
f
a
g
iv
en
v
er
i
f
icatio
n
to
o
l.
T
h
is
s
ec
o
n
d
s
tep
is
clea
r
l
y
to
o
l
d
ep
en
d
en
t
an
d
w
e
p
lan
to
en
r
ich
o
u
r
f
r
a
m
e
w
o
r
k
in
o
r
d
er
to
s
u
p
p
o
r
t
th
e
v
as
t
m
aj
o
r
it
y
o
f
th
e
e
x
is
t
in
g
to
o
ls
.
C
u
r
r
en
tl
y
,
th
e
p
ar
s
er
o
p
e
r
atio
n
is
o
r
ien
ted
to
f
o
r
m
al
v
er
i
f
ica
tio
n
to
o
ls
b
ased
o
n
th
e
a
n
al
y
s
i
s
o
f
l
o
g
ic
f
o
r
m
u
las
an
d
in
p
ar
ticu
lar
th
e
Ver
iGr
ap
h
[
6
]
to
o
l
is
ad
o
p
ted
as
a
u
s
e
ca
s
e.
Ver
ig
r
ap
h
r
eq
u
ir
es
to
m
o
d
el
co
m
p
lex
n
et
w
o
r
k
s
ce
n
ar
io
s
a
s
s
ets
o
f
First
Or
d
er
L
o
g
ic
(
F
OL
)
f
o
r
m
u
la
s
a
n
d
u
s
es
an
S
MT
s
o
lv
er
,
Z
3
[
7
]
,
to
v
er
i
f
y
s
atis
f
iab
ilit
y
o
f
t
h
es
e
f
o
r
m
u
las.
W
e
h
e
n
ce
d
e
v
elo
p
ed
a
tr
an
s
lato
r
f
o
r
co
n
v
er
ti
n
g
t
h
e
o
u
tp
u
t
o
f
th
e
p
ar
s
er
to
t
h
e
p
r
o
p
er
s
et
o
f
FO
L
f
o
r
m
u
las.
T
o
ch
ec
k
th
e
co
r
r
ec
tn
es
s
o
f
t
h
e
m
o
d
els
o
b
tai
n
e
d
,
th
e
d
e
v
elo
p
er
ca
n
r
u
n
te
s
t
s
to
v
er
if
y
n
et
w
o
r
k
p
r
o
p
er
ties
in
ter
m
s
o
f
r
ea
ch
ab
ilit
y
b
et
w
ee
n
d
i
f
f
er
e
n
t
n
o
d
es
in
s
ev
er
al
s
i
m
p
le
g
r
ap
h
s
th
at
i
n
clu
d
e
t
h
e
d
ev
elo
p
ed
VNF
m
o
d
el.
W
e
f
ir
s
t
in
tr
o
d
u
ce
o
u
r
m
o
d
eli
n
g
tech
n
iq
u
e
i
n
Sec
tio
n
3
.
T
h
e
u
s
e
ca
s
e
an
d
t
h
e
o
b
tain
ed
r
esu
lt
s
ar
e
p
r
esen
ted
in
Sec
tio
n
4
.
I
n
ad
d
itio
n
,
Se
ctio
n
2
d
is
cu
s
s
e
s
r
elate
d
w
o
r
k
,
w
h
ile
Sect
io
n
5
co
n
clu
d
es t
h
e
p
ap
er
.
2.
RE
L
AT
E
D
WO
RK
T
h
er
e
h
as
b
ee
n
a
s
ig
n
i
f
ica
n
t
a
m
o
u
n
t
o
f
ac
ti
v
it
y
i
n
t
h
e
p
ast
y
ea
r
s
o
n
atte
m
p
t
in
g
to
p
r
o
v
id
e
a
p
r
o
p
er
s
u
p
p
o
r
t
f
o
r
th
e
tr
an
s
latio
n
o
f
s
o
f
t
w
ar
e
s
y
s
te
m
d
escr
ip
tio
n
s
t
o
th
e
i
n
p
u
t
m
o
d
els
f
o
r
v
er
i
f
ic
atio
n
to
o
ls
.
Am
o
n
g
th
e
o
th
er
s
,
w
e
ca
n
m
e
n
tio
n
B
an
d
er
a
[
8
]
an
d
J
av
aP
ath
Fin
d
er
[
9
]
.
T
h
e
t
w
o
ap
p
r
o
ac
h
es
ar
e
b
ased
o
n
m
o
d
el
ch
ec
k
i
n
g
,
an
d
th
e
m
o
d
els
th
e
y
e
x
tr
ac
t
ar
e
m
o
d
els
o
f
J
av
a
s
o
f
t
w
ar
e.
T
h
e
m
ai
n
d
if
f
er
e
n
ce
w
it
h
r
esp
ec
t
to
th
e
p
r
o
p
o
s
ed
f
r
a
m
e
w
o
r
k
is
t
h
at
th
e
y
co
n
s
id
er
g
e
n
er
al
-
p
u
r
p
o
s
e
J
av
a
p
r
o
g
r
am
s
a
n
d
th
eir
m
ai
n
tar
g
et
i
s
t
h
e
id
en
ti
f
icatio
n
o
f
p
r
o
g
r
a
m
m
i
n
g
er
r
o
r
s
an
d
b
u
g
s
.
Her
e
i
n
s
tead
w
e
d
ea
l
w
i
th
t
h
e
f
o
r
w
ar
d
i
n
g
b
eh
av
io
r
o
f
VN
Fs
.
W
e
ar
e
n
o
t
in
ter
ested
in
all
th
e
d
etails
o
f
th
e
VNF
co
d
e
ex
ec
u
tio
n
.
F
u
r
th
er
m
o
r
e,
w
e
w
an
t
o
u
r
an
al
y
s
i
s
to
b
e
ex
tr
e
m
e
l
y
f
ast.
Mo
r
eo
v
er
,
m
a
n
y
ap
p
r
o
ac
h
es
a
n
d
m
et
h
o
d
s
f
o
r
s
tatic
n
et
w
o
r
k
an
al
y
s
is
h
av
e
b
ee
n
p
r
o
p
o
s
ed
[2
,
5
,
1
0
]
.
Net
w
o
r
k
Op
ti
m
ized
Data
lo
g
[
2
]
r
elies
o
n
Data
lo
g
b
o
th
f
o
r
n
et
w
o
r
k
m
o
d
els
an
d
p
o
licy
co
n
s
tr
ain
ts
.
B
UZ
Z
[
1
0
]
u
s
es h
a
n
d
-
g
e
n
er
at
ed
m
o
d
els o
f
n
et
w
o
r
k
f
u
n
ctio
n
s
in
a
d
o
m
ai
n
s
p
ec
i
f
ic
la
n
g
u
a
g
e.
A
s
w
e
d
i
s
cu
s
s
ed
ea
r
lier
,
m
o
d
elin
g
n
e
t
w
o
r
k
f
u
n
ctio
n
alit
y
f
o
r
u
s
in
g
th
e
s
e
to
o
ls
is
d
if
f
ic
u
lt
a
n
d
r
eq
u
ir
es
a
d
etailed
u
n
d
er
s
ta
n
d
in
g
o
f
th
e
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eq
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o
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n
f
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cr
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a
m
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el
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at
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p
t
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r
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ll c
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ath
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o
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w
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ch
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s
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th
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s
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to
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tain
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ter
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ith
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la
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g
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ap
p
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th
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li
m
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o
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th
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h
es
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ased
o
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t
h
e
ex
tr
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m
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s
f
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s
o
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t
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at
t
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m
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s
is
t
y
p
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ca
ll
y
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y
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n
s
tead
o
f
r
el
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in
g
o
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v
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d
o
r
s
to
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elea
s
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t
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co
d
e,
th
e
ai
m
o
f
o
u
r
f
r
a
m
e
w
o
r
k
i
s
to
g
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v
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d
ev
elo
p
er
s
th
e
o
p
p
o
r
tu
n
it
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to
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m
p
le
m
e
n
t
t
h
eir
n
et
w
o
r
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f
u
n
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s
r
ese
m
b
li
n
g
as
m
u
c
h
as
p
o
s
s
ib
le
th
e
r
ea
l
o
n
e’
s
b
eh
av
io
r
.
3.
M
O
DE
L
I
N
G
T
E
CH
N
I
Q
U
E
C
u
r
r
en
t
l
y
,
th
er
e
i
s
n
o
s
ta
n
d
ar
d
o
r
m
o
d
elin
g
la
n
g
u
a
g
e
to
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cu
r
atel
y
r
ep
r
esen
t
t
h
e
d
i
v
e
r
s
it
y
a
n
d
co
m
p
le
x
it
y
o
f
n
et
w
o
r
k
f
u
n
cti
o
n
s
.
Mo
s
t
o
f
th
e
r
e
s
ea
r
ch
e
f
f
o
r
ts
i
n
p
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p
o
s
in
g
V
NF
m
o
d
els
ar
e
f
o
c
u
s
ed
o
n
n
et
w
o
r
k
v
er
i
f
icatio
n
an
d
g
ai
n
ed
p
o
p
u
lar
it
y
in
t
h
e
v
er
i
f
icati
o
n
co
m
m
u
n
it
y
.
I
n
t
h
is
s
ec
tio
n
,
w
e
li
s
t
th
e
o
p
en
p
r
o
b
lem
s
t
h
at
w
e
h
a
v
e
e
n
co
u
n
ter
ed
w
h
i
le
lo
o
k
in
g
at
t
h
e
p
r
o
p
o
s
ed
VNF
m
o
d
els in
t
h
e
v
er
i
f
icatio
n
co
n
te
x
t.
3
.
1
.
O
v
er
v
ie
w
a
nd
pro
ble
m
s
t
a
t
em
e
nt
Mo
d
elin
g
o
f
VNF
s
is
u
s
ef
u
l
in
a
n
u
m
b
er
o
f
w
a
y
s
r
an
g
in
g
f
r
o
m
f
i
n
d
in
g
s
ca
lab
ilit
y
i
s
s
u
es
i
n
ap
p
licatio
n
s
to
f
in
d
i
n
g
n
et
wo
r
k
co
n
f
i
g
u
r
atio
n
b
u
g
s
,
in
p
ar
ticu
lar
b
y
m
ea
n
s
o
f
f
o
r
m
a
l
v
er
if
icatio
n
to
o
ls
.
Ho
w
e
v
er
,
f
o
r
m
al
m
o
d
eli
n
g
o
f
n
et
w
o
r
k
f
u
n
ct
io
n
alit
ies
i
s
d
if
f
ic
u
lt
a
n
d
r
eq
u
ir
es
a
d
etailed
u
n
d
er
s
tan
d
i
n
g
o
f
t
h
e
s
p
ec
if
ic
v
er
i
f
icatio
n
to
o
l’
s
in
ter
n
als,
s
e
m
a
n
tic
s
,
an
d
m
o
d
elin
g
la
n
g
u
a
g
e.
W
ith
t
h
i
s
r
es
p
ec
t,
an
au
to
m
ated
ap
p
r
o
ac
h
to
g
en
er
ate
m
o
d
els
e
li
m
i
n
ate
s
th
e
n
ec
es
s
it
y
o
f
h
a
v
i
n
g
d
etailed
k
n
o
w
led
g
e
in
t
h
e
f
o
r
m
al
v
er
i
f
icatio
n
d
o
m
ai
n
a
n
d
h
elp
s
e
n
g
i
n
ee
r
s
to
q
u
ick
l
y
d
eter
m
i
n
e
t
h
e
b
eh
a
v
i
o
r
o
f
a
VNF
-
b
ased
n
et
w
o
r
k
,
s
t
ar
tin
g
f
r
o
m
a
m
o
r
e
u
s
er
-
f
r
ie
n
d
l
y
d
escr
ip
tio
n
o
f
th
e
in
v
o
lv
ed
VNF
s
.
I
n
p
ar
ticu
la
r
,
th
e
p
o
s
s
ib
ilit
y
to
d
escr
ib
e
V
NFs
b
y
m
ea
n
s
o
f
a
J
av
a
-
li
k
e
m
o
d
eli
n
g
la
n
g
u
a
g
e
w
o
u
l
d
s
i
g
n
if
ica
n
tl
y
lo
w
er
b
ar
r
ier
s
to
en
tr
y
f
o
r
th
e
s
e
p
o
w
er
f
u
l
v
er
if
icatio
n
ap
p
r
o
ac
h
es.
An
i
m
p
er
ati
v
e
la
n
g
u
a
g
e
s
u
c
h
as
J
av
a
f
o
cu
s
es
o
n
d
escr
i
b
in
g
h
o
w
a
p
r
o
g
r
a
m
o
p
er
ates.
A
VN
F
d
ev
elo
p
er
ca
n
w
r
ite
a
co
d
e
th
at
d
escr
ib
es
in
ex
ac
t
d
etail
t
h
e
s
tep
s
th
at
t
h
e
VNF
m
u
s
t
m
a
k
e
w
h
en
a
p
ac
k
et
i
s
r
ec
eiv
ed
f
r
o
m
o
n
e
o
f
its
i
n
ter
f
ac
es.
I
n
co
n
tr
ast,
d
ec
lar
a
tiv
e
lan
g
u
ag
e
s
ad
o
p
ted
in
l
o
g
ic
-
b
ased
f
o
r
m
a
l
v
er
if
ica
tio
n
to
o
ls
d
o
n
o
t sp
ec
if
y
a
s
tep
o
r
s
eq
u
en
ce
o
f
s
tep
s
t
o
ex
ec
u
te,
b
u
t r
at
h
er
p
r
ed
icate
s
th
at
m
u
s
t
h
o
ld
.
T
h
e
co
n
ce
p
tu
al
g
ap
b
et
w
ee
n
th
e
s
e
t
w
o
r
ep
r
ese
n
tatio
n
s
i
s
th
e
i
m
p
o
r
tan
t
c
h
alle
n
g
e
s
o
l
v
ed
b
y
o
u
r
ap
p
r
o
ac
h
.
T
h
e
p
r
o
p
o
s
ed
f
r
am
e
w
o
r
k
p
r
o
v
id
es
a
J
a
v
a
lib
r
ar
y
an
d
a
p
ar
s
er
.
T
h
e
lib
r
ar
y
ca
n
b
e
u
s
ed
f
o
r
m
o
d
eli
n
g
n
et
w
o
r
k
f
u
n
ctio
n
s
b
y
m
ea
n
s
o
f
an
i
m
p
er
ati
v
e
lan
g
u
a
g
e.
T
h
e
p
ar
s
er
th
en
au
to
m
atica
ll
y
g
e
n
er
ates
ab
s
tr
ac
tio
n
m
o
d
els
f
r
o
m
t
h
ese
d
escr
ip
tio
n
s
.
B
asicall
y
,
th
e
p
a
r
s
er
tak
es
as
a
n
i
n
p
u
t
t
h
e
d
ef
in
itio
n
w
r
itte
n
u
s
i
n
g
o
u
r
lib
r
ar
y
a
n
d
p
r
o
d
u
ce
s
an
ab
s
tr
ac
t
f
o
r
m
al
m
o
d
el
d
es
cr
ib
in
g
t
h
e
b
e
h
a
v
io
r
o
f
th
e
n
et
w
o
r
k
f
u
n
ctio
n
.
T
h
is
g
iv
e
s
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3
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2
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O
v
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pro
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t
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T
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v
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t
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al
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ctio
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B
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W
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Evaluation Warning : The document was created with Spire.PDF for Python.
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lib
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cla
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b
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h
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f
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llo
w
in
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c
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ac
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is
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w
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w
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est).
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A
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p
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b
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lib
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p
ac
k
et.
T
h
e
p
ar
am
et
er
o
f
th
e
o
n
R
ec
ei
v
ed
P
ac
k
et(
)
m
et
h
o
d
is
th
e
p
ac
k
et
t
h
at
t
h
e
n
et
w
o
r
k
f
u
n
ctio
n
r
ec
eiv
es
a
n
d
th
e
r
etu
r
n
v
a
l
u
e
is
a
R
o
u
ti
n
g
R
e
s
u
l
t
o
b
j
e
ct.
As
d
is
cu
s
s
ed
ab
o
v
e,
R
o
u
tin
g
R
es
u
lt
is
a
co
m
p
le
m
e
n
tar
y
cla
s
s
t
h
at
r
e
p
r
esen
ts
t
h
e
r
o
u
ti
n
g
d
ec
i
s
io
n
o
f
th
e
VN
F,
af
ter
p
r
o
ce
s
s
i
n
g
o
f
t
h
e
in
co
m
i
n
g
p
ac
k
et.
I
ts
co
n
s
tr
u
cto
r
r
ec
eiv
e
s
th
r
ee
p
ar
a
m
eter
s
:
-
A
p
ac
k
et
o
b
j
ec
t th
at
t
h
e
n
et
w
o
r
k
f
u
n
ct
io
n
p
r
o
d
u
ce
s
.
-
T
h
e
ac
tio
n
to
p
er
f
o
r
m
o
n
t
h
is
p
ac
k
et
(
f
o
r
w
ar
d
o
r
d
r
o
p
)
.
-
T
h
e
f
o
r
w
ar
d
in
g
d
ir
ec
tio
n
(
i.e
.
th
e
in
ter
f
ac
e
th
e
p
ac
k
et
is
f
o
r
w
ar
d
ed
to
in
ca
s
e
o
f
f
o
r
w
ar
d
ac
tio
n
;
th
is
ca
n
b
e
th
e
u
p
s
tr
ea
m
in
ter
f
ac
e
o
r
o
n
e
o
f
t
h
e
o
th
er
in
ter
f
ac
es o
f
th
e
n
et
w
o
r
k
f
u
n
ctio
n
)
.
T
h
e
ac
tio
n
s
t
h
at
ca
n
b
e
in
s
er
ted
in
s
id
e
t
h
is
m
et
h
o
d
ar
e
d
iv
id
ed
in
to
t
h
e
f
o
llo
w
in
g
ca
teg
o
r
ies:
in
s
tr
u
ctio
n
s
to
ch
ec
k
t
h
e
co
n
t
en
ts
o
f
a
p
ac
k
et
f
ield
,
in
s
tr
u
c
tio
n
s
to
ch
ec
k
t
h
e
s
tate
o
f
th
e
n
et
w
o
r
k
f
u
n
ctio
n
,
in
s
tr
u
ctio
n
s
to
s
to
r
e
a
v
a
lu
e
in
to
a
tab
le
d
ef
in
ed
b
y
t
h
e
u
s
er
,
in
s
tr
u
ctio
n
s
to
d
ef
in
e
th
e
ac
tio
n
to
b
e
p
er
f
o
r
m
ed
o
n
a
p
ac
k
et
(
th
r
o
u
g
h
a
R
o
u
ti
n
g
R
e
s
u
lt),
an
d
s
etti
n
g
a
v
al
u
e
i
n
to
a
f
ield
o
f
a
p
ac
k
et.
An
e
x
a
m
p
le
o
f
t
h
e
J
av
a
d
escr
ip
tio
n
o
f
a
n
An
tis
p
a
m
n
et
w
o
r
k
f
u
n
ctio
n
is
s
h
o
w
n
i
n
Fi
g
u
r
e
1
.
T
h
is
is
an
in
ter
m
ed
iar
y
VNF
d
esi
g
n
e
d
to
h
an
d
le
th
e
m
ail
tr
af
f
ic
b
e
t
w
ee
n
en
d
h
o
s
ts
o
n
th
e
b
asi
s
o
f
a
b
lack
lis
t
tab
le.
T
h
e
n
a
m
e
o
f
th
e
tab
le,
n
u
m
b
e
r
o
f
co
lu
m
n
s
ass
ig
n
ed
f
o
r
t
h
is
tab
le
an
d
th
e
t
y
p
e
o
f
t
h
e
tab
l
e
en
tr
ies
ar
e
p
ass
ed
as
an
ar
g
u
m
e
n
t
to
th
e
c
o
n
s
tr
u
c
to
r
o
f
th
e
Ho
s
tT
ab
le
class
in
th
e
d
ef
i
n
eState(
)
m
et
h
o
d
(
r
o
w
2
,
Fig
u
r
e
1
)
.
I
n
th
i
s
s
ce
n
ar
io
,
th
e
tab
le
n
a
m
ed
“
B
lack
lis
t”
co
n
tai
n
in
g
a
s
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c
o
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m
n
to
s
to
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th
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ted
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m
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e
s
w
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t
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p
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u
m
Field
T
y
p
e.
M
A
I
L
FR
O
M
i
s
c
r
ea
ted
.
W
h
er
ea
s
t
h
e
f
o
r
w
ar
d
i
n
g
b
eh
a
v
io
r
o
f
t
h
e
An
ti
s
p
a
m
V
NF
i
s
d
escr
ib
ed
u
s
in
g
t
h
e
o
n
R
ec
ei
v
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P
ac
k
et(
)
m
et
h
o
d
.
I
n
p
ar
ticu
lar
,
li
n
es
6
an
d
7
d
escr
ib
e
th
e
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
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&
C
o
m
p
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n
g
I
SS
N:
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8
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V
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mo
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g
a
p
p
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r
ve
r
ifica
tio
n
p
u
r
p
o
s
es (
Gu
id
o
Ma
r
ch
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)
2631
f
o
r
w
ar
d
i
n
g
ac
tio
n
if
t
h
e
p
r
o
to
co
l
o
f
t
h
e
r
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eiv
ed
p
ac
k
et
i
s
e
q
u
al
to
a
P
OP
3
r
eq
u
est.
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f
th
is
is
n
o
t
t
h
e
ca
s
e
an
d
th
e
p
r
o
to
co
l
o
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th
e
p
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k
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al
to
a
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OP3
r
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o
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s
e,
th
en
th
e
m
ail
s
o
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r
ce
f
ield
o
f
t
h
e
p
ac
k
et
m
u
s
t
b
e
ch
ec
k
ed
a
g
ai
n
s
t
b
lac
k
lis
t
en
tr
ies
as
s
h
o
w
n
i
n
li
n
es
9
a
n
d
1
0
.
I
f
th
e
m
ail
s
o
u
r
ce
f
ield
o
f
th
e
P
OP
3
r
eq
u
est
p
ac
k
et
d
o
es
n
o
t
m
atc
h
a
n
y
ta
b
le
en
tr
y
,
t
h
e
n
th
e
n
e
w
R
o
u
ti
n
g
R
es
u
lt
o
b
j
ec
t
m
u
s
t
b
e
r
et
u
r
n
ed
s
p
ec
i
f
y
in
g
t
h
e
f
o
r
w
ar
d
i
n
g
ac
tio
n
(
lin
e
1
1
)
.
Fin
all
y
,
l
in
e
1
3
co
r
r
esp
o
n
d
s
to
a
d
r
o
p
ac
tio
n
th
a
t
m
u
s
t
b
e
en
f
o
r
ce
d
b
y
t
h
e
n
et
w
o
r
k
f
u
n
ctio
n
,
in
ca
s
e
o
f
n
o
o
th
er
co
n
d
itio
n
s
ar
e
m
et.
I
t
is
i
m
p
o
r
tan
t
to
m
e
n
tio
n
t
h
at
th
er
e
is
n
o
t
an
y
r
estrictio
n
o
n
th
e
o
r
d
er
o
f
p
ac
k
et
p
r
o
ce
s
s
in
g
ac
tio
n
s
p
er
f
o
r
m
ed
in
s
id
e
th
e
o
n
R
ec
e
iv
ed
P
ac
k
et(
)
m
et
h
o
d
,
as
th
is
is
h
a
n
d
led
ac
co
r
d
in
g
l
y
b
y
th
e
p
ar
s
er
.
Fig
u
r
e
1
.
J
av
a
d
escr
ip
tio
n
o
f
th
e
b
eh
av
io
r
o
f
th
e
An
tis
p
a
m
n
et
w
o
r
k
f
u
n
ct
io
n
i
n
r
esp
o
n
s
e
to
a
r
ec
eiv
ed
p
ac
k
et
3
.
3
.
P
a
rser
On
e
o
f
t
h
e
m
o
s
t
i
m
p
o
r
tan
t
asp
ec
ts
o
f
o
u
r
ap
p
r
o
ac
h
is
th
e
p
ar
s
er
th
at
an
al
y
s
e
s
th
e
u
s
er
clas
s
d
escr
ib
in
g
t
h
e
v
ir
t
u
al
n
et
w
o
r
k
f
u
n
ctio
n
.
T
h
e
p
ar
s
er
o
p
er
a
tin
g
p
r
in
cip
les
clea
r
l
y
d
ep
en
d
o
n
th
e
ad
o
p
ted
v
er
if
ica
tio
n
to
o
l.
A
s
s
aid
ab
o
v
e,
th
is
p
ap
er
co
n
s
id
er
s
lo
g
ic
-
b
ased
to
o
ls
.
T
h
e
r
est o
f
t
h
is
s
ec
tio
n
is
th
e
n
f
o
cu
s
ed
o
n
t
h
is
ap
p
r
o
ac
h
,
b
u
t
s
i
m
ilar
s
o
lu
tio
n
s
m
i
g
h
t
b
e
ap
p
lied
to
d
ef
i
n
e
p
ar
s
i
n
g
p
r
o
ce
s
s
es
t
h
at
ar
e
s
u
itab
le
f
o
r
o
th
er
f
o
r
m
al
v
er
if
ica
tio
n
tec
h
n
iq
u
es
.
T
h
is
is
p
ar
t
o
f
o
u
r
o
n
g
o
in
g
wo
r
k
an
d
w
e
p
la
n
to
h
av
e
a
w
id
er
to
o
l
co
v
er
ag
e
in
a
n
ea
r
f
u
tu
r
e.
T
h
e
m
ai
n
f
u
n
ctio
n
alitie
s
o
f
t
h
e
p
ar
s
er
in
th
is
f
r
a
m
e
w
o
r
k
ar
e
th
e
f
o
llo
w
i
n
g
:
-
th
e
id
en
ti
f
icat
io
n
o
f
t
h
e
i
n
s
tr
u
ctio
n
s
i
n
th
e
J
av
a
co
d
e
th
at
lea
d
to
a
p
ac
k
et
b
ein
g
s
en
t th
r
o
u
g
h
an
i
n
ter
f
ac
e
;
-
th
e
id
en
ti
f
icatio
n
o
f
th
e
co
n
d
i
tio
n
s
(
I
F
s
tate
m
en
ts
)
th
at
ar
e
tr
av
er
s
ed
to
r
ea
ch
th
e
ab
o
v
e
m
en
tio
n
ed
s
e
n
d
in
s
tr
u
ctio
n
s
.
I
n
o
th
er
w
o
r
d
s
,
w
e
n
ee
d
to
id
en
ti
f
y
all
th
e
co
n
d
itio
n
s
t
h
at
t
r
ig
g
er
a
p
ac
k
et
s
e
n
d
in
g
o
p
er
at
io
n
,
w
h
ich
is
ac
t
u
all
y
w
h
a
t
d
ef
i
n
es
th
e
b
eh
av
io
r
o
f
a
n
et
w
o
r
k
f
u
n
cti
o
n
.
W
e
p
ar
s
e
th
e
s
o
u
r
ce
co
d
e
to
co
n
v
er
t
t
h
ese
co
n
d
itio
n
s
i
n
to
a
s
p
ec
if
ic
d
ata
s
tr
u
ctu
r
e,
co
n
s
id
er
i
n
g
b
o
th
th
e
f
ield
s
o
f
t
h
e
p
ac
k
ets
t
h
at
tr
av
er
s
e
th
e
f
u
n
ctio
n
an
d
th
e
f
u
n
ctio
n
s
tat
u
s
,
i
f
an
y
.
I
n
o
r
d
er
to
d
eliv
er
th
e
af
o
r
e
m
e
n
tio
n
ed
f
u
n
ctio
n
alitie
s
,
w
e
tak
e
ad
v
an
ta
g
e
o
f
E
clip
s
e
AST
AP
I
[
1
5
]
in
th
e
e
x
tr
ac
tio
n
p
r
o
ce
s
s
f
r
o
m
s
o
u
r
ce
co
d
e
to
a
d
ata
s
tr
u
ct
u
r
e
.
I
t
is
a
to
o
l
t
h
at
ca
n
g
e
n
er
ate
an
A
b
s
tr
ac
t
S
y
n
tax
T
r
ee
(
A
ST
)
[
1
6
]
r
ep
r
esen
tatio
n
o
f
ex
i
s
ti
n
g
J
av
a
s
o
u
r
ce
co
d
e.
A
ST
is
a
r
ep
r
esen
tatio
n
o
f
a
g
r
ap
h
in
th
e
f
o
r
m
o
f
a
tr
ee
f
r
o
m
ab
s
tr
ac
t s
y
n
tac
ti
c
s
tr
u
ct
u
r
e
o
f
co
d
e.
Usi
n
g
t
h
i
s
lib
r
ar
y
,
o
u
r
p
ar
s
er
is
ab
le
to
r
e
p
r
esen
t e
v
er
y
J
av
a
f
ile
a
s
a
tr
ee
o
f
AST
n
o
d
es.
T
h
is
s
tep
h
elp
s
to
p
er
f
o
r
m
a
s
e
m
a
n
tic
a
n
al
y
s
i
s
u
s
i
n
g
th
e
i
n
f
o
r
m
atio
n
in
ea
c
h
n
o
d
e,
w
h
er
e
all
t
h
ese
n
o
d
es
a
r
e
s
p
ec
ialized
f
o
r
th
e
s
y
m
b
o
li
c
ev
en
t
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J
av
a
p
r
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m
i
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r
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er
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o
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o
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e.
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ar
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r
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i
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it
s
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ST
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t
h
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co
d
e
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d
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to
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ca
l
v
ar
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all
t
h
e
ch
ar
ac
t
er
is
tics
s
u
c
h
as:
m
et
h
o
d
d
ec
lar
atio
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s
,
v
ar
iab
les,
co
n
d
itio
n
s
,
r
etu
r
n
p
r
ed
icate
s
,
an
d
s
tate
m
e
n
ts
.
A
l
ter
n
ati
v
el
y
,
th
e
p
ar
s
er
tak
e
s
a
“
s
n
ap
s
h
o
t”
o
f
th
e
c
u
r
r
en
t
d
e
f
i
n
itio
n
o
f
t
h
e
n
et
w
o
r
k
f
u
n
ct
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an
d
p
r
o
ce
ed
s
in
g
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ati
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g
t
h
e
f
i
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al
m
o
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el
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ter
m
s
o
f
h
i
g
h
-
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v
el
lo
g
ical
ex
p
r
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io
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s
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T
h
e
f
in
al
m
o
d
el
is
m
o
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a
ted
b
y
th
e
v
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s
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o
f
Op
en
Flo
w
[
1
7
]
f
o
r
w
ar
d
in
g
ab
s
tr
ac
tio
n
o
f
t
h
e
f
o
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m
<
m
a
tch
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ctio
n
>
.
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h
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ab
s
tr
ac
tio
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m
o
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el
h
a
s
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ee
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b
o
r
r
o
w
ed
f
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m
t
h
e
e
x
is
tin
g
m
o
d
eli
n
g
tec
h
n
iq
u
e
s
[
1
1
,
1
8
]
an
d
m
o
s
t
o
f
t
h
e
v
er
if
ica
tio
n
to
o
ls
o
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f
o
r
w
ar
d
i
n
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b
eh
av
io
r
[
5
,
6
,
1
9
]
r
ely
o
n
t
h
e
m
o
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els ad
h
er
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t
h
is
ab
s
tr
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l
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p
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ce
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ta
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a
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ex
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s
tep
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th
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ar
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o
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s
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o
r
e
an
d
af
ter
th
e
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m
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⇒
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ig
n
.
T
h
e
f
o
llo
w
i
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g
r
u
les s
er
v
e
as a
g
u
id
eli
n
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to
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s
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B
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th
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t
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s
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co
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s
id
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tim
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n
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s
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cr
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.
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b
e
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t
h
er
co
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s
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f
ter
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s
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.
T
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a
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in
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h
ich
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m
e
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o
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th
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.
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,
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f
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f
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p
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if
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if
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O
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w
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tl
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tr
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Ver
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d
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cu
s
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ed
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th
e
f
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llo
w
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g
.
4.
USE
CA
SE
AN
D
RE
SUL
T
S
4
.
1
.
T
ra
ns
la
t
io
n pa
t
t
er
n.
Ver
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r
a
ph
(
Z
3
)
Am
o
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g
t
h
e
ex
is
ti
n
g
lo
g
ic
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b
as
ed
v
er
if
icatio
n
to
o
ls
,
w
e
s
elec
ted
Ver
iGr
ap
h
[
6
]
as
a
u
s
e
ca
s
e
to
s
h
o
w
h
o
w
th
e
m
o
d
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ated
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y
th
e
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ar
s
e
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n
b
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e
x
p
lo
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,
af
ter
p
r
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p
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tr
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s
latio
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,
b
y
a
r
e
al
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if
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l.
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f
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m
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v
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f
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to
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atica
ll
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k
s
b
y
c
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k
in
g
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tain
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t.
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m
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x
p
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as
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m
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las
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T
h
ese
f
o
r
m
u
la
s
ar
e
d
if
f
ic
u
lt
to
w
r
ite.
He
n
ce
,
it
ca
n
g
r
ea
tl
y
b
e
n
ef
it
f
r
o
m
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h
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atic
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s
.
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w
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A
T
,
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e,
f
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w
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l,
I
DS
a
n
d
s
o
o
n
)
th
at
s
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ts
f
r
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m
a
s
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to
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n
t
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esti
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r
esp
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s
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to
a
v
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eq
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a
m
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co
n
s
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ti
n
g
o
f
Fi
r
s
t
Or
d
er
L
o
g
ic
(
FO
L
)
f
o
r
m
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la
s
[
2
0
]
,
is
c
h
ec
k
ed
ag
a
in
s
t
t
h
e
p
r
o
v
id
ed
p
o
licies,
f
o
r
e
x
a
m
p
le
r
ea
ch
ab
ilit
y
p
r
o
p
er
ties
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n
t
w
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n
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d
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th
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w
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k
.
I
n
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m
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h
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v
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n
o
f
f
-
t
h
e
-
s
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lf
S
A
T
s
o
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er
(
Z
3
)
,
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h
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eter
m
in
e
s
w
h
e
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th
e
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ied
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m
p
le,
s
to
r
es
t
h
e
d
at
a
co
r
r
esp
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n
d
in
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to
th
e
B
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Y
f
ield
o
f
t
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e
p
ac
k
e
t.
I
f
t
h
e
p
r
o
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l
o
f
t
h
e
r
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ei
v
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p
ac
k
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al
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HT
T
P
R
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T
P
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SP
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t
h
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k
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p
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ased
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n
th
e
B
ODY
f
ield
o
f
th
e
p
ac
k
et.
T
h
e
p
r
esen
ce
o
f
an
en
tr
y
co
r
r
esp
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n
d
in
g
to
th
at
d
ata
in
th
e
tab
le
r
es
u
lts
i
n
a
d
r
o
p
ac
tio
n
o
f
t
h
e
p
ac
k
et.
I
n
ad
d
itio
n
,
t
h
is
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s
t
h
e
s
tr
u
ctu
r
e
o
f
th
e
co
d
e
o
f
I
DS
VNF
s
h
ar
e
in
co
m
m
o
n
w
i
th
An
ti
s
p
a
m
V
NF.
W
eb
Ser
v
er
VNF
ch
ec
k
s
i
f
t
h
e
p
r
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to
c
o
l
o
f
th
e
p
ac
k
et
i
s
HT
T
P
R
E
QUE
ST
,
cr
ea
tes
a
n
e
w
p
ac
k
et
b
y
co
p
y
i
n
g
all
t
h
e
f
ie
ld
s
o
f
th
e
r
ec
eiv
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p
ac
k
et.
T
h
e
s
o
u
r
ce
/d
esti
n
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I
P
an
d
p
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r
t
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e
s
s
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h
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k
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s
w
ap
p
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an
d
P
R
OT
OC
OL
f
ield
is
s
et
to
HT
T
P
R
E
SP
ONSE
.
A
n
alo
g
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,
Ma
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VN
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d
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in
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tio
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llo
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s
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m
e
s
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e
o
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W
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C
ac
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a
s
tatef
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VNF
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i
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t
w
o
co
lu
m
n
s
.
O
n
R
ec
ei
v
ed
P
ac
k
et
(
)
m
et
h
o
d
o
f
th
e
cla
s
s
co
m
p
r
is
e
s
f
o
u
r
f
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r
w
ar
d
in
g
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tio
n
s
.
T
h
e
f
ir
s
t
t
w
o
ac
t
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s
co
r
r
esp
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n
d
to
a
if
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an
c
h
w
h
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e
th
e
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ter
f
ac
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o
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t
h
e
ar
r
iv
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p
ac
k
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is
in
ter
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al.
I
f
t
h
e
P
R
OT
OC
OL
o
f
th
e
p
ac
k
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is
eq
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l
to
HT
T
P
R
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QUE
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d
th
e
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s
an
en
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m
atch
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h
e
r
eq
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ted
UR
L
,
t
h
e
f
o
r
w
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d
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n
g
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tio
n
is
tak
e
n
.
T
h
is
f
o
r
w
ar
d
in
g
ac
tio
n
is
p
er
f
o
r
m
ed
o
n
i
n
ter
n
al
in
ter
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w
it
h
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n
e
w
p
ac
k
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co
n
tai
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i
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g
t
h
e
r
eq
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d
w
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p
ag
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I
f
th
e
r
eq
u
ested
w
eb
p
ag
e
is
n
o
t
av
ailab
le
in
t
h
e
tab
le
o
f
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h
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V
NF,
th
e
o
r
i
g
in
al
p
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i
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w
ar
d
ed
th
r
o
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g
h
th
e
ex
ter
n
al
in
ter
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O
n
th
e
o
t
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er
h
an
d
,
th
e
n
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x
t
t
w
o
f
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b
r
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ch
an
d
w
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alter
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p
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Ho
w
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if
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h
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P
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OT
OC
O
L
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f
th
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p
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HT
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P
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SP
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NSE,
w
eb
co
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t o
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th
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p
ac
k
et
s
to
r
ed
in
th
e
tab
le
o
f
th
e
V
NF.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
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lec
&
C
o
m
p
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n
g
,
Vo
l.
9
,
No
.
4
,
A
u
g
u
s
t 2
0
1
9
:
2
6
2
7
-
2636
2634
Fire
w
a
ll
A
C
L
(
ac
ce
s
s
co
n
tr
o
l
lis
t)
en
ab
led
s
tatele
s
s
n
et
w
o
r
k
f
u
n
ctio
n
,
co
n
ta
in
s
tab
le
o
b
j
ec
t
ac
lT
ab
l
e
o
f
t
w
o
co
l
u
m
n
s
,
ch
ar
ac
ter
ize
d
b
y
t
y
p
e
Field
T
y
p
e.
I
P
SR
C
an
d
Field
T
y
p
e.
I
P
DE
ST
.
T
h
e
tab
le
ac
ts
as
a
“
b
lack
lis
t”
a
n
d
if
t
h
e
p
ac
k
et
r
e
ce
iv
ed
m
atc
h
es t
h
e
t
u
p
le
in
t
h
e
tab
le,
a
d
r
o
p
ac
tio
n
is
p
er
f
o
r
m
ed
.
NA
T
(
Net
w
o
r
k
A
d
d
r
ess
T
r
an
s
lato
r
)
-
en
ab
led
n
et
w
o
r
k
f
u
n
c
tio
n
d
iv
id
es
th
e
n
et
w
o
r
k
in
to
t
w
o
ar
ea
s
(
an
in
ter
n
al
ar
ea
an
d
a
n
ex
ter
n
al
o
n
e)
an
d
ap
p
lies
d
if
f
er
en
t
r
u
les
o
n
th
e
i
n
co
m
in
g
p
ac
k
e
ts
i
f
t
h
e
y
ar
e
r
ec
eiv
ed
f
r
o
m
t
h
e
i
n
ter
n
al
o
r
th
e
e
x
ter
n
al
i
n
ter
f
ac
e.
I
n
th
i
s
ca
s
e,
p
ac
k
ets
r
ec
ei
v
ed
f
r
o
m
t
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e
i
n
ter
n
a
l
No
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w
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P
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ess
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W
h
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p
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r
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m
th
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ter
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to
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l
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if
a
co
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tio
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y
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x
is
t
s
.
4
.
3
.
E
x
peri
m
e
nta
l r
esu
lt
s
I
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o
r
d
er
also
to
ch
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k
th
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tn
es
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o
f
th
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e
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ated
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i
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m
o
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el
s
,
w
e
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n
s
tr
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cted
a
s
et
o
f
n
et
w
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k
to
p
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lo
g
ies
co
n
tain
in
g
th
e
a
v
ai
lab
le
n
et
w
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k
f
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s
an
d
w
e
d
e
m
o
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s
tr
ate
a
n
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m
b
er
o
f
cu
s
to
m
test
s
o
n
t
h
e
s
elec
ted
v
er
i
f
icatio
n
to
o
l.
Ver
iGr
ap
h
ca
n
p
er
f
o
r
m
d
i
f
f
er
en
t
k
i
n
d
s
o
f
v
er
i
f
icatio
n
test
s
:
r
ea
ch
ab
ilit
y
,
w
h
ic
h
co
n
s
is
ts
i
n
ch
ec
k
i
n
g
i
f
at
leas
t
o
n
e
p
ac
k
et
ca
n
ar
r
iv
e
at
t
h
e
d
esti
n
at
io
n
f
r
o
m
t
h
e
s
o
u
r
ce
n
o
d
e,
an
d
is
o
latio
n
,
w
h
ic
h
co
n
s
i
s
ts
i
n
v
er
if
y
i
n
g
th
at
n
o
p
ac
k
et
f
lo
w
i
n
g
f
r
o
m
s
o
u
r
ce
to
d
esti
n
atio
n
p
ass
e
s
th
r
o
u
g
h
a
ce
r
tain
n
et
w
o
r
k
f
u
n
ctio
n
.
I
n
th
is
s
ec
t
io
n
,
w
e
co
n
s
id
er
r
ea
ch
ab
ilit
y
p
r
o
p
er
ties
.
T
h
e
o
v
er
all
n
et
w
o
r
k
’
s
b
eh
av
io
r
(
e.
g
.
,
ro
u
tin
g
tab
les,
m
id
d
leb
o
x
co
n
f
ig
u
r
atio
n
s
,
h
o
s
t
m
etad
ata,
etc.
)
an
d
th
e
n
et
w
o
r
k
to
p
o
lo
g
y
i
n
f
o
r
m
atio
n
ar
e
r
ep
r
esen
ted
as
a
s
e
t
o
f
ad
d
i
tio
n
al
F
OL
f
o
r
m
u
la
s
a
n
d
co
m
p
leted
w
it
h
o
th
er
f
o
r
m
u
la
s
th
at
e
x
p
r
ess
th
e
p
r
o
p
er
ties
to
b
e
v
er
if
ied
(
e.
g
.
,
a
r
ea
ch
ab
ili
t
y
p
r
o
p
er
t
y
b
et
w
e
en
t
w
o
n
o
d
es
in
t
h
e
n
et
w
o
r
k
)
,
in
s
u
c
h
a
w
a
y
t
h
at
th
e
s
ati
s
f
iab
ilit
y
o
f
t
h
e
f
o
r
m
u
l
as i
m
p
lie
s
th
e
tr
u
t
h
o
f
th
e
s
p
ec
if
ied
p
r
o
p
er
ties
.
Fig
u
r
e
2
illu
s
tr
ates
th
e
s
et
o
f
to
p
o
lo
g
ies
ad
o
p
ted
f
o
r
o
u
r
test
s
.
Fo
r
ex
a
m
p
le,
to
p
o
lo
g
y
(
1
)
in
v
o
l
v
es
t
w
o
f
ir
e
w
alls
a
n
d
th
r
ee
en
d
h
o
s
ts
.
Fire
w
all
s
ar
e
co
n
f
i
g
u
r
ed
ac
co
r
d
in
g
to
th
e
f
o
llo
w
i
n
g
r
u
le
s
:
-
Fire
w
a
ll 1
d
en
ies tr
af
f
ic
b
et
w
e
en
h
o
s
t
A
a
n
d
h
o
s
t
C
.
-
Fire
w
a
ll 2
d
en
ies tr
af
f
ic
b
et
w
e
en
h
o
s
t B
an
d
h
o
s
t C.
Fig
u
r
e
2
.
Set o
f
n
et
w
o
r
k
to
p
o
l
o
g
ies cr
ea
ted
f
o
r
th
e
v
er
i
f
icat
i
o
n
p
r
o
ce
s
s
T
h
e
test
in
cl
u
d
es
t
w
o
r
ea
c
h
ab
ilit
y
p
r
o
p
er
ties
to
b
e
ch
ec
k
ed
.
I
n
p
ar
ticu
lar
,
w
e
co
n
s
id
er
t
wo
p
ac
k
ets,
o
n
e
f
lo
w
in
g
f
r
o
m
n
o
d
e
A
to
n
o
d
e
C
,
an
d
an
o
th
er
f
lo
w
i
n
g
f
r
o
m
n
o
d
e
A
to
n
o
d
e
B
.
T
ak
in
g
i
n
to
ac
co
u
n
t
t
h
e
ab
o
v
e
f
ir
e
w
all
p
o
licies,
w
e
e
x
p
ec
t
th
e
r
ea
ch
ab
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y
p
r
o
p
er
ty
is
n
o
t
s
a
tis
f
ied
in
ca
s
e
o
f
A
-
to
-
C
,
i
n
d
icati
n
g
t
h
at
n
o
s
u
c
h
p
ac
k
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t
ca
n
e
x
i
s
t,
w
h
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w
e
e
x
p
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t
it
i
s
s
ati
s
f
ied
in
t
h
e
ca
s
e
o
f
A
-
to
-
B
.
T
h
e
o
th
er
t
est
ca
s
es
ar
e
s
et
u
p
as f
o
llo
w
s
(
t
h
e
n
u
m
b
er
i
n
b
r
ac
k
ets r
e
f
er
s
to
th
e
co
r
r
esp
o
n
d
in
g
to
p
o
lo
g
y
in
Fi
g
u
r
e
2
)
:
1.
C
o
n
f
i
g
u
r
atio
n
s
:
f
ir
e
w
all
d
e
n
ie
s
tr
af
f
ic
b
et
w
ee
n
h
o
s
t
C
a
n
d
h
o
s
t
B
;
t
h
e
ca
ch
e
i
s
s
et
to
s
er
v
e
an
y
r
eq
u
e
s
t
(
an
y
U
R
L
o
f
t
h
e
r
eso
u
r
ce
r
eq
u
ested
i
s
p
r
esen
t
i
n
t
h
e
ca
c
h
e)
;
h
o
s
t
A
s
en
d
s
an
HT
T
P
R
E
Q
UE
ST
to
w
ar
d
s
B
;
h
o
s
t
A
an
d
C
ar
e
s
et
as
in
t
er
n
al
n
o
d
es
o
f
N
A
T
an
d
ca
ch
e.
P
r
o
p
er
ty
:
r
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ch
ab
ilit
y
b
et
wee
n
h
o
s
t
A
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d
h
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t B
.
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es
u
lt:
n
o
t r
ea
ch
ab
le.
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ea
s
o
n
: c
ac
h
e
n
e
v
er
f
o
r
w
ar
d
s
p
ac
k
ets to
w
ar
d
s
h
o
s
t B
.
2.
C
o
n
f
i
g
u
r
atio
n
s
:
a
n
ti
s
p
a
m
b
lo
ck
s
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tr
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(
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ai
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l
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li
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o
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n
et
w
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k
f
u
n
ct
io
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.
P
r
o
p
er
t
y
:
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il
it
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b
et
w
ee
n
m
ail
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v
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an
d
(
m
ai
l)
clien
t.
A
ct
io
n
:
s
e
n
d
a
p
ac
k
et
f
r
o
m
m
ail
clie
n
t
to
m
ail
s
e
r
v
er
.
R
esu
l
t:
n
o
t
r
ea
ch
ab
le.
R
ea
s
o
n
: a
n
ti
s
p
a
m
d
r
o
p
s
p
ac
k
ets s
en
t to
w
ar
d
s
m
ail
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er
v
er
.
3.
C
o
n
f
i
g
u
r
atio
n
s
:
I
DS
d
r
o
p
s
a
p
ac
k
et
co
n
tain
i
n
g
a
s
p
ec
if
ic
s
tr
in
g
i
n
th
e
b
o
d
y
o
f
t
h
e
p
ac
k
et;
h
o
s
t
s
en
d
s
a
p
ac
k
et
co
n
tai
n
i
n
g
t
h
e
s
p
ec
i
f
i
c
s
tr
in
g
in
th
e
b
o
d
y
.
P
r
o
p
er
ty
:
r
ea
ch
ab
il
it
y
b
e
t
w
ee
n
h
o
s
t
an
d
w
eb
s
er
v
er
.
R
es
u
lt:
n
o
t r
ea
ch
ab
le.
R
ea
s
o
n
:
I
DS d
r
o
p
s
p
ac
k
ets co
n
tain
i
n
g
th
e
s
p
ec
if
ic
s
tr
i
n
g
i
n
t
h
e
b
o
d
y
o
f
th
e
p
ac
k
et.
4.
C
o
n
f
i
g
u
r
atio
n
s
:
r
eq
u
e
s
ts
ca
n
n
o
t
b
e
s
er
v
ed
b
y
t
h
e
ca
ch
e
(
t
h
e
UR
L
o
f
t
h
e
r
eso
u
r
ce
r
eq
u
este
d
is
n
o
t
p
r
esen
t
in
t
h
e
ca
ch
e)
.
P
r
o
p
er
ty
:
r
ea
c
h
ab
ilit
y
b
et
w
ee
n
h
o
s
t
A
an
d
h
o
s
t
B
.
R
es
u
lt
:
r
ea
ch
ab
le.
R
ea
s
o
n
:
ca
ch
e
f
o
r
w
ar
d
s
p
ac
k
e
ts
,
s
i
n
ce
r
eq
u
es
ted
p
ac
k
ets ar
e
n
o
t p
r
esen
t i
n
ca
ch
e
tab
le.
Evaluation Warning : The document was created with Spire.PDF for Python.
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5.
C
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f
i
g
u
r
atio
n
s
:
f
ir
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w
all
d
en
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es
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af
f
ic
b
et
w
ee
n
h
o
s
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a
n
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w
eb
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;
ca
c
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is
s
et
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an
y
r
eq
u
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s
t.
P
r
o
p
er
ty
:
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ea
ch
ab
ilit
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b
et
w
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n
h
o
s
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er
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l
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f
ir
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w
all
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lo
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s
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h
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n
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if
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p
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m
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d
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ated
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r
f
r
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w
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k
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h
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tr
in
g
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A
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atica
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u
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m
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ased
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atica
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2
th
US
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m
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n
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.
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]
S
.
Ow
re
,
e
t
a
l
.
,
“
P
v
s:
A
p
ro
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y
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ri
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ica
ti
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n
sy
ste
m
,
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.
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9
2
.
[4
]
H.
M
a
i,
e
t
a
l
.
,
“
De
b
u
g
g
in
g
th
e
d
a
ta
p
lan
e
w
it
h
a
n
tea
ter,”
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c
e
e
d
in
g
s
o
f
t
h
e
ACM
S
IGCO
M
M
2
0
1
1
C
o
n
fer
e
n
c
e
,
se
r.
S
IGCO
M
M
’1
1
.
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rk
,
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Y
,
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A:
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,
p
p
.
2
9
0
-
3
0
1
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2
0
1
1
.
[5
]
R.
S
to
e
n
e
sc
u
,
e
t
a
l
.
,
“
S
c
a
lab
le
S
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li
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E
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ti
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f
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r
M
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rn
Ne
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o
rk
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e
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d
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th
e
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M
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0
1
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n
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e
,
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p
.
3
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4
-
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7
,
2
0
1
6
.
[6
]
S
.
S
p
i
n
o
s
o
,
e
t
a
l
.
,
“
F
o
rm
a
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V
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ica
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n
o
f
V
irt
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ra
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ro
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o
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ly
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p
.
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[7
]
L
.
De
M
o
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ra
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n
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Bjø
rn
e
r,
“
Z
3
:
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n
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t
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M
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[8
]
J.
C.
Co
rb
e
t
t,
e
t
a
l
.
,
“
Ba
n
d
e
ra
:
˘
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trac
ti
n
g
F
in
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e
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sta
te
M
o
d
e
ls
f
r
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m
Ja
v
a
S
o
u
rc
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Co
d
e
,
”
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e
e
d
i
n
g
s
o
f
th
e
2
2
N
d
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ter
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l
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fer
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g
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r.
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A:
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.
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.
[9
]
K.
Ha
v
e
lu
n
d
a
n
d
T
.
P
re
ss
b
u
rg
e
r,
“
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.
K.
F
a
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z
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l
.
,
“
BUZZ:
T
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stin
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tex
t
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e
n
t
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li
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n
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tate
f
u
l
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w
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rk
s,”
1
3
th
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E
NIX
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y
mp
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siu
m
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n
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[1
1
]
W
.
W
u
,
e
t
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l
.
,
“
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u
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ti
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n
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d
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g
s
o
f
t
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e
1
5
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h
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o
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r.
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6
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rk
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S
A
:
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p
p
.
2
9
-
35
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0
1
6
.
[1
2
]
J.
Kh
a
li
d
,
e
t
a
l
.
,
“
P
a
v
in
g
th
e
w
a
y
f
o
r
n
fv
:
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i
m
p
li
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m
id
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leb
o
x
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if
ica
ti
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u
sin
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sta
tea
ly
z
r,
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e
e
d
in
g
s
o
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1
3
t
h
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e
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ix
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e
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ms
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n
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n
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p
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,
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r.
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DI’1
6
.
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k
e
ley
,
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A:
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ENIX
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n
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p
.
2
3
9
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2
5
3
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0
1
6
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[1
3
]
M
.
W
e
ise
r,
“
P
ro
g
ra
m
slicin
g
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”
Pro
c
e
e
d
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g
s
o
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e
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th
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ti
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l
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re
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e
o
n
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o
ft
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re
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g
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e
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g
,
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r.
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E
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1
.
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isc
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A:
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p
.
4
3
9
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4
4
9
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1
9
8
1
.
[1
4
]
H.
A
g
r
a
w
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l
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n
d
J.
R.
Ho
rg
a
n
,
“
Dy
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c
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ra
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slicin
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n
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p
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2
4
6
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5
6
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0
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5
]
“
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A
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ti
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A
v
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[1
6
]
E.
F
a
u
z
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e
t
a
l
.
,
“
Re
v
e
rse
e
n
g
in
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rc
e
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o
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e
to
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q
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e
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ra
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u
sin
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a
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t
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tree
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0
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ter
n
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t
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n
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re
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p
.
1
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6
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2
0
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6
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7
]
N.
M
c
Ke
o
w
n
,
e
t
a
l
.
,
“
Op
e
n
F
lo
w
:
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a
b
li
n
g
In
n
o
v
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ti
o
n
i
n
Ca
m
p
u
s
Ne
tw
o
rk
s,”
S
IGCO
M
M
Co
mp
u
t.
Co
mm
u
n
.
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8
]
B.
T
sc
h
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e
n
,
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t
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l
.
,
“
S
f
c
-
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h
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n
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ti
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in
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p
p
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9
]
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.
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n
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,
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l
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“
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ro
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le
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l.
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s/
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4
0
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0
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B.
En
d
e
rto
n
,
“
A
m
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th
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a
ti
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to
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:
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ico
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ro
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re
a
n
d
c
o
m
m
u
n
ica
ti
o
n
p
r
o
to
c
o
l
e
n
g
in
e
e
rin
g
,
d
istr
ib
u
ted
sy
ste
m
s,
a
n
d
c
o
m
p
u
ter
se
c
u
rit
y
.
He
h
a
s
a
u
th
o
re
d
a
n
d
c
o
-
a
u
th
o
re
d
m
o
re
th
a
n
1
0
0
sc
ien
ti
f
ic p
a
p
e
rs.
He
is a S
e
n
i
o
r
M
e
m
b
e
r
o
f
th
e
A
CM
.
M
a
tte
o
V
irg
il
io
re
c
e
iv
e
d
th
e
M
.
S
.
d
e
g
re
e
in
Co
m
p
u
ter
En
g
in
e
e
rin
g
f
ro
m
P
o
li
tec
n
ic
o
d
i
T
o
rin
o
,
Italy
,
in
2
0
1
2
.
He
g
o
t
h
is
P
h
.
D.
i
n
Co
n
tr
o
l
a
n
d
C
o
m
p
u
ter
E
n
g
in
e
e
rin
g
a
t
P
o
li
tec
n
ic
o
d
i
T
o
rin
o
.
His
re
se
a
rc
h
in
tere
sts
in
c
lu
d
e
i
n
n
o
v
a
ti
v
e
n
e
tw
o
rk
p
ro
to
c
o
ls
a
n
d
a
rc
h
it
e
c
tu
re
s,
C
o
n
te
n
t
Ce
n
tr
ic
Ne
tw
o
rk
in
g
a
n
d
f
o
r
m
a
l
v
e
rif
ic
a
ti
o
n
tec
h
n
iq
u
e
s a
p
p
li
e
d
i
n
t
h
e
c
o
n
tex
t
S
DN
/NF
V
.
J
a
lo
ll
id
d
i
n
Yu
s
u
p
o
v
re
c
e
i
v
e
d
th
e
M
.
S
.
d
e
g
re
e
in
C
o
m
p
u
ter
En
g
i
n
e
e
rin
g
f
ro
m
P
o
li
tec
n
ico
d
i
T
o
rin
o
,
Italy
,
in
2
0
1
6
.
Cu
rre
n
tl
y
,
He
is
a
P
h
.
D.
st
u
d
e
n
t
i
n
C
o
n
tr
o
l
a
n
d
Co
m
p
u
ter
En
g
in
e
e
rin
g
a
t
P
o
li
tec
n
ic
o
d
i
T
o
rin
o
.
His p
rim
a
r
y
re
se
a
r
c
h
in
tere
sts in
c
lu
d
e
f
o
rm
a
l
v
e
ri
f
ica
ti
o
n
o
f
se
c
u
rit
y
p
o
li
c
ies
in
a
u
to
m
a
ted
n
e
tw
o
rk
o
rc
h
e
stra
ti
o
n
.
His
o
th
e
r
re
se
a
r
c
h
in
tere
sts
in
c
lu
d
e
m
o
d
e
li
n
g
,
c
y
b
e
r
p
h
y
si
c
a
l
s
y
ste
m
s,
a
n
d
c
lo
u
d
c
o
m
p
u
ti
n
g
sy
ste
m
s.
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