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Vo
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11
,
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.
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A
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g
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s
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2021
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p
p
.
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SS
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8708
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K
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k
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Net
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k
co
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f
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o
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So
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t
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n
ed
n
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c
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rticle
u
n
d
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CC B
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C
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A
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Dep
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aq
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2
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aq
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r
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ag
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co
m
1.
I
NT
RO
D
UCT
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ec
en
t
l
y
,
t
h
e
n
u
m
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er
s
h
as
r
is
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e
x
p
o
n
en
tia
ll
y
,
t
h
i
s
u
r
g
ed
th
e
n
et
w
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r
k
o
p
er
ato
r
s
a
n
d
v
e
n
d
o
r
s
to
s
ee
k
n
e
w
n
et
w
o
r
k
d
es
ig
n
s
a
n
d
ad
v
an
ce
d
an
n
ao
v
a
tio
n
s
[
1
]
.
T
o
d
ay
,
co
m
p
u
ter
n
et
w
o
r
k
s
ar
e
u
s
ed
ex
te
n
s
iv
el
y
to
en
ab
le
co
m
m
u
n
icatio
n
t
h
r
o
u
g
h
o
u
t
t
h
e
g
lo
b
e.
W
i
-
Fi
an
d
ce
llu
lar
n
et
w
o
r
k
s
s
h
all
b
e
v
er
y
ad
ap
tab
le
w
it
h
i
n
th
eir
n
et
w
o
r
k
in
f
r
astr
u
ct
u
r
e.
A
r
e
s
o
lu
tio
n
to
t
h
i
s
is
m
o
v
i
n
g
t
h
e
c
u
r
r
en
t
n
et
w
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r
k
s
to
w
ar
d
s
m
o
r
e
f
lex
ib
le
an
d
ea
s
ier
to
m
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ip
u
late
ar
ch
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tectu
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ca
lled
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o
f
t
w
ar
e
d
ef
in
ed
n
e
t
w
o
r
k
(
SD
N)
[
2
]
.
SDN
i
s
an
e
m
er
g
i
n
g
n
e
t
w
o
r
k
d
esig
n
t
h
at
i
s
d
y
n
a
m
ic,
m
an
a
g
ea
b
le
an
d
co
s
t
-
ef
f
ec
ti
v
e.
SDN
ca
n
b
o
o
s
t
th
e
n
e
t
w
o
r
k
u
p
f
o
r
th
e
b
an
d
wid
th
-
h
u
n
g
r
y
ap
p
licatio
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s
,
w
h
i
ch
is
t
h
e
n
atu
r
e
o
f
to
d
a
y
'
s
r
eq
u
ir
e
m
e
n
t
s
[
3
]
.
SDN
ar
ch
itect
u
r
e
d
ec
o
u
p
les
t
h
e
n
et
w
o
r
k
’
s
co
n
tr
o
l
a
n
d
f
o
r
war
d
in
g
f
u
n
ct
io
n
s
an
d
p
er
m
i
ts
t
h
e
u
n
d
er
l
y
in
g
in
f
r
astru
ct
u
r
e
to
b
e
ab
s
tr
ac
ted
f
o
r
n
et
w
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k
s
er
v
ices
v
ia
ab
s
tr
ac
tin
g
t
h
e
n
et
w
o
r
k
eq
u
ip
m
e
n
t
an
d
th
e
ir
o
p
er
atin
g
s
y
s
te
m
.
I
t
e
n
ab
les
th
e
co
n
tr
o
l
p
lan
e
to
b
ec
o
m
e
d
ir
ec
tl
y
p
r
o
g
r
a
m
m
ab
le
an
d
m
o
v
ed
i
n
t
o
a
ce
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tr
al
lo
ca
tio
n
w
it
h
i
n
t
h
e
n
et
w
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r
k
,
ca
lled
“
co
n
tr
o
ller
”
[
4
].
T
h
e
tw
o
m
ain
p
ar
ities
i
n
th
i
s
ar
ch
itect
u
r
e
ar
e
th
e
co
n
tr
o
ller
s
an
d
s
w
itc
h
es,
w
h
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th
e
f
o
r
m
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m
a
k
es
d
ec
is
io
n
s
w
h
er
e
in
f
o
r
m
atio
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g
o
es,
an
d
th
e
lat
ter
is
r
esp
o
n
s
ib
le
f
o
r
m
o
v
i
n
g
in
f
o
r
m
a
tio
n
h
o
p
-
by
-
h
o
p
[
5
]
.
I
n
b
et
w
ee
n
t
h
e
co
n
tr
o
ller
an
d
t
h
e
s
w
itc
h
,
co
m
e
s
th
e
c
h
a
n
n
e
l,
also
ca
lled
o
p
en
f
lo
w
p
r
o
to
co
l
th
at
i
s
r
esp
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n
s
ib
le
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
11
,
No
.
4
,
A
u
g
u
s
t
2021
:
3
1
4
5
-
3153
3146
f
o
r
th
e
n
ec
e
s
s
ar
y
co
m
m
u
n
ica
ti
o
n
s
[
6
]
.
T
h
e
co
n
tr
o
ller
u
s
es
th
i
s
c
h
an
n
el
to
in
s
tall
o
p
en
f
lo
w
tab
le
s
i
n
to
t
h
e
s
w
itc
h
es,
t
h
i
s
tab
le
co
n
ta
in
s
f
lo
w
e
n
tr
ies,
s
u
ch
as
I
P
an
d
MA
C
ad
d
r
ess
es,
an
d
h
o
ld
s
t
h
e
n
ec
es
s
ar
y
r
o
u
tin
g
in
f
o
r
m
atio
n
t
h
at
ar
e
r
eq
u
ir
ed
to
d
ir
ec
t th
e
p
ac
k
ets to
th
eir
d
esti
n
a
tio
ns
[
7
]
.
C
lear
l
y
,
t
h
e
p
lace
m
e
n
t
o
f
th
e
s
e
co
n
tr
o
ller
s
i
s
v
er
y
v
ital
f
o
r
th
e
n
et
w
o
r
k
to
r
ed
u
ce
t
h
e
l
aten
c
y
o
f
t
h
e
n
et
w
o
r
k
t
h
at
i
s
t
h
e
p
r
er
eq
u
is
it
e
o
f
5
G
an
d
b
e
y
o
n
d
s
y
s
te
m
s
.
T
h
e
o
p
tim
al
lo
ca
tio
n
o
f
f
er
s
r
e
d
u
ce
d
laten
c
y
to
all
th
e
s
w
itc
h
es
w
it
h
i
n
t
h
e
n
et
w
o
r
k
an
d
th
er
e
f
o
r
e,
r
ed
u
ce
d
late
n
c
y
to
t
h
e
n
et
w
o
r
k
s
u
b
s
cr
ib
er
s
[
8
]
.
A
cc
o
r
d
in
g
l
y
,
s
u
c
h
o
p
ti
m
izatio
n
d
ec
r
ea
s
es
th
e
tr
an
s
m
i
tted
p
o
w
er
r
eq
u
ir
ed
to
s
en
d
th
e
p
ac
k
ets
to
th
eir
d
esti
n
atio
n
s
.
On
ce
t
h
e
tr
an
s
m
itted
p
o
w
er
is
r
ed
u
ce
d
,
th
e
p
o
w
er
co
n
s
u
m
p
tio
n
o
f
t
h
e
n
et
w
o
r
k
s
is
r
ed
u
ce
d
to
o
[
9
]
.
A
t
t
h
e
e
n
d
,
t
h
e
n
et
w
o
r
k
e
f
f
icie
n
c
y
s
h
all
b
e
e
n
h
a
n
ce
d
.
Hen
ce
,
th
i
s
w
o
r
k
s
h
ed
s
lig
h
t
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n
tr
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ller
’
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m
e
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n
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tic
co
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s
tr
ai
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m
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m
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e
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t
w
h
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m
i
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in
g
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m
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a
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d
th
e
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p
e
s
o
f
co
n
tr
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s
to
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e
o
p
tim
is
ed
[1
0]
.
Dif
f
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n
t
co
n
s
tr
ain
t
s
an
d
n
et
w
o
r
k
m
etr
ics,
s
u
c
h
as
co
n
tr
o
ller
ca
p
ac
it
y
,
co
n
tr
o
ller
an
d
lin
k
t
y
p
es,
li
n
k
b
an
d
w
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t
h
a
n
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co
n
n
ec
t
iv
i
t
y
o
f
th
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n
et
w
o
r
k
d
ev
ices
h
av
e
b
ee
n
co
n
s
id
er
ed
.
T
o
ac
h
ie
v
e
t
h
is
,
th
e
f
o
llo
w
in
g
co
n
tr
ib
u
tio
n
s
h
a
v
e
b
ee
n
m
ad
e:
Giv
e
n
th
e
m
a
n
y
ch
a
n
g
es
r
elat
ed
to
th
e
co
n
tr
o
ller
,
w
e
p
r
ese
n
ted
a
m
o
d
el
t
h
at
d
ec
id
es
to
s
u
p
p
l
y
t
h
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id
ea
l
n
u
m
b
er
,
ar
ea
an
d
t
y
p
e
o
f
co
n
t
r
o
ller
at
th
e
s
a
m
e
ti
m
e.
T
h
e
p
u
r
p
o
s
e
o
f
t
h
e
m
o
d
e
l
i
s
t
o
r
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d
u
c
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t
w
o
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k
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o
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t
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b
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a
k
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c
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o
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n
t
r
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q
u
i
r
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m
e
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t
s
s
u
c
h
a
s
t
h
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c
o
n
t
r
o
l
l
e
r
'
s
r
a
n
g
e
,
c
o
n
t
a
c
t
a
r
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a
a
n
d
p
o
w
e
r
m
a
n
a
g
e
m
e
n
t
d
is
ta
n
ce
.
E
v
alu
a
tio
n
o
f
t
h
e
o
f
f
er
o
f
t
h
e
co
r
r
esp
o
n
d
in
g
m
o
d
el
an
d
cr
ea
te
t
y
p
o
lo
g
ies i
n
d
if
f
er
en
t sizes
.
Dev
elo
p
t
y
p
o
lo
g
ies ar
ea
s
t
h
at
d
eter
m
in
e
h
o
w
th
e
n
u
m
b
er
o
f
p
o
ten
tial a
r
ea
s
m
a
y
af
f
ec
t
u
til
i
ties
.
T
o
ev
alu
ate
o
r
g
a
n
i
z
a
t
i
o
n
a
l
p
e
r
f
o
r
m
a
n
c
e
b
y
e
x
p
a
n
d
i
n
g
t
h
e
s
i
z
e
o
f
t
h
e
n
e
tw
o
r
k
i
n
o
r
d
e
r
t
o
e
s
t
i
m
a
t
e
t
h
e
co
s
t.
Ass
es
s
m
en
t
o
f
th
e
co
n
tr
o
lli
n
g
b
o
d
y
a
n
d
li
m
itatio
n
o
f
t
h
e
n
u
m
b
er
o
f
co
n
tr
o
ller
s
a
s
i
n
d
ica
ted
b
y
th
e
d
y
n
a
m
ic
u
n
d
er
s
ta
n
d
i
n
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o
f
tr
a
f
f
ic
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d
th
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p
r
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v
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m
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n
t
o
f
th
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u
s
e
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f
r
eso
u
r
ce
s
b
y
t
h
e
co
n
t
r
o
ller
'
s
n
et
w
o
r
k
to
ch
an
g
e
lin
k
s
.
W
e
h
av
e
p
r
o
v
id
ed
f
o
r
a
d
ir
ec
t
ab
ilit
y
to
m
o
n
ito
r
th
e
p
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f
o
r
m
an
ce
o
f
t
h
e
co
n
tr
o
ller
s
b
ased
o
n
co
n
tin
u
o
u
s
f
ee
d
b
ac
k
f
r
o
m
t
h
e
cu
r
r
en
t
m
o
n
ito
r
i
n
g
b
o
d
y
i
n
a
cc
o
r
d
an
ce
w
it
h
m
an
d
ato
r
y
r
e
g
u
la
tio
n
s
.
W
e
h
av
e
als
o
p
r
o
p
o
s
ed
a
r
ec
lass
if
ica
ti
o
n
alg
o
r
it
h
m
to
s
p
ee
d
u
p
t
h
e
ad
j
u
s
t
m
e
n
t
o
f
t
h
e
b
u
r
d
en
b
etw
ee
n
co
n
tr
o
ller
s
.
I
n
ad
d
itio
n
,
a
f
aili
n
g
ele
m
e
n
t a
i
m
s
to
s
o
lv
e
t
h
e
p
r
o
b
l
em
o
f
co
n
tr
o
ller
d
is
ap
p
o
in
t
m
en
t
[
1
1
]
.
2.
RE
L
AT
E
D
WO
RK
S
I
n
o
r
d
er
to
d
ef
in
e
t
h
e
co
n
tr
o
ll
er
p
r
o
b
lem
,
a
m
at
h
e
m
a
tical
m
o
d
el
is
r
eq
u
ir
ed
to
r
e
p
r
esen
t
th
e
b
eh
av
io
r
o
f
SDN
tr
af
f
ic
[
1
2
]
.
W
e
h
av
e
u
s
ed
a
s
o
lv
er
ca
lled
C
P
L
E
X
to
r
etu
r
n
s
t
h
e
o
p
ti
m
al
s
o
l
u
tio
n
o
r
t
h
e
b
e
s
t
s
o
l
u
t
i
o
n
f
o
u
n
d
w
h
e
n
t
h
e
t
im
e
l
i
m
i
t
i
s
r
e
a
c
h
e
d
.
S
i
n
c
e
t
h
e
f
i
r
s
t
i
n
t
r
o
d
u
c
t
i
o
n
o
f
t
h
e
S
D
N
c
o
n
t
r
o
l
l
e
r
i
s
s
u
e
b
y
H
e
l
l
e
r
et
a
l.
[
7
]
,
m
an
y
r
esear
c
h
er
s
h
a
v
e
p
r
o
p
o
s
ed
d
if
f
er
e
n
t
alg
o
r
it
h
m
s
f
o
r
d
ea
lin
g
w
i
th
o
n
e
o
f
th
e
m
o
s
t
d
if
f
ic
u
lt
p
r
o
b
le
m
s
f
ac
i
n
g
a
n
en
g
i
n
ee
r
w
ith
r
esp
ec
t to
d
ep
lo
y
in
g
an
SDN
n
et
w
o
r
k
: th
e
p
lace
m
e
n
t o
f
co
n
tr
o
ller
s
in
th
e
n
et
w
o
r
k
.
A
f
o
r
m
id
ab
le
ch
al
le
n
g
e
as
s
o
ci
ated
w
it
h
s
o
lv
i
n
g
SDN
co
n
tr
o
l
ler
p
lace
m
e
n
t
p
r
o
b
lem
s
is
th
at
all
o
f
th
e
alg
o
r
ith
m
s
p
r
o
p
o
s
ed
in
v
o
l
v
e
a
tr
ad
eo
f
f
a
m
o
n
g
s
ca
lab
il
it
y
,
r
esil
ien
ce
,
an
d
m
o
d
el
e
x
p
an
s
i
o
n
[
1
3
,
14]
.
W
ith
r
esp
ec
t
to
in
v
esti
g
atio
n
s
o
f
t
h
e
SDN
co
n
tr
o
ller
p
r
o
b
lem
,
t
h
e
tech
n
ic
al
p
ap
er
p
u
b
lis
h
ed
b
y
Heller
et
a
l.
[1
5
]
is
o
n
e
o
f
th
e
m
o
s
t
cited
.
T
h
e
au
th
o
r
s
p
r
o
p
o
s
ed
a
h
eu
r
is
tic
ap
p
r
o
ac
h
to
f
in
d
in
g
th
e
id
ea
l
r
o
le
f
o
r
co
n
tr
o
ller
s
in
lar
g
e
SDN
o
r
g
a
n
izatio
n
s
.
I
n
th
is
s
tu
d
y
,
th
e
m
ai
n
p
r
ed
ictio
n
w
a
s
th
e
n
o
r
m
al
i
n
ac
ti
v
it
y
s
ce
n
ar
io
,
w
h
ic
h
is
co
n
s
id
er
ed
ess
e
n
tial
i
n
d
eter
m
in
i
n
g
t
h
e
i
n
er
tia
e
s
ti
m
ates
r
eq
u
ir
ed
f
o
r
lar
g
e
-
s
ca
le
SDN
u
s
e
[
1
6
]
.
T
h
e
ap
p
r
o
ac
h
is
d
ep
en
d
en
t p
r
i
m
ar
il
y
o
n
p
r
o
p
ag
atio
n
d
ela
y
,
w
it
h
t
h
e
lo
ca
ti
o
n
o
f
a
co
n
tr
o
ller
b
ein
g
b
ased
o
n
th
e
s
h
o
r
test
p
at
h
b
et
w
ee
n
s
w
itc
h
es
a
n
d
co
n
tr
o
ller
s
th
at
h
a
v
e
b
ee
n
ass
i
g
n
ed
in
th
e
n
et
w
o
r
k
to
p
o
lo
g
y
[
1
7
]
.
T
h
is
s
tu
d
y
o
f
f
er
ed
th
e
m
o
s
t
ac
c
u
r
ate
s
o
lu
tio
n
f
o
r
ad
d
r
ess
in
g
th
e
p
r
o
b
le
m
.
An
in
ter
es
tin
g
co
n
cl
u
s
io
n
w
as
th
at
in
cr
ea
s
in
g
th
e
n
u
m
b
er
o
f
co
n
tr
o
ller
s
d
o
es
n
o
t
n
ec
es
s
ar
il
y
d
ec
r
ea
s
e
t
h
e
av
er
ag
e
late
n
c
y
b
et
w
ee
n
s
w
i
tch
es
a
n
d
ass
i
g
n
ed
co
n
tr
o
ller
s
[
1
8
]
.
3.
RE
S
E
ARCH
M
E
T
H
O
D
W
e
r
ec
eiv
ed
an
u
n
d
ir
ec
ted
o
r
g
an
izatio
n
to
p
o
lo
g
y
(
,
)
,
w
h
er
e
in
d
icate
s
t
h
e
ar
r
an
g
e
m
e
n
t
o
f
s
w
itc
h
es
a
n
d
i
s
t
h
e
ar
r
an
g
e
m
en
t
o
f
ed
g
es
in
th
e
m
id
d
l
e.
L
et
s
p
ea
k
s
to
t
h
e
ar
r
an
g
e
m
e
n
t
o
f
d
y
n
a
m
ic
co
n
tr
o
ller
s
an
d
is
th
e
q
u
a
n
tit
y
o
f
co
n
tr
o
ller
s
,
w
h
ic
h
is
1
as
a
m
a
tter
o
f
co
u
r
s
e.
=
[
]
|
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m
ea
n
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th
e
task
r
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n
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a
m
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Fo
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w
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3
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e.
Miss
i
n
g
p
ac
k
et
i
n
clu
d
e
b
o
th
th
e
p
ac
k
et
p
r
o
v
id
ed
b
y
t
h
e
c
o
n
tr
o
ller
an
d
th
e
ass
o
ciate
d
s
w
itc
h
e
s
.
A
p
ac
k
et
is
s
u
ed
b
y
th
e
d
r
iv
er
en
s
u
r
es
th
at
th
e
d
r
iv
er
w
ill
b
e
o
v
er
lo
ad
ed
.
A
s
s
u
m
i
n
g
w
e
d
o
n
o
t
t
h
in
k
ab
o
u
t
g
o
o
d
an
d
u
p
-
d
o
w
n
s
w
i
tch
ti
m
es,
th
e
p
ac
k
et
th
at
r
e
m
o
v
es
t
h
e
as
s
o
ciate
d
s
w
itc
h
e
s
al
s
o
s
h
o
w
s
th
a
t
t
h
e
co
n
tr
o
ller
i
g
n
o
r
es
th
e
f
lo
w
s
etti
n
g
p
r
o
b
lem
s
.
As
s
h
o
w
n
in
(
6
)
d
eter
m
in
e
s
w
h
e
th
er
ea
ch
s
w
itc
h
is
a
s
s
i
g
n
ed
to
o
n
e
co
n
tr
o
ller
an
d
o
n
e
co
n
tr
o
ller
[
1
9
,
20]
.
3
.
2
.
E
v
a
lua
t
io
n f
un
ct
io
n
I
n
o
r
d
er
to
ev
alu
ate
th
e
u
t
il
it
y
o
f
a
co
n
tr
o
ller
,
an
ev
a
lu
atio
n
f
u
n
ctio
n
is
d
e
f
in
ed
a
f
u
n
ctio
n
o
f
t
h
e
5
m
etr
ics
f
o
r
ea
ch
co
n
tr
o
ller
:
=
(
,
,
,
,
)
(
7
)
E
ac
h
o
f
t
h
e
5
m
etr
ics
r
ef
lect
s
t
h
e
co
n
tr
o
ller
p
er
f
o
r
m
an
ce
.
W
e
d
esig
n
t
h
e
e
v
al
u
atio
n
f
u
n
ct
io
n
a
s
f
o
llo
w
s
t
h
o
u
g
h
t
h
er
e
is
m
o
r
e
th
an
o
n
e
p
o
s
s
ib
le
ex
p
r
ess
io
n
.
=
+
+
+
+
(
8
)
I
n
th
is
f
o
r
m
u
la,
,
a
n
d
ω
ar
e
co
ef
f
icie
n
t
s
t
h
at
ca
n
b
e
r
ed
o
n
e
to
alter
th
e
g
e
n
er
al
ce
n
tr
alit
y
o
f
th
e
5
m
ea
s
u
r
e
m
e
n
t
s
.
is
s
ta
n
d
ar
d
ized
to
[
0
,
1
]
ex
p
ec
tin
g
to
r
ea
r
r
an
g
e
th
e
co
u
n
t.
T
h
e
o
r
d
in
ar
y
r
a
n
g
e
o
f
i
s
in
d
icate
d
as
[
]
,
w
h
er
e
>0
an
d
<1
.
W
h
en
>
,
i
t
i
m
p
lies
c
o
n
tr
o
ller
is
o
v
er
-
b
u
r
d
en
an
d
s
u
b
o
r
d
in
ate
s
w
itc
h
es
o
u
g
h
t
to
b
e
r
ea
s
s
i
g
n
ed
to
d
if
f
er
e
n
t
co
n
tr
o
ller
s
.
O
n
t
h
e
o
f
f
c
h
an
ce
th
at
n
o
d
y
n
a
m
ic
co
n
tr
o
ller
s
h
a
v
e
en
o
u
g
h
li
m
it
(
r
eg
ar
d
in
g
p
ar
ce
l
s
h
a
n
d
lin
g
a
m
o
u
n
t)
,
an
o
t
h
er
co
n
tr
o
ller
w
ill
b
e
en
ac
ted
to
ass
u
m
e
co
n
tr
o
l o
v
e
r
th
e
u
n
a
s
s
i
g
n
ed
s
w
itc
h
es.
W
h
en
<
,
it i
m
p
lies
th
e
r
elate
d
s
w
itch
e
s
o
f
co
n
tr
o
ller
ca
n
b
e
co
n
v
er
t
ed
to
th
o
s
e
o
f
o
th
er
co
n
tr
o
ller
to
c
h
o
p
d
o
w
n
as
s
ets.
T
h
in
k
i
n
g
ab
o
u
t
t
h
e
r
eq
u
ir
e
m
en
ts
,
w
h
e
n
t
h
e
e
s
ti
m
atio
n
o
f
a
m
ea
s
u
r
e
m
e
n
t
g
o
es
p
ast
t
h
e
o
r
d
in
ar
y
ar
ea
,
t
h
e
esti
m
atio
n
o
f
th
e
ass
es
s
m
en
t
ca
p
ac
it
y
s
h
o
u
ld
s
e
e
s
tr
an
g
e
co
n
s
eq
u
e
n
tl
y
.
Su
b
s
e
q
u
en
tl
y
,
t
h
e
a
s
s
e
s
s
m
e
n
t
ca
p
ac
it
y
ca
n
b
e
c
h
a
n
g
ed
as
(
8
)
[
2
1
-
23]
.
=
∗
|
|
(
>
)
|
|
(
>
)
|
|
(
>
)
|
|
(
>
)
|
|
(
>
)
(
8
)
w
h
er
e
∗
=
+
+
+
+ω
Σ
an
d
|
|
is
t
h
e
lo
g
ical
o
p
er
ato
r
OR
.
I
f
an
y
m
etr
ics
v
io
late
th
e
co
n
s
tr
ain
ts
,
w
il
l b
ec
o
m
e
1
i
m
m
ed
iatel
y
a
n
d
tr
ig
g
er
th
e
ce
n
tr
alize
d
s
ch
ed
u
ler
p
r
o
g
r
a
m
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
11
,
No
.
4
,
A
u
g
u
s
t
2021
:
3
1
4
5
-
3153
3148
3
.
3
.
Rea
s
s
ig
n
m
e
nt
I
n
t
h
e
attac
h
ed
s
ch
ed
u
le,
t
h
e
co
n
tacts
as
s
o
ciate
d
w
it
h
e
ac
h
d
r
iv
er
ar
e
s
o
r
ted
b
y
tr
af
f
ic
k
e
y
.
Me
an
w
h
ile,
t
h
e
co
n
tr
o
ls
ar
e
s
et
at
y
o
u
r
f
in
g
er
tip
s
[
2
4
]
.
T
h
e
lar
g
est
s
tac
k
i
n
g
s
w
i
tch
es
i
n
t
h
e
o
v
er
lo
ad
co
n
tr
o
ller
ar
e
in
itiall
y
s
w
itc
h
e
d
to
an
o
th
er
d
y
n
a
m
ic
co
n
tr
o
ller
w
it
h
th
e
h
ig
h
est
a
v
a
ilab
le
l
i
m
it
s
f
o
r
ex
a
m
p
le,
p
ac
k
et
p
r
o
ce
s
s
in
g
p
r
o
b
ab
ilit
y
an
d
ar
e
in
ten
d
ed
to
r
eg
u
late
s
teel
b
et
w
ee
n
co
n
tr
o
ller
s
o
v
er
a
p
e
r
io
d
o
f
s
h
o
r
t
ti
m
e
[
2
5
,
26]
.
3
.
3
.
1
.
Alg
o
rit
h
m
1:
Rea
s
s
ig
n
m
e
nt
a
lg
o
rit
h
m
Input: Network topology
, Switch set
, Active co
ntroller set
, Traffic set
=
] |
|,
Previous assignment
Output: New assignment
∗
1:
← List of the outstanding controllers for
2: for each
from
do
3:
← Sorted list (desce
nding capacity) of controller excluding
4:
← Sorted list (descending loading) of the switches for controller
5:
← First switch in
6: while statistics of
violate the constraints (1) to (6) do
7:
← First controller in
8: if
<
−
then
9: update
← reassign switc
h
to controller
10: recalculate
,
11: else if
is the last item in
then
12: update
← add a new controller
13: recalculate
14: reset
← first switch in
15: else if
=
∅
then
16: update
,← remove
17: break
18: else
19:
← Next switch in
20: end if
21: end while
22: end for
23:
∗
←
3
.
4
.
F
a
ilo
v
er
I
n
t
h
e
f
ailo
v
er
co
m
p
o
n
e
n
t,
t
h
e
s
elec
tio
n
p
r
o
g
r
a
m
r
eg
u
lar
l
y
ch
ec
k
s
th
e
p
u
l
s
e
o
f
ea
ch
co
n
tr
o
ller
a
s
w
ell
as
t
h
e
co
n
n
ec
ted
s
tatu
s
o
f
ea
c
h
s
w
i
tch
in
ea
c
h
ti
m
e
u
n
i
t
[
2
7
]
.
W
h
en
y
o
u
id
e
n
ti
f
y
in
a
ctiv
e
co
n
tr
o
ller
s
o
r
u
n
s
p
ec
if
ied
s
w
itc
h
es,
y
o
u
s
e
t
u
p
a
u
n
i
f
ied
s
ch
ed
u
li
n
g
p
r
o
g
r
a
m
to
r
eso
lv
e
t
h
e
i
s
s
u
e.
W
e
ad
d
r
ess
th
e
is
s
u
e
in
t
w
o
s
tag
e
s
:
i
)
c
h
ec
k
th
at
th
er
e
ar
e
co
n
tr
o
ller
s
av
ailab
le
b
et
wee
n
ac
to
r
s
an
d
p
ar
tn
er
s
f
o
r
u
n
s
p
ec
if
i
ed
c
h
an
g
es
;
ii
)
I
f
n
o
ac
ce
s
s
ib
le
co
n
tr
o
ller
i
s
f
o
u
n
d
,
s
tar
t
an
o
t
h
er
co
n
tr
o
ller
to
ch
ec
k
th
e
s
w
i
tch
e
s
.
T
h
e
co
n
n
ec
tio
n
c
y
cle
i
s
s
i
m
ilar
to
th
e
r
ed
ef
i
n
itio
n
c
y
c
le,
f
o
r
ex
a
m
p
le,
t
h
e
m
o
s
t
i
m
p
o
r
tan
t
r
eq
u
ir
e
m
e
n
t
is
t
h
e
h
ea
v
iest
s
teel
s
w
itc
h
es
an
d
u
p
p
er
li
m
it c
o
n
t
r
o
ller
s
[
2
8
]
.
I
n
o
u
r
ca
s
e,
all
co
n
tr
o
ller
s
h
a
v
e
o
n
l
y
a
n
en
v
ir
o
n
m
e
n
tal
p
er
s
p
ec
tiv
e
o
n
t
h
e
to
p
o
lo
g
y
o
f
th
e
n
et
w
o
r
k
.
Sin
ce
in
o
u
r
s
it
u
atio
n
w
e
wo
u
ld
ex
p
ec
t
th
e
co
n
tr
o
ller
s
t
o
o
n
l
y
d
ea
l
w
it
h
la
y
er
2
le
ar
n
in
g
a
n
d
s
tar
tu
p
p
r
o
b
lem
s
,
t
h
e
y
ca
n
,
o
f
co
u
r
s
e,
lear
n
th
e
M
AC
ad
d
r
ess
a
n
d
s
p
ec
if
y
th
e
ad
d
r
ess
.
T
h
u
s
,
af
ter
t
h
e
r
ed
ef
i
n
ed
c
y
cle,
co
n
tr
o
ller
s
ca
n
b
ec
o
m
e
a
w
ar
e
o
f
t
h
e
to
p
o
lo
g
ical
c
h
a
n
g
e
a
n
d
ad
ap
t
as
n
ee
d
ed
.
T
o
s
tar
t
at
lev
e
l
3
,
th
e
co
n
tr
o
ller
m
u
s
t
f
in
d
a
w
a
y
to
o
b
tain
i
n
f
o
r
m
atio
n
ab
o
u
t
t
h
e
n
e
w
to
p
o
lo
g
y
at
an
y
ti
m
e
wh
en
r
e
-
m
ap
p
in
g
t
h
e
s
w
itc
h
,
w
h
ic
h
w
ill b
e
co
n
s
id
er
ed
in
th
e
n
e
x
t
s
tep
.
4.
RE
SU
L
T
S
A
ND
D
I
SCU
SS
I
O
N
4
.
1
.
E
v
a
lua
t
io
n o
ne
-
F
a
ilo
v
er
As
m
e
n
tio
n
ed
i
n
th
e
as
s
es
s
m
e
n
t
s
y
s
te
m
,
th
e
s
tatis
tics
ap
p
licatio
n
is
ac
q
u
ir
ed
b
y
th
e
m
an
a
g
er
f
o
r
th
e
s
tatis
t
ics
ap
p
licatio
n
o
f
t
h
e
to
p
o
lo
g
y
p
ar
tn
er
Mi
n
i
n
et,
w
h
ic
h
al
w
a
y
s
ex
a
m
i
n
es
t
h
e
p
o
s
itio
n
o
f
t
h
e
as
s
o
ciatio
n
b
et
w
ee
n
th
e
s
w
itc
h
e
s
an
d
t
h
e
ac
tiv
it
y
o
f
th
e
m
a
n
ag
er
.
I
f
t
h
er
e
is
n
o
ch
a
n
ce
t
h
at
th
e
co
n
n
ec
t
io
n
s
tatu
s
w
ill
s
to
p
,
an
i
m
m
ed
iate
o
p
p
o
r
tu
n
i
t
y
f
o
r
th
e
ex
ter
n
al
s
ch
ed
u
ler
i
s
cr
e
ated
in
th
e
s
c
h
ed
u
ler
.
He
n
ce
,
t
h
e
s
c
h
ed
u
ler
s
tar
ts
i
m
m
ed
iatel
y
an
d
d
esi
g
n
s
an
o
th
er
/
c
u
r
r
en
t
co
n
tr
o
lle
r
f
o
r
u
s
er
s
w
h
o
co
m
p
ar
e
s
w
itc
h
e
s
.
Ou
r
b
asic
ev
alu
a
tio
n
r
e
s
u
lt
s
s
h
o
w
t
h
at
t
h
e
s
w
itch
e
s
ca
n
b
e
r
ec
o
n
n
ec
t
ed
to
th
e
AC
T
I
ON
co
u
n
ter
i
n
3
s
ec
o
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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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&
C
o
m
p
E
n
g
,
Vo
l.
11
,
No
.
4
,
A
u
g
u
s
t
2021
:
3
1
4
5
-
3153
3150
So
m
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3
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I
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n
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I
SS
N:
2088
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I
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2021
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3153
3152
5.
CO
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p
er
i
m
e
n
t,
3
d
if
f
er
en
t
n
et
w
o
r
k
s
ar
e
p
lan
n
ed
r
an
d
o
m
l
y
th
a
t
f
o
r
m
th
e
to
p
o
lo
g
ies
t
h
at
o
u
r
ex
p
an
s
io
n
m
o
d
el
p
er
f
o
r
m
s
m
o
d
i
f
icatio
n
s
o
n
.
T
h
en
f
o
r
ea
ch
o
f
t
h
e
to
p
o
lo
g
ies,
1
5
,
1
0
,
an
d
5
s
w
i
tch
e
s
ar
e
r
em
o
v
ed
f
r
o
m
t
h
e
n
et
w
o
r
k
a
n
d
5
,
1
0
,
an
d
1
5
s
w
itc
h
e
s
ar
e
ad
d
ed
to
th
e
n
et
w
o
r
k
b
ef
o
r
e
ex
p
a
n
s
io
n
i
s
r
u
n
.
T
h
e
r
esu
lt
s
o
f
t
h
e
o
p
tim
a
l
s
o
l
u
tio
n
s
s
h
o
w
th
a
t
r
e
m
o
v
i
n
g
ite
m
s
f
r
o
m
t
h
e
n
et
w
o
r
k
is
in
e
x
p
en
s
i
v
e
i
n
co
s
t
an
d
ti
m
e.
Ho
w
e
v
er
,
w
h
e
n
ad
d
in
g
5
,
1
0
an
d
1
5
s
w
itc
h
e
s
to
th
e
n
et
w
o
r
k
,
th
e
s
o
lu
tio
n
t
i
m
e
a
n
d
co
s
t
o
f
t
h
e
n
et
w
o
r
k
i
n
cr
ea
s
e
s
.
Ho
w
e
v
er
,
w
h
e
n
s
w
itc
h
es
ar
e
ad
d
ed
,
to
ex
p
an
d
th
e
n
et
w
o
r
k
,
th
e
s
o
lv
er
ta
k
es
ti
m
e
b
u
t
it
is
a
q
u
ic
k
o
p
er
atio
n
.
Th
e
tim
e
to
ex
p
a
n
d
an
ex
i
s
ti
n
g
n
et
w
o
r
k
b
y
ad
d
in
g
1
5
s
w
i
tch
es
r
an
g
e
s
f
r
o
m
1
to
4
s
e
c
o
n
d
s
.
T
h
e
c
o
s
t
o
f
t
h
e
s
o
l
u
t
i
o
n
s
d
e
p
e
n
d
s
o
n
w
h
e
t
h
e
r
a
n
e
x
i
s
t
i
n
g
i
t
e
m
i
s
r
e
a
l
l
o
c
a
t
e
d
,
i
f
s
o
,
t
h
e
o
p
t
i
m
a
l
s
o
l
u
t
i
o
n
c
o
s
t
i
s
m
u
c
h
m
o
r
e
e
x
p
en
s
iv
e.
T
h
e
s
ec
o
n
d
ex
p
an
s
io
n
e
x
p
er
im
en
t
i
n
v
o
l
v
es
i
n
ad
d
in
g
a
s
et
o
f
s
w
itc
h
e
s
to
an
e
x
is
tin
g
to
p
o
lo
g
y
w
it
h
th
e
co
s
t
to
r
em
o
v
e
th
e
ex
i
s
ti
n
g
in
v
en
to
r
y
th
at
s
tar
t
s
at
1
0
0
t
i
m
es
t
h
e
p
lan
n
in
g
co
s
t
an
d
g
o
es
d
o
w
n
to
1
o
f
th
e
p
lan
n
i
n
g
co
s
t
s
.
Fro
m
t
h
e
r
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u
lts
,
w
e
o
b
s
er
v
e
t
h
at
t
h
e
o
p
ti
m
al
s
o
lu
tio
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w
h
e
n
t
h
e
r
e
m
o
v
al
co
s
t
o
f
th
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ex
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s
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y
is
1
0
0
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th
e
e
x
i
s
ti
n
g
n
et
w
o
r
k
is
n
o
t
c
h
a
n
g
ed
at
all.
A
co
n
tr
o
ller
i
s
p
lace
d
f
o
r
th
e
ad
d
itio
n
al
s
w
i
tch
e
s
th
at
w
er
e
ad
d
ed
.
A
s
th
e
co
s
t
to
r
em
o
v
e
ex
is
ti
n
g
in
v
en
to
r
y
d
ec
r
ea
s
ed
,
th
e
ex
is
tin
g
n
et
w
o
r
k
s
tar
ted
ch
an
g
in
g
an
d
th
e
o
p
ti
m
al
s
o
l
u
tio
n
co
s
t
also
d
ec
r
ea
s
ed
.
Fu
r
th
er
m
o
r
e,
th
e
co
s
t
to
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e
m
o
v
e
ex
is
ti
n
g
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n
v
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to
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y
d
ec
r
ea
s
ed
,
ch
an
g
es
to
t
h
e
ex
i
s
tin
g
n
et
w
o
r
k
b
ec
a
m
e
m
o
r
e
f
r
eq
u
e
n
t.
Fo
r
f
u
t
u
r
e
w
o
r
k
,
th
i
s
w
o
r
k
ca
n
b
e
ex
p
an
d
ed
to
ap
p
ly
m
o
r
e
ad
v
an
ce
d
h
e
u
r
is
tic
al
g
o
r
ith
m
s
s
u
c
h
as
T
ab
u
se
ar
c
h
.
T
h
is
w
o
u
ld
h
e
lp
th
e
a
lg
o
r
i
th
m
p
ass
th
e
lo
ca
l
m
i
n
i
m
u
m
a
n
d
f
i
n
d
s
o
lu
tio
n
s
t
h
at
ar
e
clo
s
er
to
th
e
o
p
ti
m
al
s
o
lu
tio
n
.
RE
F
E
R
E
NC
E
S
[1
]
N.
F
e
a
m
ste
r
a
n
d
R.
Je
n
n
if
e
r,
"
T
h
e
ro
a
d
t
o
S
DN
,
A
n
in
tellec
tu
a
l
h
i
sto
ry
o
f
p
ro
g
ra
m
m
a
b
le
n
e
tw
o
rk
s
,
"
ACM
Qu
e
u
e
,
v
o
l.
1
1
,
n
o
.
1
2
,
p
p
.
2
0
-
2
2
,
2
0
1
3
.
[2
]
N.
M
c
Ke
o
w
n
e
t
a
l
.
,
"
Op
e
n
F
lo
w
:
e
n
a
b
li
n
g
in
n
o
v
a
ti
o
n
i
n
c
a
m
p
u
s
n
e
t
w
o
rk
s,"
ACM
S
IGCO
M
M
Co
mp
u
ter
Co
mm
u
n
ica
ti
o
n
Rev
iew
, v
o
l.
3
8
,
n
o
.
2
,
p
p
.
6
9
-
7
4
,
2
0
0
8
.
[3
]
B.
He
ll
e
r
e
t
a
l
.
,
"
T
h
e
c
o
n
tro
ll
e
r
p
lac
e
m
e
n
t
p
ro
b
lem
,
"
P
ro
c
e
e
d
in
g
s
o
f
th
e
fi
rs
t
wo
rk
sh
o
p
o
n
Ho
t
to
p
ics
in
so
ft
wa
re
d
e
fi
n
e
d
Ne
tw
o
rk
s
,
2
0
1
2
,
p
p
.
7
-
12
.
[4
]
M
.
F
.
Ba
ri
e
t
a
l
.
,
"
Dy
n
a
m
i
c
c
o
n
tr
o
ll
e
r
p
r
o
v
isio
n
i
n
g
i
n
so
f
tw
a
re
d
e
f
in
e
d
n
e
tw
o
rk
s,"
P
r
o
c
e
e
d
i
n
g
s
o
f
t
h
e
9
t
h
I
n
t
e
r
n
a
t
i
o
n
a
l
C
o
n
f
e
r
e
n
c
e
o
n
N
e
t
w
o
r
k
a
n
d
S
e
r
v
i
c
e
M
a
n
a
g
e
m
e
n
t
(
C
N
S
M
2
0
1
3
)
,
Z
u
r
i
c
h
,
S
w
i
t
z
e
r
l
a
n
d
,
2
0
1
3
,
p
p
.
1
8
-
25.
[5
]
Y.
N.
Hu
e
t
a
l
.
,
"
On
th
e
p
lac
e
m
e
n
t
o
f
c
o
n
tro
l
ler
s
in
so
f
tw
a
r
e
-
d
e
f
in
e
d
n
e
tw
o
rk
s,
"
T
h
e
J
o
u
rn
a
l
o
f
Ch
i
n
a
U
n
ive
rs
it
ies
o
f
P
o
sts a
n
d
T
e
lec
o
mm
u
n
ica
ti
o
n
s
,
v
o
l.
1
9
,
n
o
.
2
,
p
p
.
9
2
-
1
7
1
,
2
0
1
2
.
[6
]
J.
I.
Na
se
r
a
n
d
A
.
J.
K
a
d
h
im
,
"
M
u
lt
ica
st
ro
u
ti
n
g
stra
teg
y
f
o
r
S
DN
-
c
lu
ste
r
b
a
se
d
M
A
NE
T
,
"
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
El
e
c
trica
l
a
n
d
C
o
mp
u
ter
En
g
in
e
e
rin
g
(
IJ
ECE
)
,
v
o
l.
1
0
,
n
o
.
5
,
p
p
.
4
4
4
7
-
4
4
5
7
,
2
0
2
0
.
[7
]
L
.
Ya
n
g
e
t
a
l
.
,
"
F
o
rw
a
rd
in
g
a
n
d
c
o
n
tr
o
l
e
lem
e
n
t
se
p
a
ra
ti
o
n
(f
o
rc
e
s) f
ra
m
e
w
o
rk
,
"
RF
C3
7
4
6
,
p
p
.
5
-
3
0
,
2
0
0
4
.
[8
]
J.
M
e
d
v
e
d
e
t
a
l
.,
“
Op
e
n
d
a
y
li
g
h
t:
T
o
wa
rd
s
a
m
o
d
e
l
-
d
ri
v
e
n
sd
n
c
o
n
tro
ll
e
r
a
rc
h
it
e
c
tu
re
,
”
Pro
c
e
e
d
in
g
o
f
IEE
E
In
ter
n
a
t
io
n
a
l
S
y
mp
o
si
u
m o
n
a
W
o
rld
o
f
W
ire
les
s,
M
o
b
il
e
a
n
d
M
u
lt
ime
d
ia
Ne
two
rk
s 2
0
1
4
,
S
y
d
n
e
y
,
NSW
,
A
u
stra
li
a
,
2
0
1
4
,
p
p
.
1
-
6.
[9
]
B.
Nu
n
e
s
e
t
a
l
.
,
"
A
su
rv
e
y
o
f
so
ftw
a
r
e
-
d
e
f
in
e
d
n
e
t
w
o
rk
in
g
:
P
a
st,
p
re
se
n
t,
a
n
d
f
u
tu
re
o
f
p
ro
g
ra
m
m
a
b
le
n
e
tw
o
rk
s,
"
IEE
E
Co
mm
u
n
ica
t
io
n
s S
u
rv
e
y
s
&
T
u
t
o
ria
ls
,
v
o
l.
1
6
,
n
o
.
3
,
p
p
.
1
6
1
7
-
1
6
3
4
,
2
0
1
4
.
[1
0
]
M
.
Kin
d
e
t
a
l
.
,
"
S
p
li
t
a
rc
h
it
e
c
tu
r
e
:
A
p
p
l
y
in
g
th
e
so
f
t
w
a
re
d
e
f
in
e
n
e
tw
o
rk
i
n
g
c
o
n
c
e
p
t
to
c
a
rrier
n
e
tw
o
rk
s,
"
W
o
rld
T
e
lec
o
mm
u
n
ica
ti
o
n
s C
o
n
g
re
ss
(W
T
C),
p
p
.
1
-
6
,
2
0
1
2
.
[1
1
]
B.
He
ll
e
r,
"
T
h
e
c
o
n
tro
ll
e
r
p
lac
e
m
e
n
t
p
ro
b
le
m,
"
ACM
S
IGCO
M
M
Co
mp
u
ter
Co
mm
u
n
ica
ti
o
n
Rev
iew
,
v
o
l.
4
2
,
n
o
.
4
,
p
p
.
4
7
3
-
4
7
8
,
2
0
1
4
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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t J
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&
C
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p
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N:
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8708
Op
timiz
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p
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t in
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2
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L
.
L
i
e
t
a
l
.
,
"
T
o
wa
rd
so
f
twa
re
-
d
e
f
in
e
d
c
e
ll
u
lar
n
e
tw
o
rk
s,"
2
0
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2
Eu
ro
p
e
a
n
W
o
rk
sh
o
p
o
n
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o
f
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rk
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g
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rm
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e
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m
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n
y
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2
0
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2
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p
p
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2
.
[1
3
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D.
V
e
n
m
a
n
i,
"
De
m
y
stify
in
g
li
n
k
c
o
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g
e
stio
n
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n
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-
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f
lo
w
,
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0
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2
5
t
h
In
ter
n
a
ti
o
n
a
l
Co
n
fer
e
n
c
e
o
n
Ne
w
T
e
c
h
n
o
l
o
g
ies
,
M
o
b
i
li
ty a
n
d
S
e
c
u
rity (
NT
M
S
)
,
Ista
n
b
u
l,
T
u
rk
e
y
,
2
0
1
2
,
p
p
.
1
-
8.
[1
4
]
T
.
L
u
o
e
t
a
l
.
,
"
S
e
n
so
r
o
p
e
n
f
lo
w:
En
a
b
li
n
g
so
f
t
w
a
re
-
d
e
f
in
e
d
w
irele
ss
s
e
n
so
r
n
e
tw
o
rk
s,"
IEE
E
C
o
mm
u
n
ic
a
ti
o
n
s
L
e
tt
e
rs
,
v
o
l.
1
6
,
n
o
.
1
1
,
p
p
.
1
8
9
6
-
1
8
9
9
,
2
0
1
2
.
[1
5
]
D.
S
im
e
o
n
id
o
u
e
t
a
l
.
,
"
E
n
a
b
li
n
g
t
h
e
f
u
tu
re
o
p
ti
c
a
l
i
n
tern
e
t
w
it
h
o
p
e
n
f
lo
w
:
A
p
a
ra
d
ig
m
sh
if
t
in
p
ro
v
i
d
in
g
i
n
telli
g
e
n
t
o
p
ti
c
a
l
n
e
tw
o
rk
se
rv
ice
s,"
2
0
1
1
1
3
th
In
ter
n
a
ti
o
n
a
l
C
o
n
fer
e
n
c
e
o
n
T
ra
n
sp
a
re
n
t
Op
t
ica
l
Ne
tw
o
r
k
s
,
S
to
c
k
h
o
lm
,
S
w
e
d
e
n
,
2
0
1
1
,
p
p
.
1
-
4.
[1
6
]
S
.
G
rin
g
e
ri,
"
Ex
ten
d
in
g
so
f
t
wa
re
d
e
f
in
e
d
n
e
t
w
o
rk
p
rin
c
ip
les
to
in
c
lu
d
e
o
p
ti
c
a
l
tran
sp
o
rt,
"
IEE
E
Co
mm
u
n
ic
a
ti
o
n
s
M
a
g
a
zin
e
,
v
o
l.
5
1
,
n
o
.
3
,
p
p
.
3
2
-
4
0
,
2
0
1
3
.
[1
7
]
M
.
S
h
iraz
ip
o
u
r
e
t
a
l
.
"
Op
e
n
f
lo
w
a
n
d
m
u
lt
i
-
lay
e
r
e
x
ten
sio
n
s:
Ov
e
r
v
ie
w
a
n
d
n
e
x
t
ste
p
s,"
2
0
1
2
Eu
r
o
p
e
a
n
W
o
rk
sh
o
p
o
n
S
o
f
twa
re
De
fi
n
e
d
Ne
two
r
k
in
g
,
Da
r
m
sta
d
t,
G
e
r
m
a
n
y
,
2
0
1
2
,
p
p
.
1
3
-
1
7
.
[1
8
]
S
.
Da
s
e
t
a
l
.
,
"
P
a
c
k
e
t
a
n
d
c
irc
u
it
n
e
t
w
o
rk
c
o
n
v
e
rg
e
n
c
e
w
it
h
o
p
e
n
f
lo
w
,
"
2
0
1
0
Co
n
fer
e
n
c
e
o
n
Op
ti
c
a
l
Fi
b
e
r
Co
mm
u
n
ica
ti
o
n
(
OFC/NF
OEC),
c
o
ll
o
c
a
ted
N
a
ti
o
n
a
l
F
ib
e
r
Op
t
i
c
En
g
i
n
e
e
rs
Co
n
fer
e
n
c
e
,
S
a
n
Di
e
g
o
,
CA
,
USA
,
2
0
1
0
,
p
p
.
1
-
3.
[1
9
]
Qu
in
tero
-
D
u
ra
n
,
M
.
,
Ca
n
d
e
l
o
-
Be
c
e
rra
,
J.
E.
,
a
n
d
S
o
t
o
-
Ortiz,
J.
D.,
“
A
m
o
d
if
i
e
d
b
a
c
k
w
a
rd
/
f
o
rw
a
r
d
sw
e
e
p
-
b
a
se
d
m
e
th
o
d
f
o
r
re
c
o
n
f
ig
u
ra
ti
o
n
o
f
u
n
b
a
lan
c
e
d
d
istr
ib
u
ti
o
n
n
e
tw
o
rk
s,
”
In
ter
n
a
t
io
n
a
l
J
o
u
rn
a
l
o
f
E
lec
trica
l
a
n
d
C
o
mp
u
ter
En
g
i
n
e
e
rin
g
(
IJ
ECE
)
,
v
o
l.
9
,
n
o
.
1
,
p
p
.
85
-
1
0
1
,
2
0
1
9
.
[2
0
]
M
.
S
h
iraz
ip
o
u
r
e
t
a
l
.
,
"
Re
a
li
z
in
g
p
a
c
k
e
t
o
p
ti
c
a
l
in
teg
ra
ti
o
n
w
it
h
sd
n
a
n
d
o
p
e
n
f
lo
w
1
.
1
e
x
ten
sio
n
s,"
2
0
1
2
IEE
E
In
ter
n
a
t
io
n
a
l
C
o
n
fer
e
n
c
e
o
n
C
o
mm
u
n
ica
t
io
n
s (
ICC)
,
Ottaw
a
,
ON
,
Ca
n
a
d
a
,
2
0
1
2
,
p
p
.
6
6
3
3
-
6
6
3
7
.
[2
1
]
M
.
Ch
a
n
n
e
g
o
w
d
a
e
t
a
l
.,
"
Ex
p
e
rime
n
tal
e
v
a
lu
a
ti
o
n
o
f
e
x
ten
d
e
d
Op
e
n
F
lo
w
d
e
p
lo
y
m
e
n
t
f
o
r
h
ig
h
-
pe
rfo
rm
a
n
c
e
o
p
ti
c
a
l
n
e
tw
o
rk
s,"
2
0
1
2
3
8
t
h
Eu
r
o
p
e
a
n
Co
n
fer
e
n
c
e
a
n
d
Exh
ib
it
io
n
o
n
Op
ti
c
a
l
Co
mm
u
n
ica
ti
o
n
s
,
A
m
ste
rd
a
m
,
N
e
th
e
rlan
d
s,
2
0
1
2
,
p
p
.
1
-
3.
[2
2
]
N.
Ha
n
d
ig
o
l,
"
W
h
e
re
is t
h
e
d
e
b
u
g
g
e
r
f
o
r
m
y
so
f
t
w
a
r
e
-
d
e
f
in
e
d
n
e
two
rk
,
"
Pro
c
e
e
d
in
g
s o
f
t
h
e
1
st Ho
t
S
DN W
o
rk
sh
o
p
,
2
0
1
2
,
p
p
.
5
5
-
60
.
[2
3
]
Ca
n
in
i,
M
a
rc
o
,
a
n
d
De
jan
K
o
stic,
"
S
y
ste
m
a
ti
c
S
o
f
t
w
a
re
Tes
ti
n
g
M
e
e
ts
Ne
t
w
o
rk
in
g
,”
Co
n
fer
e
n
c
e
O
p
e
n
Ne
two
rk
in
g
S
u
mm
it
,
Res
e
a
rc
h
T
ra
c
k
(
ONS
)
,
2
0
1
3
,
p
p
.
1
-
2
.
[2
4
]
M
.
K.
S
h
in
e
t
a
l
.
,
"
V
e
riS
DN
:
F
o
rm
a
l
v
e
ri
f
ica
ti
o
n
f
o
r
so
f
t
w
a
re
d
e
f
in
e
d
n
e
t
w
o
rk
in
g
(S
DN
),
"
T
e
l
e
c
o
mm
u
n
ica
t
io
n
Rev
iew
,
p
p
.
1
-
2
,
2
0
1
3
.
[2
5
]
B.
L
a
n
tz
e
t
a
l
.
,
"
A
n
e
tw
o
rk
in
a
lap
to
p
:
ra
p
id
p
ro
to
ty
p
in
g
f
o
r
so
f
tw
a
r
e
-
d
e
f
in
e
d
n
e
t
w
o
rk
s,
"
Pro
c
e
e
d
in
g
s
o
f
th
e
1
0
th
ACM
W
o
rk
sh
o
p
o
n
H
o
t
T
o
p
ics
i
n
N
e
two
rk
s.
Ho
tNets 2
0
1
0
,
M
o
n
ter
e
y
,
CA
,
US
A
,
p
p
.
1
9
-
2
6
,
2
0
1
0
.
[2
6
]
P
.
G
u
im
a
r
a
e
s
e
t
a
l
.
,
"
Ex
p
e
rim
e
n
ti
n
g
c
o
n
te
n
t
-
c
e
n
tri
c
n
e
tw
o
rk
s
in
th
e
f
u
tu
re
i
n
tern
e
t
tes
tb
e
d
e
n
v
ir
o
n
m
e
n
t,
"
2
0
1
3
IEE
E
In
ter
n
a
ti
o
n
a
l
C
o
n
fer
e
n
c
e
o
n
Co
mm
u
n
ica
t
io
n
s W
o
rk
sh
o
p
s
(
ICC),
Bu
d
a
p
e
st,
Hu
n
g
a
r
y
,
2
0
1
3
,
p
p
.
1
3
8
3
-
1
3
8
7
.
[2
7
]
B
.
B.
Be
z
a
b
e
h
a
n
d
A
.
D.
M
e
n
g
istu
,
"
T
h
e
e
ff
e
c
ts
o
f
m
u
lt
ip
le
lay
e
rs
f
e
e
d
-
f
o
r
w
a
rd
n
e
u
ra
l
n
e
tw
o
rk
tran
sf
e
r
f
u
n
c
ti
o
n
i
n
d
ig
it
a
l
b
a
se
d
Et
h
i
o
p
ia
n
so
il
c
las
sif
ic
a
ti
o
n
a
n
d
m
o
istu
re
p
re
d
ict
io
n
,
"
In
ter
n
a
ti
o
n
a
l
J
o
u
r
n
a
l
o
f
El
e
c
trica
l
a
n
d
Co
mp
u
ter
E
n
g
in
e
e
rin
g
(
IJ
ECE
)
, v
o
l.
1
0
,
n
o
.
4
,
p
p
.
4
0
7
3
-
4
0
7
9
,
2
0
2
0
.
[2
8
]
H.
A
tt
ia,
"
A
rti
f
ici
a
l
n
e
u
ra
l
n
e
tw
o
rk
-
b
a
se
d
u
n
it
y
p
o
w
e
r
fa
c
to
r
c
o
rre
c
to
r
f
o
r
s
in
g
le
p
h
a
se
DC
-
DC
c
o
n
v
e
rters
,
"
In
ter
n
a
t
io
n
a
l
J
o
u
rn
a
l
o
f
E
lec
trica
l
a
n
d
C
o
mp
u
ter
En
g
in
e
e
rin
g
(
IJ
ECE
)
, v
o
l.
1
0
,
n
o
.
4
,
p
p
.
4
1
4
5
-
4
1
5
4
,
2
0
2
0
.
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