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2722
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w
t
e
c
h
nol
o
gy
for
a
c
hi
e
v
i
ng
t
h
e
i
r
d
e
m
a
nd
fo
r
f
a
s
t
a
c
c
e
s
s
a
nd
s
t
or
a
ge
a
nd
c
l
oud
c
om
put
i
ng
is
one
of
t
h
e
m
.
D
u
e
to
t
h
e
hu
ge
da
t
a
s
t
ora
g
e
a
nd
p
roc
e
s
s
i
ng
t
i
m
e
c
a
pa
c
i
t
y
c
l
o
ud
c
om
p
ut
i
ng
g
a
i
ns
m
u
c
h
a
t
t
e
nt
i
on
in
di
ff
e
re
nt
fi
e
l
d
of
l
i
f
e
.
F
ur
t
he
rm
or
e
,
t
hi
s
t
e
c
hn
ol
ogy
a
i
m
s
to
provi
de
r
e
l
i
a
b
l
e
a
nd
c
us
t
om
i
z
e
d
qua
l
i
t
y
of
s
e
rv
i
c
e
for
e
nd
-
us
e
r
de
m
a
n
d.
It
is
a
c
on
c
e
p
t
t
h
a
t
o
f
fe
rs
a
dy
na
m
i
c
a
l
l
y
s
c
a
l
a
bl
e
r
e
s
ourc
e
for
t
he
us
e
r
in
a
s
p
e
c
i
fi
c
t
i
m
e
w
i
t
h
t
he
h
e
l
p
of
i
n
t
e
rne
t
[4]
.
F
i
gu
re
1
s
h
o
w
s
t
he
s
t
a
nd
a
rd
c
l
oud
c
o
m
pu
t
i
ng
s
t
ruc
t
ur
e
w
he
r
e
it
s
how
s
di
f
fe
r
e
nt
de
v
i
c
e
a
r
e
c
onne
c
t
e
d
w
i
t
h
d
a
t
a
c
e
nt
e
r.
T
h
e
s
e
di
ffe
r
e
nt
de
v
i
c
e
a
n
d
e
l
e
m
e
n
t
a
r
e
d
i
vi
d
e
d
i
nt
o
t
w
o
m
a
i
n
s
e
c
t
i
o
ns
w
hi
c
h
a
re
a
c
c
e
s
s
or
a
nd
p
rovi
de
r
.
T
he
r
ol
e
s
of
a
c
c
e
s
s
or
a
re
to
s
h
a
re
a
nd
c
o
l
l
e
c
t
da
t
a
f
rom
da
t
a
c
e
nt
e
r.
T
he
rol
e
s
of
prov
i
de
r
a
r
e
to
p
rovi
de
di
ff
e
re
nt
ki
nd
of
s
e
rvi
c
e
s
in
t
h
e
for
m
of
h
a
rdw
a
re
a
nd
s
oft
w
a
r
e
to
t
h
e
c
l
oud
d
a
t
a
c
e
nt
e
r
w
he
r
e
da
t
a
c
e
n
t
e
r
c
on
t
rol
a
l
l
t
h
e
s
e
a
c
t
i
vi
t
i
e
s
.
C
l
oud
c
o
m
pu
t
i
n
g
a
r
c
hi
t
e
c
t
ur
e
c
om
p
ri
s
e
s
of
t
w
o
m
a
i
n
p
a
rt
s
w
h
i
c
h
a
r
e
fr
ont
e
nd
a
n
d
b
a
c
k
e
nd
w
h
e
re
di
f
fe
r
e
nt
c
o
m
pon
e
n
t
s
in
t
e
rm
of
s
t
ora
g
e
,
run
t
i
m
e
,
s
e
rv
i
c
e
a
nd
s
e
c
uri
t
y
w
ork
in
b
a
c
k
-
e
nd
a
p
pl
i
c
a
t
i
on
a
nd
s
e
rvi
c
e
w
or
k
in
fron
t
e
nd
.
Cl
ou
d
a
rc
h
i
t
e
c
t
ure
not
o
nl
y
d
e
fi
ne
s
t
h
e
c
om
p
one
n
t
s
but
als
o
t
he
r
e
l
a
t
i
ons
h
i
p
be
t
w
e
e
n
t
h
e
m
.
T
he
s
e
c
o
m
pon
e
n
t
s
a
r
e
c
onn
e
c
t
e
d
w
i
t
h
e
a
c
h
o
t
h
e
r
w
i
t
h
t
h
e
h
e
l
p
of
i
nt
e
rne
t
[5]
.
F
i
gur
e
1
pr
e
s
e
n
t
s
t
h
e
grow
t
h
of
di
ff
e
re
nt
t
e
c
hno
l
ogi
e
s
as
c
om
p
a
re
d
w
i
t
h
CC
.
F
i
gure
1
pr
e
s
e
n
t
s
t
h
e
grow
t
h
of
di
ff
e
r
e
nt
t
e
c
hno
l
og
i
e
s
c
om
pa
re
d
to
CC
;
t
he
r
e
for
e
,
t
h
e
c
l
oud
ne
e
ds
to
c
ha
n
ge
its
m
od
e
l
a
n
d
i
m
pro
ve
di
ff
e
re
nt
l
a
ye
rs
a
nd
s
t
ru
c
t
ur
e
s
.
T
hus
,
v
a
ri
ous
re
s
e
a
r
c
he
rs
[6]
pre
s
e
nt
a
ne
w
m
ode
l
of
c
l
o
ud
c
o
m
put
i
ng
know
n
as
s
ky
c
om
put
i
ng
to
ove
rc
om
e
t
he
d
i
ffe
r
e
n
t
i
s
s
u
e
s
f
a
c
e
d
by
c
l
o
ud
s
t
ruc
t
ure
.
T
he
na
m
e
of
s
ky
c
o
m
put
i
ng
w
a
s
pre
s
e
nt
e
d
by
c
o
i
ne
d
b
a
c
k
in
2008
.
A
c
c
ord
i
ng
to
h
i
m
,
m
ul
t
i
-
c
l
ou
d
c
om
p
ut
i
ng
is
group
e
d
in
t
h
e
e
nvi
ro
nm
e
nt
.
It
a
ddr
e
s
s
e
s
t
h
e
provi
d
e
r
i
nt
e
rop
e
ra
bi
l
i
t
y
a
n
d
c
l
oud
prov
i
de
r
in
a
group
for
m
[7]
.
It
ha
s
b
e
e
n
s
e
rvi
ng
s
i
n
c
e
20
08
by
s
h
a
ri
n
g
t
he
k
now
l
e
dg
e
of
how
t
he
g
l
ob
a
l
a
nd
l
oc
a
l
re
s
ourc
e
s
a
re
m
a
na
ge
d
l
i
ke
bi
g
da
t
a
,
w
or
ks
pa
c
e
,
a
nd
t
ra
ns
form
a
t
i
o
n
of
he
l
p
f
rom
a
t
r
a
di
t
i
on
a
l
s
ys
t
e
m
to
IT
l
a
nds
c
a
p
e
in
t
h
e
for
m
of
s
k
y
c
o
m
pu
t
i
n
g.
B
e
t
t
e
r
a
do
pt
i
on
a
nd
m
i
gr
a
t
i
on
in
t
h
e
S
ky
c
o
m
put
i
ng
m
od
e
l
a
r
e
pe
rfor
m
e
d
[8]
.
F
or
t
h
a
t
r
e
a
s
o
n,
in
t
hi
s
pa
p
e
r,
we
pre
s
e
nt
t
h
e
s
ky
c
om
put
i
ng
m
od
e
l
a
nd
its
di
ff
e
re
nt
l
a
y
e
rs
,
w
hi
c
h
a
r
e
pre
s
e
nt
e
d
by
va
r
i
ous
r
e
s
e
a
rc
he
rs
a
nd
s
u
m
m
a
ri
z
e
s
om
e
of
t
h
e
re
l
a
t
e
d
w
ork
a
b
out
s
ky
c
o
m
put
i
ng
.
F
i
g
ure
1.
G
row
t
h
of
t
e
c
hno
l
ogi
e
s
2.
P
A
P
ER
C
O
N
TR
I
BU
TI
O
N
T
hi
s
s
e
c
t
i
o
n
h
i
gh
l
i
gh
t
s
t
he
c
o
nt
r
i
but
i
on
m
a
d
e
by
t
he
a
u
t
hors
in
t
hi
s
pa
p
e
r
.
T
h
e
p
a
pe
r
m
a
i
nl
y
a
i
m
s
to
pre
s
e
n
t
t
he
c
l
oud
c
o
m
pu
t
i
ng
i
s
s
u
e
s
s
t
ru
c
t
ure
a
nd
pr
e
s
e
n
t
i
nf
orm
a
t
i
o
n
a
bou
t
t
he
ne
w
m
o
de
l
of
CC
,
k
now
n
as
s
ky
c
om
put
i
ng
,
a
nd
s
o
m
e
re
l
a
t
e
d
w
or
k
a
b
out
t
hi
s
n
e
w
m
ode
l
.
O
ur
m
a
i
n
c
ont
r
i
but
i
ons
of
t
he
pa
p
e
r
a
re
s
um
m
a
ri
z
e
d
as
:
−
To
f
i
nd
ou
t
l
i
t
e
r
a
t
ur
e
a
bou
t
s
k
y
c
om
put
i
ng
.
−
To
d
e
f
i
ne
t
h
e
s
t
ru
c
t
ur
e
of
s
ky
c
om
p
ut
i
ng.
−
To
d
e
t
e
r
m
i
n
e
t
he
up
c
o
m
i
ng
i
m
por
t
a
nc
e
of
s
ky
c
o
m
pu
t
i
n
g.
−
F
ut
ure
i
s
s
ue
s
r
e
ga
rd
i
ng
s
ky
c
o
m
pu
t
i
ng
.
3.
D
I
F
F
ER
EN
T
TEC
H
N
O
LO
G
I
ES
In
t
h
i
s
s
e
c
t
i
on,
we
e
xp
l
a
i
n
s
o
m
e
ba
s
i
c
c
onc
e
p
t
s
a
b
out
di
ff
e
r
e
nt
c
o
m
put
i
ng
a
nd
c
o
m
p
a
re
t
h
e
m
w
i
t
h
s
ky
c
om
put
i
ng
.
F
og
Com
pu
t
i
ng
:
It
i
s
c
l
os
e
r
t
o
t
h
e
t
hi
ngs
t
h
a
t
pro
duc
e
a
c
t
i
on
on
IoT
da
t
a
t
he
s
e
de
v
i
c
e
s
a
r
e
c
a
l
l
e
d
fog
node
s
.
T
he
s
e
nod
e
s
c
a
n
b
e
de
ve
l
ope
d
a
n
yw
he
r
e
w
i
t
h
a
n
e
t
w
ork
c
o
n
ne
c
t
i
on.
A
ny
d
e
vi
c
e
c
on
t
a
i
ni
n
g
c
om
p
ut
e
r
s
t
or
a
g
e
a
n
d
ne
t
w
ork
c
onn
e
c
t
i
v
i
t
y
c
a
n
b
e
c
a
l
l
e
d
a
fog
c
o
m
put
e
r
,
s
uc
h
a
s
ro
ut
e
r
s
w
i
t
c
he
s
a
nd
e
m
b
e
dd
e
d
s
e
rve
rs
[9]
.
F
i
gur
e
2
s
how
s
t
h
e
f
og
s
t
ruc
t
ur
e
w
i
t
h
t
he
di
f
fe
r
e
nt
d
e
vi
c
e
s
.
Evaluation Warning : The document was created with Spire.PDF for Python.
IS
S
N
:
2722
-
3221
Com
pu
t
S
c
i
Inf
T
e
c
h
nol
,
V
o
l
.
6
,
N
o
.
3
,
N
ov
e
m
be
r
20
25
:
294
-
306
296
F
i
g
ure
2
.
S
t
ruc
t
ure
of
f
og
c
om
p
ut
i
ng
F
og
c
o
m
pu
t
i
ng
i
s
i
n
t
e
l
l
i
ge
n
t
i
n
t
he
l
o
c
a
l
a
re
a
.
It
t
r
a
ns
m
i
t
s
da
t
a
t
o
t
h
e
e
ndpo
i
nt
t
o
t
h
e
g
a
t
e
w
a
y
w
h
e
re
i
t
pro
c
e
s
s
e
s
a
nd
t
he
n
s
e
nds
i
t
t
o
t
he
t
ra
ns
m
i
s
s
i
on
kn
ow
n
a
s
f
og
c
om
p
ut
i
ng
[10]
.
T
h
e
di
ff
e
re
nt
s
e
ns
or
nod
e
i
s
us
e
d
i
n
a
f
og
f
or
s
e
ns
i
ng
pur
pos
e
,
w
h
i
c
h
c
a
n
i
n
t
e
r
c
onn
e
c
t
t
h
e
d
e
vi
c
e
.
T
h
e
s
e
ns
ors
s
upp
ort
a
d
di
t
i
on
a
l
i
m
a
g
e
s
from
t
he
l
oc
a
l
a
re
a
.
S
e
ns
or
nod
e
s
a
r
e
s
m
a
l
l
a
nd
l
i
m
i
t
e
d
i
n
proc
e
s
s
i
ng
a
nd
c
a
n
m
e
a
s
ure
a
nd
c
om
b
i
n
e
i
nfor
m
a
t
i
on
fro
m
t
h
e
e
nv
i
ron
m
e
n
t
,
a
nd
t
h
e
s
e
nod
e
s
a
re
us
e
d
i
n
fo
g
c
om
put
i
ng
[11]
.
T
h
e
m
a
i
n
c
h
a
r
a
c
t
e
r
of
fog
c
o
m
put
i
ng
i
s
l
ow
l
a
t
e
nc
y
l
o
c
a
t
i
on
a
w
a
r
e
n
e
s
s
a
nd
m
ob
i
l
i
t
y
v
e
ry
l
a
rg
e
num
be
r
o
f
n
od
e
s
a
re
us
e
d
.
It
i
s
i
m
p
l
e
m
e
n
t
e
d
a
t
t
he
e
dge
of
t
he
n
e
t
w
ork
a
nd
prov
i
d
e
s
l
oc
a
t
i
on
a
w
a
re
n
e
s
s
,
qu
a
l
i
t
y
of
s
e
rv
i
c
e
s
for
re
a
l
-
t
i
m
e
s
e
rvi
c
e
s
[1
2]
.
G
r
i
d
Com
put
i
ng
:
Is
t
he
s
t
e
p
of
a
di
f
fe
r
e
nt
proc
e
s
s
or
a
r
c
hi
t
e
c
t
ure
t
h
a
t
c
o
m
bi
n
e
s
c
om
put
e
r
re
s
ourc
e
s
fro
m
a
d
i
ff
e
re
n
t
d
om
a
i
n
.
I
n
t
h
e
gri
d
c
o
m
pu
t
e
rs
,
t
he
t
a
s
ks
a
re
pe
r
form
e
d
t
og
e
t
h
e
r
i
n
t
he
s
a
m
e
l
i
ne
[13]
.
G
ri
d
c
om
p
ut
i
ng
i
s
d
i
s
t
ri
but
e
d
c
o
m
put
i
ng
i
n
a
n
e
nv
i
ron
m
e
n
t
w
h
i
c
h
i
s
dyn
a
m
i
c
i
n
n
a
t
ur
e
.
I
t
us
e
s
ru
nt
i
m
e
s
e
l
e
c
t
i
on
s
h
a
r
i
ng,
a
ggre
ga
t
i
on
a
nd
d
i
s
t
r
i
but
e
d
a
u
t
ono
m
o
us
re
s
our
c
e
s
ba
s
e
d
on
a
v
a
i
l
a
b
i
l
i
t
y
,
c
a
p
a
bi
l
i
t
y,
pe
rfor
m
a
nc
e
,
a
nd
c
os
t
[
14]
.
Mobi
l
e
Com
p
ut
i
ng
:
Is
t
h
e
c
o
m
put
i
n
g
de
v
i
c
e
i
n
w
hi
c
h
a
n
y
de
v
i
c
e
i
s
c
r
e
a
t
e
d
by
us
i
ng
m
obi
l
e
c
om
pon
e
nt
s
s
uc
h
a
s
m
ob
i
l
e
ha
r
dw
a
r
e
,
s
of
t
w
a
r
e
,
a
nd
op
e
r
a
t
i
ng
s
ys
t
e
m
.
It
i
s
us
e
d
for
pr
ovi
d
i
n
g
s
e
rvi
c
e
s
a
nd
a
pp
l
i
c
a
t
i
ons
[15]
.
T
he
y
a
r
e
a
l
s
o
us
e
d
for
fi
x
e
d
l
oc
a
t
i
on
a
nd
re
fe
r
t
o
a
c
c
e
s
s
m
u
l
t
i
-
l
o
c
a
t
i
on
.
T
h
e
a
ppl
i
c
a
t
i
on
of
m
obi
l
e
c
o
m
put
i
ng
t
oda
y
ha
s
b
e
c
o
m
e
u
bi
qu
i
t
ous
a
nd
pe
rva
s
i
ve
i
n
bus
i
n
e
s
s
a
nd
c
ons
um
e
r
l
oc
a
t
i
ons
.
T
he
m
a
i
n
a
dva
nt
a
ge
of
i
t
s
c
onv
e
ni
e
nc
e
i
s
t
ha
t
i
t
a
l
l
ow
s
a
us
e
r
t
o
a
c
c
e
s
s
a
ny
t
i
m
e
a
nd
g
e
t
s
i
nfor
m
a
t
i
on
fr
om
a
nyw
he
r
e
[16]
.
It
c
ons
i
s
t
s
of
w
i
r
e
l
e
s
s
n
e
t
w
ork
a
c
c
e
s
s
a
nd
us
e
s
d
i
ff
e
re
n
t
ki
n
ds
of
s
t
a
t
i
ons
t
o
s
ha
re
ph
ys
i
c
a
l
a
t
t
a
c
hm
e
nt
s
i
n
re
c
e
i
v
i
ng
s
i
gn
a
l
s
.
T
h
e
w
i
r
e
l
e
s
s
n
e
t
w
ork
i
s
us
ua
l
l
y
c
onn
e
c
t
e
d
w
i
t
h
t
he
c
o
m
put
e
r
de
vi
c
e
.
M
obi
l
e
us
e
rs
c
a
n
a
c
c
e
s
s
v
e
rs
a
t
i
l
e
c
o
m
m
uni
c
a
t
i
o
n
w
i
t
h
di
ff
e
re
nt
p
e
opl
e
[17]
.
G
r
e
e
n
Com
pu
t
i
ng
:
T
h
i
s
i
s
t
h
e
s
t
udy
a
nd
m
a
nuf
a
c
t
uri
ng
w
i
t
h
d
i
ffe
re
n
t
r
e
s
ourc
e
s
d
e
s
i
gn
e
d
a
s
fri
e
ndl
y
for
t
h
e
e
n
vi
ron
m
e
nt
.
T
he
s
e
re
s
ourc
e
s
a
r
e
d
e
s
i
gn
e
d
a
s
t
h
a
t
t
he
y
do
no
t
a
ffe
c
t
t
h
e
e
nv
i
r
onm
e
nt
.
It
i
s
ru
l
e
d
t
ha
t
i
m
p
l
e
m
e
n
t
i
n
g
c
o
m
pu
t
e
r
re
s
ourc
e
s
i
n
s
uc
h
a
w
a
y
re
duc
e
s
t
h
e
e
ne
rgy
a
nd
s
o
c
i
a
l
i
m
pa
c
t
of
t
h
e
e
nvi
ro
nm
e
nt
[18]
,
du
e
t
o
t
he
e
n
e
rgy
a
n
d
fri
e
n
dl
y
e
nv
i
ron
m
e
n
t
gr
e
e
n
c
o
m
pu
t
i
ng
ge
t
t
i
ng
m
ore
a
nd
m
ore
a
t
t
e
nt
i
on
i
n
t
he
m
od
e
rn
w
or
l
d
.
T
he
a
re
a
of
de
s
i
gn
,
d
i
s
pos
i
ng
o
f
s
e
rv
e
rs
a
nd
s
ubs
ys
t
e
m
s
l
i
k
e
m
on
i
t
or
,
p
ri
nt
e
r
a
nd
n
e
t
w
ork
i
ng
de
v
i
c
e
for
c
o
m
m
u
ni
c
a
t
i
on
s
ys
t
e
m
m
a
k
e
t
he
m
s
a
fe
a
nd
e
c
o
-
fri
e
nd
l
y
s
ys
t
e
m
[
19]
.
E
dge
Com
pu
t
i
ng
:
T
hi
s
i
s
no
t
t
he
n
e
w
c
o
nc
e
pt
w
h
e
n
s
e
ve
r
a
l
t
re
nds
a
re
c
o
m
e
t
og
e
t
h
e
r
a
nd
c
re
a
t
e
a
n
opport
u
ni
t
y
t
o
he
l
p
a
nd
run
a
m
a
s
s
i
v
e
a
m
o
unt
of
m
a
c
h
i
n
e
a
nd
d
a
t
a
i
nt
o
a
c
t
i
on
a
bl
e
a
nd
m
a
k
e
c
l
os
e
r
t
og
e
t
h
e
r
i
s
know
n
a
s
e
dg
e
c
o
m
pu
t
i
ng
.
A
n
e
dg
e
de
v
i
c
e
i
s
i
n
t
he
c
l
ou
d,
w
hi
c
h
m
a
ke
s
a
n
yt
h
i
ng
or
a
n
e
nt
r
y
poi
n
t
t
o
a
ne
t
w
ork
us
e
d
i
n
t
he
di
ff
e
re
nt
c
e
nt
e
rs
[20
]
.
It
re
f
e
rs
t
o
e
na
b
l
i
n
g
t
e
c
hnol
ogy
t
ha
t
a
l
l
ow
s
c
om
pu
t
a
t
i
o
ns
t
o
pe
rf
orm
a
t
t
he
e
dge
o
f
a
ny
n
e
t
w
o
rk
a
nd
t
o
dow
n
l
oa
d
da
t
a
from
c
l
oud
s
e
rvi
c
e
s
a
nd
ups
t
r
e
a
m
d
a
t
a
on
be
h
a
l
f
of
Io
T
s
e
r
vi
c
e
s
.
It
i
s
us
e
d
f
or
pr
om
o
t
i
ng
a
s
a
s
t
ra
t
e
g
y
t
o
a
c
hi
e
ve
hi
gh
l
y
a
v
a
i
l
e
d
w
e
b
s
e
rv
i
c
e
s
[21]
.
Sof
t
Com
put
i
ng
:
T
hi
s
i
s
a
n
e
s
s
e
nt
i
a
l
a
nd
pow
e
rfu
l
t
oo
l
us
e
d
i
n
t
h
e
phys
i
c
a
l
a
nd
c
he
m
i
c
a
l
a
r
e
a
for
gr
a
ppl
i
ng
w
i
t
h
t
he
ore
t
i
c
a
l
a
nd
a
n
a
l
y
t
i
c
a
l
prob
l
e
m
s
.
T
he
s
e
a
r
e
ba
s
e
d
on
m
a
t
h
e
m
a
t
i
c
a
l
for
m
ul
a
t
i
ons
.
U
s
ua
l
l
y
,
s
ys
t
e
m
s
m
a
k
e
i
n
a
c
c
e
p
t
a
b
i
l
i
t
y
,
a
n
d
i
ns
ur
m
oun
t
a
b
l
e
or
ot
h
e
r
i
s
s
ue
s
,
b
ut
s
o
ft
c
om
pu
t
i
n
g
re
pr
e
s
e
n
t
a
n
d
ha
nd
l
e
s
t
hi
s
ki
nd
of
pr
obl
e
m
s
e
a
s
i
l
y.
I
t
i
s
a
l
s
o
us
e
d
t
o
s
ol
ve
m
e
t
h
e
ur
i
s
t
i
c
s
a
s
w
e
l
l
a
s
n
a
t
u
re
-
i
ns
pi
r
e
d
prob
l
e
m
s
[22]
.
Int
e
r
ne
t
of
t
hi
ng
:
Cons
i
s
t
s
of
s
e
l
f
-
c
on
fi
gur
a
t
i
on
no
de
s
t
h
a
t
a
re
c
onn
e
c
t
e
d
w
i
t
h
dy
n
a
m
i
c
a
nd
w
i
t
h
g
l
oba
l
ne
t
w
ork
i
nfra
s
t
ruc
t
ur
e
.
It
i
s
c
o
m
pr
i
s
e
d
of
s
m
a
l
l
t
hi
ngs
w
i
t
h
l
i
m
i
t
e
d
s
t
ora
ge
a
n
d
pro
c
e
s
s
i
ng
s
ys
t
e
m
.
In
t
e
r
ne
t
of
a
n
i
t
e
m
re
fe
rs
t
o
a
b
roa
d
vi
s
i
on
.
T
hi
n
gs
a
re
s
u
c
h
w
a
ys
t
ha
t
e
ve
ryd
a
y
ob
j
e
c
t
s
a
n
d
pl
a
c
e
e
n
vi
ron
m
e
nt
s
a
re
i
nt
e
rc
o
nne
c
t
e
d
w
i
t
h
t
h
e
i
nt
e
rne
t
[2
3]
a
s
w
e
know
t
h
a
t
IoT
i
s
a
n
i
m
po
rt
a
nt
s
o
urc
e
of
bi
g
d
a
t
a
.
T
h
e
s
m
a
r
t
c
i
t
y
i
s
t
he
m
a
i
n
d
a
t
a
s
c
or
e
s
l
i
k
e
i
nd
us
t
ry
,
a
gr
i
c
u
l
t
ur
e
,
t
ra
f
fi
c
,
t
r
a
ns
port
,
m
e
d
i
c
a
l
,
pub
l
i
c
d
e
p
a
rt
m
e
n
t
a
nd
s
o
c
i
a
l
,
m
e
d
i
a
.
In
IoT
,
a
l
l
t
h
e
d
e
v
i
c
e
s
a
re
c
onne
c
t
e
d
,
a
nd
s
ys
t
e
m
a
r
c
hi
t
e
c
t
u
re
s
houl
d
s
up
port
Io
T
l
i
ke
a
br
i
dge
Evaluation Warning : The document was created with Spire.PDF for Python.
Com
pu
t
S
c
i
Inf
T
e
c
h
nol
IS
S
N
:
2722
-
3221
Cl
oud
c
om
p
ut
i
ng
ne
e
ds
t
o
e
x
pl
or
e
i
nt
o
s
k
y
c
om
pu
t
i
ng
(
A
r
i
f
U
l
l
ah)
297
be
t
w
e
e
n
t
he
ph
ys
i
c
a
l
a
nd
vi
rt
u
a
l
w
or
l
d.
T
h
e
de
s
i
gn
pro
c
e
s
s
of
Io
T
ne
e
ds
t
o
c
he
c
k
m
a
ny
f
a
c
t
ors
s
uc
h
a
s
c
om
m
un
i
c
a
t
i
on,
p
roc
e
s
s
a
nd
c
o
m
m
e
r
c
i
a
l
m
ode
l
s
,
a
nd
s
e
c
uri
t
y.
In
t
e
r
na
t
i
on
a
l
t
e
l
e
c
om
m
uni
c
a
t
i
on
uni
o
n
(IT
U
)
s
ugge
s
t
e
d
four
-
l
a
ye
r
c
on
c
e
pt
s
i
n
Io
T
.
T
h
e
s
e
a
re
t
he
a
pp
l
i
c
a
t
i
on
l
a
ye
r,
ne
t
w
ork
l
a
y
e
r,
pe
r
c
e
pt
i
on
l
a
y
e
r
a
n
d
m
i
dd
l
e
l
a
y
e
r
[24]
.
T
h
e
a
pp
l
i
c
a
t
i
on
l
a
y
e
r
i
s
c
o
ns
i
s
t
i
ng
of
a
va
ri
o
us
a
ppl
i
c
a
t
i
on
t
h
a
t
of
fe
rs
di
f
fe
r
e
nt
s
e
rvi
c
e
s
.
T
hi
s
i
s
t
he
m
os
t
upp
e
r
l
a
ye
r
a
nd
i
s
vi
s
i
bl
e
t
o
t
h
e
us
e
r
.
T
he
r
e
i
s
no
u
ni
v
e
rs
a
l
s
t
a
nda
r
d
rul
e
for
de
v
e
l
o
pi
ng
a
n
a
ppl
i
c
a
t
i
on
l
a
y
e
r
.
I
t
c
a
n
be
de
s
i
gne
d
du
e
t
o
i
t
s
s
e
rvi
c
e
.
A
p
pl
i
c
a
t
i
on
l
a
ye
r
pro
t
oc
ol
s
a
re
di
s
t
ri
bu
t
e
d
t
o
m
ul
t
i
p
l
e
us
e
rs
.
T
h
e
y
c
a
n
us
e
a
ny
i
nfor
m
a
t
i
on
w
i
t
h
t
he
he
l
p
of
t
he
s
e
pro
t
oc
o
l
s
[25]
.
T
h
e
n
e
t
w
ork
l
a
ye
r
prov
i
d
e
s
ne
t
w
ork
t
ra
ns
m
i
s
s
i
on
a
nd
i
nfor
m
a
t
i
on
s
e
c
ur
i
t
y
a
nd
de
l
i
v
e
rs
a
p
e
rv
a
s
i
ve
a
c
c
e
s
s
e
nv
i
ron
m
e
n
t
t
o
t
h
e
p
e
rc
e
p
t
i
on
l
a
y
e
r
t
h
a
t
prov
i
de
s
d
a
t
a
t
ra
ns
m
i
s
s
i
o
n
a
nd
s
t
or
a
g
e
a
w
a
r
e
ne
s
s
.
T
he
ne
t
w
ork
l
a
y
e
r
i
n
c
l
ud
e
s
m
ob
i
l
e
d
e
v
i
c
e
s
,
c
l
oud
c
om
p
ut
i
ng,
a
n
d
t
he
i
n
t
e
rn
e
t
.
T
h
e
p
e
rc
e
p
t
i
on
l
a
ye
r
i
s
i
nvol
v
e
d
i
n
t
he
c
ol
l
e
c
t
i
o
n
of
i
n
form
a
t
i
on
,
a
nd
i
t
’s
a
n
i
nt
e
r
c
onn
e
c
t
e
d
n
e
t
w
or
k
l
a
y
e
r
.
T
h
i
s
l
a
y
e
r
c
ons
i
s
t
s
of
a
l
l
s
e
ns
or
no
de
s
i
t
m
e
a
ns
a
l
l
s
e
ns
i
ng
t
e
c
hno
l
og
i
e
s
a
n
d
c
ont
r
ol
l
i
ng
d
a
t
a
a
c
qui
r
e
d
i
n
c
l
u
de
t
h
e
pe
rc
e
pt
i
on
l
a
ye
r
,
a
r
e
di
vi
d
e
d
i
n
t
o
s
ub
-
l
a
ye
r
[
26]
.
T
h
e
y
c
a
n
c
h
a
nge
a
c
c
ordi
ng
t
o
t
h
e
r
e
qu
i
re
m
e
n
t
a
nd
de
m
a
nd
a
nd
b
e
c
o
m
e
a
d
i
ffe
re
nt
l
a
ye
r,
a
n
d
t
he
s
e
l
a
y
e
rs
v
a
ry
a
c
c
or
di
ng
t
o
t
he
de
ve
l
op
m
e
n
t
a
nd
re
qui
r
e
m
e
n
t
.
Cl
oud
Com
pu
t
i
ng
:
T
hi
s
i
s
t
he
m
od
e
rn
a
nd
bus
y
t
e
c
hno
l
ogy
i
n
t
h
e
d
i
s
t
ri
but
e
d
c
om
put
i
ng
c
o
m
m
u
ni
t
y.
T
he
r
e
s
e
a
rc
h
e
r
s
be
l
i
e
ve
t
ha
t
i
t
c
ha
n
ge
s
t
h
e
i
nd
us
t
ry
a
s
a
re
v
a
l
ua
t
i
on
a
nd
i
s
t
h
e
ne
xt
-
g
e
n
e
ra
t
i
on
a
rc
h
i
t
e
c
t
ur
e
of
t
he
e
nt
e
rpri
s
e
.
C
l
oud
c
om
put
i
ng
m
o
ve
s
s
oft
w
a
re
a
nd
d
a
t
a
ba
s
e
t
o
a
c
e
n
t
ra
l
i
z
e
d
d
a
t
a
b
a
s
e
for
t
h
e
us
e
r
[
27]
.
T
h
e
ha
rdw
a
re
l
a
ye
r
i
s
re
s
po
ns
i
bl
e
for
m
a
na
g
i
ng
a
l
l
phys
i
c
a
l
r
e
s
o
urc
e
s
of
c
l
oud
c
om
p
ut
i
ng,
s
uc
h
a
s
phys
i
c
a
l
s
e
rvi
c
e
rs
,
rou
t
e
rs
,
s
w
i
t
c
h
e
s
,
pow
e
r,
c
oo
l
i
n
g
s
ys
t
e
m
,
a
nd
di
ff
e
re
nt
re
s
our
c
e
s
.
C
l
oud
c
o
m
pu
t
i
n
g
s
uppo
rt
s
e
l
a
s
t
i
c
s
e
rvi
c
e
f
or
t
he
us
e
r
t
o
m
a
x
i
m
i
z
e
t
he
re
s
ou
rc
e
s
t
h
a
t
i
nt
e
rne
t
s
e
rv
i
c
e
s
prov
i
de
rs
produ
c
e
.
D
u
e
t
o
t
he
s
e
c
ha
r
a
c
t
e
r
i
s
t
i
c
s
,
c
l
oud
c
om
put
i
ng
ha
s
be
c
o
m
e
t
h
e
hot
t
e
s
t
t
e
c
hnol
ogy
.
CC
c
ons
i
s
t
s
of
vi
r
t
u
a
l
i
z
a
t
i
o
n,
w
hi
c
h
i
s
i
nt
e
rc
o
nne
c
t
e
d.
It
c
ons
i
s
t
s
of
a
pa
r
a
l
l
e
l
a
nd
di
s
t
ri
bu
t
e
d
s
ys
t
e
m
,
w
h
i
c
h
c
a
n
be
dyna
m
i
c
a
l
l
y
pre
s
e
nt
e
d
a
nd
provi
d
e
t
he
c
o
m
put
i
ng
re
s
our
c
e
ba
s
e
d
on
s
om
e
s
e
r
vi
c
e
s
e
s
t
a
bl
i
s
he
d
be
t
w
e
e
n
c
us
t
o
m
e
r
a
nd
s
e
rv
i
c
e
prov
i
d
e
r
[28]
.
Bu
t
a
l
l
t
h
e
a
bo
ve
c
ha
r
a
c
t
e
r
i
s
t
i
c
s
,
CC
s
t
i
l
l
fa
c
i
ng
i
s
s
ue
s
t
h
a
t
a
re
m
e
n
t
i
o
ne
d
i
n
t
he
n
e
x
t
s
e
c
t
i
on
.
Cons
i
de
ra
b
l
e
b
e
ne
f
i
t
s
t
h
e
r
e
a
re
s
e
ri
ous
c
onc
e
rns
a
n
d
c
ha
l
l
e
ng
e
s
a
bou
t
t
h
i
s
n
e
w
t
e
c
hno
l
ogy
.
W
hi
c
h
a
r
e
m
e
n
t
i
on
e
d
in
T
a
bl
e
1
a
nd
F
i
gur
e
2.
F
i
gur
e
3
s
how
s
t
h
e
m
a
i
n
c
ha
l
l
e
ng
e
s
of
c
l
oud
c
om
p
ut
i
ng:
p
e
rfor
m
a
nc
e
s
,
m
a
n
a
gi
ng
c
os
t
,
l
a
c
k
of
re
s
our
c
e
,
c
o
m
pl
a
i
n
,
a
n
d
s
e
c
ur
i
t
y
.
F
i
g
ure
3
.
Is
s
u
e
in
c
l
o
ud
c
o
m
put
i
ng
4.
C
LO
U
D
C
O
M
P
U
TI
N
G
C
H
A
LLEN
G
ES
T
he
a
ppr
ova
l
ra
t
i
n
g
of
c
l
o
ud
c
om
pu
t
i
ng
as
an
e
m
e
rgi
ng
t
e
c
h
nol
ogy
ha
s
b
e
e
n
e
nh
a
n
c
e
d
s
i
gni
fi
c
a
n
t
l
y
.
T
he
s
e
da
ys
,
m
a
ny
c
l
o
uds
s
t
or
a
ge
a
nd
c
om
put
i
ng
pro
vi
d
e
rs
off
e
r
t
he
i
r
s
e
rv
i
c
e
s
re
g
a
rd
i
ng
I
a
a
S
,
P
a
a
S
,
a
nd
S
a
a
S
.
T
a
b
l
e
1
pre
s
e
nt
t
he
i
s
s
ue
s
of
c
l
oud
c
om
p
ut
i
ng.
O
n
e
of
t
h
i
s
m
a
i
n
i
s
s
ue
c
l
oud
n
e
e
d
to
be
fa
c
e
d
in
ne
a
r
fut
ur
e
is
b
i
g
d
a
t
a
i
s
s
ue
F
i
gur
e
3
p
re
s
e
nt
bi
g
d
a
t
a
i
s
s
ue
s
.
Evaluation Warning : The document was created with Spire.PDF for Python.
IS
S
N
:
2722
-
3221
Com
pu
t
S
c
i
Inf
T
e
c
h
nol
,
V
o
l
.
6
,
N
o
.
3
,
N
ov
e
m
be
r
20
25
:
294
-
306
298
T
a
b
l
e
1.
Is
s
ue
s
in
c
l
oud
c
om
p
ut
i
ng
Cl
o
u
d
c
o
m
p
u
t
i
n
g
Ch
a
l
l
e
n
g
e
s
Re
l
i
a
b
i
l
i
t
y
P
o
s
s
i
b
i
l
i
t
y
o
f
fa
i
l
u
re
i
n
s
t
a
n
d
p
e
ri
o
d
o
f
t
i
m
e
.
In
t
e
ro
p
e
ra
b
i
l
i
t
y
L
a
c
k
o
f
s
t
a
n
d
a
rd
s
fo
r
s
e
rv
i
c
e
p
o
rt
a
b
i
l
i
t
y
b
e
t
w
e
e
n
Cl
o
u
d
p
ro
v
i
d
e
rs
.
E
n
e
rg
y
s
a
v
i
n
g
D
e
fi
n
i
n
g
a
s
t
a
n
d
a
rd
m
e
t
ri
c
fo
r
e
ffe
c
t
i
v
e
p
o
w
e
r
u
s
a
g
e
a
n
d
a
n
e
ffi
c
i
e
n
t
s
t
a
n
d
a
rd
o
f
i
n
fra
s
t
ru
c
t
u
re
u
s
a
g
e
Re
s
i
l
i
e
n
c
y
T
h
e
a
b
i
l
i
t
y
o
f
t
h
e
s
y
s
t
e
m
t
o
p
ro
v
i
d
e
u
s
e
rs
w
i
t
h
s
t
a
n
d
a
rd
l
e
v
e
l
o
f
s
e
rv
i
c
e
s
w
h
i
l
e
e
x
p
e
ri
e
n
c
i
n
g
fa
u
l
t
s
a
n
d
c
h
a
l
l
e
n
g
e
s
i
n
t
h
e
s
y
s
t
e
m
Re
s
o
u
rc
e
m
o
n
i
t
o
ri
n
g
L
a
c
k
o
f
a
c
c
u
ra
t
e
m
o
n
i
t
o
ri
n
g
m
e
c
h
a
n
i
s
m
u
s
i
n
g
s
e
n
s
o
rs
t
o
c
o
l
l
e
c
t
t
h
e
d
a
t
a
fro
m
CP
U
l
o
a
d
,
a
n
d
m
e
m
o
ry
l
o
a
d
.
L
o
a
d
b
a
l
a
n
c
i
n
g
L
a
c
k
o
f
s
t
a
n
d
a
rd
w
a
y
o
f
l
o
a
d
m
o
n
i
t
o
ri
n
g
a
n
d
l
o
a
d
m
a
n
a
g
e
m
e
n
t
fo
r
d
i
ffe
re
n
t
Cl
o
u
d
a
p
p
l
i
c
a
t
i
o
n
s
[2
9
]
.
F
i
gure
4
s
how
s
t
h
e
grow
t
h
of
c
l
oud
c
om
p
ut
i
ng,
bi
g
da
t
a
a
nd
t
he
w
e
b
fro
m
20
09
to
2025
.
T
he
gra
ph
i
c
s
how
s
t
h
a
t
bi
g
d
a
t
a
a
n
d
w
e
b
s
e
r
vi
c
e
s
h
a
ve
i
nc
r
e
a
s
e
d
100%
in
e
ve
ry
fi
e
l
d
of
l
i
f
e
.
Ba
s
e
d
on
t
h
e
s
e
re
s
ul
t
s
,
now
it
is
t
i
m
e
to
m
ove
fr
om
t
he
c
l
oud
to
t
h
e
S
k
y
c
om
p
ut
i
ng
m
o
de
l
.
It
be
c
om
e
s
c
h
a
l
l
e
ng
i
ng
to
m
a
n
a
ge
t
he
s
ys
t
e
m
.
C
l
oud
d
i
s
c
a
rde
d
m
a
ny
of
i
t
s
d
ra
w
b
a
c
ks
,
b
e
c
om
i
ng
m
or
e
e
ff
i
c
i
e
n
t
a
nd
s
pre
a
d
i
ng
out
be
t
w
e
e
n
d
i
ff
e
re
n
t
t
e
c
h
nol
o
gi
e
s
.
Co
m
m
on
prob
l
e
m
s
c
o
nc
e
rn
e
d
w
i
t
h
c
l
oud
c
om
p
ut
i
ng
a
r
e
c
os
t
,
que
u
e
s
,
s
l
ow
de
ve
l
op
m
e
n
t
,
a
nd
l
i
m
i
t
e
d
c
a
pa
c
i
t
y
.
A
ft
e
r
t
he
e
v
a
l
u
a
t
i
on
a
nd
m
a
t
uri
ng
of
c
l
oud
c
om
put
i
ng
a
nd
c
l
ou
d
i
nt
e
gra
t
i
o
n
w
i
t
h
di
ff
e
r
e
nt
t
e
c
hno
l
ogi
e
s
or
v
i
c
e
ve
rs
a
,
t
he
re
s
ul
t
c
re
a
t
e
s
an
o
pport
uni
t
y
to
e
m
e
rg
e
a
ne
w
c
l
ou
d
m
ode
l
for
di
f
fe
r
e
nt
a
ppl
i
c
a
t
i
on
re
s
e
a
r
c
he
rs
to
p
re
s
e
nt
it
as
a
c
l
ou
d
-
to
-
c
l
oud
s
e
rv
i
c
e
or
s
k
y
c
om
put
i
ng
.
T
hi
s
ki
nd
of
m
od
e
l
p
rovi
d
e
s
hi
gh
-
p
e
rfor
m
a
n
c
e
c
o
m
put
i
ng
,
a
c
o
m
pl
e
x
pro
bl
e
m
-
s
o
l
vi
n
g
c
l
a
s
s
t
h
a
t
a
ri
s
e
s
as
ne
w
bus
i
ne
s
s
c
ons
u
m
e
rs
.
T
h
e
e
xp
e
c
t
a
t
i
on
is
t
a
ki
ng
a
dv
a
nt
a
g
e
of
t
h
e
c
l
o
ud
pre
m
i
s
e
s
[30
]
.
T
he
ne
w
m
ode
l
provi
d
e
s
di
ff
e
re
nt
s
e
rv
i
c
e
s
l
i
ke
i
nfra
s
t
ruc
t
ur
e
,
r
e
s
ourc
e
pl
a
t
form
,
a
nd
t
h
e
ne
w
m
od
e
l
s
ky
Co
m
pu
t
i
ng
w
i
l
l
prove
pow
e
rful
b
a
c
k
e
nd.
F
i
g
ure
4
.
C
l
oud
c
om
p
a
ri
s
o
n
w
i
t
h
ot
h
e
r
t
e
c
hn
ol
og
y
5.
S
K
Y
C
O
M
P
U
TI
N
G
M
O
D
EL
A
c
c
ord
i
ng
to
t
h
e
a
ut
h
or
[
31],
[32]
,
t
h
e
n
e
w
pr
opos
e
d
m
ode
l
s
ky
c
om
p
ut
i
ng
t
he
a
p
pl
i
c
a
t
i
o
n
i
nt
e
gra
t
i
o
n
of
di
ff
e
r
e
nt
s
e
ve
r
a
l
a
l
ong
w
i
t
h
t
he
i
nt
e
gr
a
t
i
on
of
publ
i
c
a
n
d
pri
v
a
t
e
c
l
oud
r
e
s
ourc
e
s
.
It
prov
i
de
s
a
good
re
s
ul
t
a
nd
d
e
fi
ne
s
a
us
e
r
r
ol
e
s
t
ra
t
e
gy
b
a
s
e
d
on
a
fe
d
e
r
a
t
e
d
a
ut
he
n
t
i
c
a
t
i
on
s
ys
t
e
m
.
T
h
e
prop
os
e
d
m
ode
l
a
l
s
o
provi
de
s
ba
l
a
n
c
e
d
l
ow
c
os
t
a
nd
pe
rfor
m
a
n
c
e
.
S
k
y
c
om
put
i
n
g
is
a
ne
w
i
n
c
i
pi
e
nt
c
o
m
pu
t
i
ng
e
xe
m
pl
a
ry
w
he
re
a
s
s
e
t
s
fro
m
m
ul
t
i
p
l
e
c
l
ouds
a
m
a
l
g
a
m
a
t
e
i
nt
o
.
O
n
e
a
n
d
prov
i
de
l
e
ve
r
a
ge
to
c
r
e
a
t
e
s
c
a
l
e
a
n
d
di
s
t
ri
b
ut
e
d
i
nfra
s
t
ruc
t
ur
e
,
a
n
d
F
i
gure
5
s
tr
u
c
t
u
re
of
S
ky
m
od
e
l
[33]
.
It
a
l
l
ow
s
a
us
e
r
to
m
e
c
h
a
ni
s
m
a
l
l
t
h
e
pos
s
e
s
s
i
ons
on
t
h
e
i
r
o
w
n
[35]
.
It
is
an
a
dv
a
n
c
e
d
de
v
e
l
opm
e
nt
in
t
h
e
c
o
m
pu
t
i
n
g
w
orl
d
.
H
e
re
m
ul
t
i
p
l
e
c
l
o
uds
a
r
e
i
n
t
e
gra
t
e
d
to
s
e
rve
t
h
e
bus
i
n
e
s
s
proc
e
s
s
in
o
ne
p
l
a
c
e
.
S
ky
c
o
m
put
i
ng
is
a
c
o
m
pu
t
i
ng
a
r
e
a
w
he
r
e
r
e
s
our
c
e
s
a
re
l
e
ve
ra
g
e
d
to
c
ra
ft
l
a
rg
e
-
s
c
a
l
e
d
i
s
s
e
m
i
na
t
e
d
vi
rt
u
a
l
c
l
us
t
e
rs
.
It
is
c
ha
l
l
e
ng
i
ng
d
ue
to
t
h
e
di
ffe
r
e
n
c
e
be
t
w
e
e
n
di
ff
e
r
e
nt
prov
i
de
rs
[36]
.
T
hi
s
c
ons
i
s
t
s
of
a
s
pe
c
i
a
l
l
a
y
e
r
t
ha
t
is
us
e
d
f
or
e
-
c
o
m
m
e
rc
e
.
It
s
s
e
c
uri
t
y
is
e
xc
e
p
t
i
o
na
l
be
c
a
us
e
it
us
e
s
a
s
p
e
c
i
a
l
m
e
t
hod
for
Evaluation Warning : The document was created with Spire.PDF for Python.
Com
pu
t
S
c
i
Inf
T
e
c
h
nol
IS
S
N
:
2722
-
3221
Cl
oud
c
om
p
ut
i
ng
ne
e
ds
t
o
e
x
pl
or
e
i
nt
o
s
k
y
c
om
pu
t
i
ng
(
A
r
i
f
U
l
l
ah)
299
ve
ri
f
i
c
a
t
i
on
[3
7]
.
It
c
om
bi
n
e
s
m
a
ny
c
l
o
uds
i
n
t
o
it
a
nd
m
a
ke
s
a
g
re
a
t
e
r
nu
m
be
r
of
r
e
s
our
c
e
s
to
prov
i
d
e
a
s
pe
c
i
a
l
n
um
b
e
r
of
d
i
s
t
ri
but
e
d
i
nf
ra
s
t
r
uc
t
ure
s
[38
]
.
W
he
n
d
i
ffe
r
e
nt
c
l
o
ud
c
o
m
pu
t
i
ng
m
e
rge
s
,
t
h
e
re
w
i
l
l
be
probl
e
m
s
re
l
a
t
e
d
t
o
d
i
ffe
r
e
n
t
r
e
s
our
c
e
s
a
nd
m
a
n
a
ge
m
e
nt
l
a
t
e
nc
y.
F
i
g
ure
5.
S
t
ruc
t
ure
of
S
ky
m
o
de
l
[3
4]
To
ove
r
c
o
m
e
t
hi
s
ki
nd
of
p
robl
e
m
,
t
h
e
r
e
m
us
t
be
a
s
t
ru
c
t
u
re
c
a
pa
b
l
e
of
r
e
c
e
i
v
i
ng
i
ns
t
ruc
t
i
o
n
a
nd
proc
e
s
s
re
s
u
l
t
s
fro
m
d
i
ff
e
re
n
t
c
l
oud
s
ys
t
e
m
s
.
As
we
kn
ow
t
h
a
t
e
a
c
h
c
l
ou
d
c
om
put
i
ng
ha
s
i
t
s
a
ppl
i
c
a
t
i
on
progra
m
m
i
ng
i
n
t
e
rf
a
c
e
(
API
)
t
ha
t
m
a
k
e
s
i
nt
e
ra
c
t
s
w
i
t
h
a
l
l
r
e
s
ourc
e
s
.
W
i
t
h
t
h
e
he
l
p
of
t
h
e
m
i
ddl
e
w
a
r
e
l
a
y
e
r
,
it
c
ont
ro
l
s
a
l
l
t
he
a
c
t
i
v
i
t
i
e
s
c
onc
e
rn
e
d
w
i
t
h
m
a
n
a
ge
m
e
nt
us
i
n
g
t
he
c
o
m
m
a
nd
.
F
i
gur
e
6
s
how
s
t
he
s
t
ruc
t
ur
e
of
S
ky
c
o
m
put
i
ng
.
S
om
e
of
t
h
e
m
a
i
n
e
l
e
m
e
n
t
s
of
S
ky
c
o
m
pu
t
i
ng
s
t
ru
c
t
ur
e
a
re
m
a
na
g
e
m
e
nt
,
a
c
c
oun
t
i
ng
,
b
i
l
l
i
ng
a
nd
m
oni
t
or
i
ng.
T
h
e
y
w
i
l
l
be
i
n
c
l
ud
e
d
in
t
he
f
i
rs
t
l
a
y
e
r
,
t
h
e
s
e
c
on
d
m
a
na
ge
m
e
n
t
l
a
y
e
r,
a
nd
t
h
e
t
h
i
rd
w
i
l
l
be
t
he
m
i
ddl
e
w
a
re
l
a
ye
r
[39
]
.
M
oni
t
or
i
ng
s
ys
t
e
m
:
t
hi
s
i
s
a
n
i
m
port
a
nt
p
a
rt
o
f
a
S
ky
c
o
m
put
i
n
g
m
a
na
g
e
m
e
nt
s
ys
t
e
m
.
In
a
c
l
ou
d
s
ys
t
e
m
,
bot
h
pr
i
va
t
e
a
nd
publ
i
c
c
os
t
m
on
e
y
.
I
n
pu
bl
i
c
s
u
i
t
e
c
os
t
bot
h
us
e
r
s
e
rvi
c
e
s
a
m
ul
t
i
pl
yi
ng
w
i
t
h
ha
rdw
a
re
prof
i
l
e
c
os
t
.
In
s
ky
c
o
m
pu
t
i
n
g,
a
r
c
hi
t
e
c
t
u
re
be
c
o
m
e
s
c
om
p
l
e
x
by
m
ul
t
i
p
l
yi
ng
h
a
rdw
a
re
c
os
t
t
o
us
e
r
re
s
ourc
e
be
c
a
us
e
t
h
e
r
e
a
r
e
us
e
d
m
a
ny
c
l
ou
ds
s
ys
t
e
m
t
og
e
t
h
e
r.
S
ky
c
om
put
i
ng
us
e
d
a
hybr
i
d
s
ys
t
e
m
,
i
t
c
ont
a
i
ns
publ
i
c
a
nd
pri
v
a
t
e
bo
t
h
b
i
l
l
i
ng
s
ys
t
e
m
a
t
a
t
i
m
e
a
nd
i
t
’s
a
l
s
o
us
e
d
a
h
e
a
l
t
hy
m
on
i
t
o
ri
ng
s
ys
t
e
m
[4
0]
.
M
i
ddl
e
w
a
r
e
:
t
h
i
s
is
an
e
s
s
e
nt
i
a
l
a
nd
fu
l
l
us
e
r
pa
r
t
of
c
ha
i
n
v
a
l
u
e
.
It
prov
i
de
s
an
a
bs
t
ra
c
t
i
on
to
d
e
ve
l
op
an
a
ppl
i
c
a
t
i
on
w
i
t
hou
t
a
ffe
c
t
i
ng
t
he
e
x
pl
i
c
i
t
of
c
l
oud
v
e
ndo
rs
.
But
in
s
ky
c
o
m
put
i
ng
,
m
i
dd
l
e
w
a
re
re
l
i
e
s
on
t
he
l
ow
e
r
l
a
y
e
r
a
nd
re
s
ou
rc
e
i
n
t
e
rf
a
c
e
to
be
s
t
a
bl
e
a
nd
de
pe
nda
bl
e
.
A
l
l
t
he
s
e
re
s
ou
rc
e
s
a
re
c
on
t
rol
l
e
d
a
nd
m
a
n
a
ge
d
by
t
he
m
i
ddl
e
w
a
r
e
l
a
y
e
r
.
E
nd
-
us
e
r
d
i
dn’
t
kn
ow
a
bout
t
h
e
a
c
t
i
vi
t
y
us
e
d
a
nd
fro
m
w
hi
c
h
l
oc
a
t
i
on
t
he
y
w
e
r
e
us
e
d
[4
1]
.
T
h
e
m
a
i
n
c
ha
l
l
e
ng
e
is
how
we
c
on
t
rol
t
h
e
r
e
s
our
c
e
l
i
k
e
p
ubl
i
c
-
p
ri
v
a
t
e
a
nd
i
nt
e
rop
e
ra
t
i
ng
s
ys
t
e
m
of
a
l
l
c
l
ou
d
m
e
r
ge
s
t
og
e
t
h
e
r.
L
i
k
e
t
hi
s
probl
e
m
a
n
d
o
t
he
rs
m
i
ddl
e
w
a
re
l
a
ye
r
a
r
e
us
e
d
to
s
ol
ve
t
h
e
p
robl
e
m
s
.
It
c
on
t
ro
l
s
a
l
l
t
h
e
s
e
l
a
pi
s
a
n
d
us
e
s
a
s
p
e
c
i
fi
c
c
o
m
m
a
nd
c
ont
ro
l
t
h
e
s
e
c
l
oud
provi
de
rs
as
l
ong
as
t
h
e
y
a
re
t
he
r
e
.
T
h
e
re
w
i
l
l
be
a
pa
r
t
of
t
he
m
i
ddl
e
l
a
y
e
r
know
n
as
HP,
w
hi
c
h
is
r
e
s
pons
e
-
a
b
l
e
f
or
s
c
he
du
l
i
n
g
a
nd
m
on
i
t
o
ri
ng
pur
pos
e
s
in
s
ky
c
o
m
put
i
ng
[42]
.
Evaluation Warning : The document was created with Spire.PDF for Python.
IS
S
N
:
2722
-
3221
Com
pu
t
S
c
i
Inf
T
e
c
h
nol
,
V
o
l
.
6
,
N
o
.
3
,
N
ov
e
m
be
r
20
25
:
294
-
306
300
D
i
ffe
r
e
nt
l
a
y
e
rs
a
r
e
us
e
d
in
s
ky
c
o
m
put
i
ng
.
T
h
e
upp
e
r
l
a
y
e
r
of
s
ky
c
om
p
ut
i
ng
is
i
nt
e
gra
t
e
d
w
i
t
h
groundw
ork
as
an
a
m
e
ni
t
y
a
nd
t
h
e
n
e
xt
l
a
y
e
r
of
s
of
t
w
a
r
e
as
a
p
a
c
ka
g
e
.
C
om
p
ut
i
ng
is
i
nt
e
gra
t
i
ng
w
i
t
h
i
nfra
s
t
ruc
t
ur
e
as
a
s
e
r
vi
c
e
a
n
d
t
h
e
ne
x
t
l
a
ye
r
of
s
of
t
w
a
r
e
as
a
s
e
r
vi
c
e
.
D
ue
to
t
he
r
e
p
a
i
d
grow
t
h
of
c
l
oud
c
om
p
ut
i
ng
in
t
h
e
m
a
rk
e
t
,
t
h
e
c
l
oud
p
rovi
d
e
s
i
t
s
ow
n
API
for
a
us
e
r
t
h
a
t
it
can
us
e
a
nyw
he
r
e
a
nd
a
ny
pl
a
c
e
[
43]
.
It
m
e
a
ns
t
ha
t
w
orks
a
re
pe
r
form
e
d
i
ndi
vi
du
a
l
.
It
a
l
s
o
prov
i
d
e
s
an
ope
n
s
l
ot
of
op
port
uni
t
y
for
t
he
i
nt
e
gr
i
t
y
of
c
l
oud
m
a
na
ge
m
e
n
t
a
nd
t
he
de
v
e
l
o
pm
e
nt
of
t
h
e
di
ffe
r
e
nt
s
e
r
i
a
l
c
l
ouds
.
S
e
c
uri
t
y
:
T
h
i
s
is
m
os
t
i
m
por
t
a
n
t
be
c
a
us
e
of
t
h
e
prov
i
de
r'
s
s
i
ngl
e
de
ve
l
o
pe
r
de
s
i
gn
a
pp
l
i
c
a
t
i
o
n
a
nd
pro
vi
d
e
r
s
e
c
uri
t
y
c
ont
e
xt
ua
l
i
z
a
t
i
on
m
e
a
s
ure
.
W
he
n
a
us
e
r
w
a
n
t
s
to
us
e
t
h
e
r
e
s
ourc
e
s
,
t
he
s
e
rvi
c
e
p
rovi
de
r
t
urns
t
h
e
s
e
r
vi
c
e
s
c
ont
r
ol
ov
e
r
.
T
h
i
s
fun
c
t
i
on
can
us
e
w
i
t
h
t
he
h
e
l
p
of
vi
rt
u
a
l
i
z
a
t
i
on
[
44]
.
F
i
gur
e
7
pr
e
s
e
n
t
t
he
s
e
c
ur
i
t
y
of
t
h
e
S
ky
m
od
e
l
s
ys
t
e
m
.
D
i
ffe
r
e
nt
c
l
ouds
w
i
t
h
a
c
e
r
t
a
i
n
e
nvi
r
onm
e
nt
u
nde
r
t
he
pri
n
c
i
pl
e
of
t
r
us
t
t
h
e
y
c
onf
i
gur
e
for
re
m
o
t
e
r
e
s
ourc
e
s
.
T
he
s
e
t
up
m
us
t
r
e
l
a
t
e
to
t
rus
t
.
If
not
,
t
he
n
not
be
c
onf
i
gur
e
d.
S
o
,
we
ne
e
d
a
t
rus
t
i
ng
re
l
a
t
i
ons
hi
p
b
e
t
w
e
e
n
t
h
e
m
.
D
yna
m
i
c
vi
r
t
ua
l
m
a
c
hi
ne
or
vi
r
t
u
a
l
t
rus
t
n
e
e
d
for
t
he
t
rus
t
r
e
l
a
t
i
ons
hi
p
[4
5]
.
F
i
g
ure
6.
S
e
c
ur
i
t
y
s
ys
t
e
m
of
s
ky
m
od
e
l
F
i
g
ure
7.
C
onne
c
t
v
i
t
y
s
ys
t
e
m
of
s
ky
m
od
e
l
M
a
ki
ng
t
rus
t
r
e
l
a
t
i
o
ns
hi
ps
i
s
ve
ry
d
i
ffi
c
ul
t
fo
r
us
e
rs
a
nd
pr
ovi
de
rs
.
I
t
i
s
n
’t
e
a
s
y
t
o
a
c
c
e
s
s
t
he
A
P
I
w
i
t
hou
t
t
he
pr
i
vi
l
e
g
e
a
nd
s
e
c
uri
t
y
t
o
c
on
fi
gur
e
a
ne
t
w
ork
[45]
.
Conn
e
c
t
i
v
i
t
y:
In
t
he
c
l
oud
,
re
s
our
c
e
s
a
r
e
i
nde
p
e
nd
e
nt
l
y
do
m
a
i
n
c
ons
t
ra
i
nt
s
l
i
k
e
pa
c
k
e
t
fi
l
t
e
ri
ng
,
ne
t
w
ork
a
ddr
e
s
s
,
a
nd
t
r
a
ns
l
a
t
i
on
.
T
o
ove
rc
o
m
e
t
hi
s
ki
nd
o
f
i
s
s
u
e
i
n
s
ky
c
o
m
put
i
ng
,
r
e
s
e
a
rc
h
e
rs
a
re
de
s
i
gni
n
g
a
nd
m
o
di
fy
i
ng
m
a
ny
n
e
t
w
o
rks
ov
e
rl
a
y
t
e
c
hni
que
s
for
c
o
nne
c
t
i
vi
t
y,
for
e
x
a
m
p
l
e
,
N
A
T
-
a
w
a
re
ne
t
w
ork
l
i
bra
r
i
e
s
a
nd
A
P
Is
,
v
i
rt
u
a
l
pri
va
t
e
ne
t
w
orks
(V
P
N
s
),
a
nd
pe
e
r
-
to
-
p
e
e
r
(P
2P
)
s
ys
t
e
m
s
[4
6]
.
P
e
rfor
m
a
n
c
e
:
ove
r
l
a
y
n
e
t
w
ork
e
ffe
c
t
t
he
p
e
rfor
m
a
nc
e
of
a
n
e
t
w
ork
.
Evaluation Warning : The document was created with Spire.PDF for Python.
Com
pu
t
S
c
i
Inf
T
e
c
h
nol
IS
S
N
:
2722
-
3221
Cl
oud
c
om
p
ut
i
ng
ne
e
ds
t
o
e
x
pl
or
e
i
nt
o
s
k
y
c
om
pu
t
i
ng
(
A
r
i
f
U
l
l
ah)
301
Im
prov
i
ng
t
he
ne
t
w
ork'
s
p
e
rfor
m
a
nc
e
m
us
t
a
v
oi
d
o
ve
r
l
a
y
n
e
t
w
orks
,
bu
t
i
t
i
s
c
h
a
l
l
e
n
gi
ng
t
o
do
[47]
.
S
e
rv
i
c
e
l
e
v
e
l
:
s
ky
c
om
p
ut
i
ng
n
e
e
d
s
t
o
pro
vi
d
e
s
e
rv
i
c
e
s
und
e
r
a
he
t
e
rog
e
ne
ous
e
n
vi
ron
m
e
nt
,
s
uc
h
a
s
d
i
ff
e
re
n
t
re
s
ourc
e
s
.
T
o
c
onn
e
c
t
di
ff
e
re
nt
re
s
o
urc
e
s
fr
om
di
ff
e
re
nt
l
oc
a
t
i
ons
a
nd
i
m
prov
e
t
he
i
r
pe
rf
orm
a
n
c
e
i
n
S
CC
de
ve
l
op
e
d
vi
rt
u
a
l
n
e
t
w
o
rk
(V
i
N
e
)
n
e
t
w
ork
i
ng
o
ve
r
l
a
y
.
I
t
c
ont
a
i
ns
o
t
h
e
r
e
n
ds
t
o
e
nd
c
onn
e
c
t
i
v
i
t
y
a
m
ong
di
ffe
r
e
n
t
nod
e
s
a
re
r
e
s
our
c
e
s
t
ha
t
a
r
e
pri
v
a
t
e
a
l
s
o.
I
t
c
o
nfi
g
ure
s
dyn
a
m
i
c
a
l
l
y
a
nd
s
e
c
ur
i
t
y
a
s
w
e
l
l
.
T
h
e
da
t
a
ra
t
e
a
nd
m
e
m
ory
a
r
e
m
ore
s
i
gn
i
fi
c
a
n
t
t
ha
n
ot
he
rs
.
S
om
e
o
f
t
he
m
a
i
n
a
dv
a
nt
a
g
e
s
of
V
i
N
e
A
r
e
V
i
N
e
-
e
na
b
l
e
d
provi
d
e
rs
,
e
nd
-
us
e
r
c
l
us
t
e
rs
,
i
s
ol
a
t
e
d
V
M
s
,
d
yn
a
m
i
c
c
onfi
g
ura
t
i
on
a
nd
t
rus
t
[4
8]
.
V
i
N
e
i
s
a
v
i
rt
u
a
l
ne
t
w
ork
t
ha
t
off
e
rs
e
nd
-
to
-
e
nd
V
i
N
e
t
ha
t
c
a
n
b
e
e
s
t
a
bl
i
s
he
d
a
t
di
ff
e
r
e
nt
l
e
ve
l
s
l
i
ke
t
he
s
a
m
e
d
e
vi
c
e
,
a
di
ff
e
re
nt
d
e
vi
c
e
,
a
nd
a
d
i
ff
e
re
n
t
ne
t
w
ork
.
It
h
a
s
a
dy
na
m
i
c
c
on
f
i
gur
a
t
i
on
m
a
n
a
ge
m
e
nt
s
ys
t
e
m
[
49]
.
F
i
gur
e
7
s
how
s
t
he
e
s
t
a
b
l
i
s
h
m
e
n
t
of
t
h
e
S
k
y
m
od
e
l
.
I
t
c
a
n
be
l
a
be
l
e
d
a
s
a
n
org
a
ni
z
a
t
i
on
up
-
l
a
y
e
r
of
c
l
o
uds
,
s
ub
m
i
s
s
i
on
v
a
ri
a
bl
e
c
om
p
ut
i
ng
a
bi
l
i
t
y
a
nd
s
t
or
a
g
e
r
e
s
our
c
e
s
w
i
t
h
vi
bra
n
t
s
us
t
e
n
a
nc
e
t
o
r
e
a
l
-
t
i
m
e
s
t
r
a
i
ns
.
L
a
yi
ng
a
v
i
rt
u
a
l
s
i
t
e
ov
e
r
di
s
s
e
m
i
na
t
e
d
r
e
s
our
c
e
s
,
uni
t
i
ng
t
he
a
bi
l
i
t
y
t
o
t
rus
t
r
e
m
o
t
e
s
i
t
e
s
w
i
t
h
a
t
rus
t
e
d
n
e
t
w
ork
i
ng
s
i
t
ua
t
i
o
n
[50]
.
A
f
t
e
r
t
he
s
t
udy
of
d
i
ff
e
re
n
t
s
e
c
t
i
ons
of
t
he
S
k
y
c
o
m
pu
t
i
ng
m
od
e
l
,
w
e
l
ook
a
t
t
he
r
e
s
e
a
rc
h
pa
p
e
r
w
h
e
re
di
ff
e
re
nt
s
e
a
rc
h
pr
e
s
e
n
t
di
ff
e
re
nt
m
o
de
l
s
a
bout
s
ky
c
o
m
pu
t
i
ng
[51
]
.
6.
I
M
P
O
R
TA
N
T
R
ES
U
L
TS
In
t
hi
s
s
e
c
t
i
on
,
we
pre
s
e
nt
t
hos
e
p
a
pe
rs
in
w
hi
c
h
di
ff
e
r
e
nt
re
s
e
a
r
c
h
pre
s
e
nt
t
he
s
ky
c
om
p
ut
i
ng
m
ode
l
.
P
rov
i
de
i
nf
orm
a
t
i
on
a
bo
ut
t
h
e
s
ky
m
o
de
l
a
nd
its
di
ffe
r
e
n
t
s
e
c
t
i
ons
a
re
pr
e
s
e
n
t
in
T
a
b
l
e
2.
S
ky
c
om
p
ut
i
ng
i
s
a
n
e
w
c
o
m
pu
t
i
ng
m
od
e
l
l
e
v
e
ra
g
i
ng
r
e
s
ourc
e
s
o
f
m
ul
t
i
p
l
e
c
l
oud
p
rovi
de
rs
t
o
c
re
a
t
e
a
l
a
rg
e
-
s
c
a
l
e
s
c
a
t
t
e
r
e
d
i
nfr
a
s
t
ru
c
t
u
re
.
T
he
S
ky
is
r
e
s
e
a
rc
h
c
re
a
t
i
vi
t
y
c
a
p
a
b
l
e
of
m
a
k
i
ng
a
fra
m
e
w
ork
for
u
t
i
l
i
z
i
ng
d
i
ffe
r
e
n
t
CC'
s
as
s
e
rvi
c
e
s
a
c
r
os
s
m
a
ny
l
o
c
a
t
i
o
ns
as
a
S
ky
m
ode
l
[52]
.
F
i
gure
8
pr
e
s
e
nt
t
h
e
s
ke
y
c
o
m
pu
t
i
ng
m
od
e
l
a
nd
it
di
ff
e
re
nt
e
l
e
m
e
n
t
s
w
i
t
h
t
h
e
i
r
w
ork
i
ng
m
o
de
l
s
.
T
a
b
l
e
2
.
L
i
t
e
r
a
t
ur
e
s
u
m
m
a
ry
Y
e
a
r
M
o
d
e
l
S
u
m
m
a
ry
Re
f
2008
S
k
y
c
o
m
p
u
t
i
n
g
P
ro
v
i
d
e
i
n
fo
rm
a
t
i
o
n
a
b
o
u
t
t
h
e
n
e
w
m
o
d
e
[5
3
]
2009
S
k
y
c
o
m
p
u
t
i
n
g
T
h
e
b
a
s
i
c
p
a
p
e
r
w
h
e
re
a
u
t
h
o
r
p
re
s
e
n
t
i
n
fo
rm
a
t
i
o
n
a
b
o
u
t
s
k
y
m
o
d
e
l
[5
4
]
2010
Cl
o
u
d
a
n
d
s
k
y
P
re
s
e
n
t
i
n
fo
rm
a
t
i
o
n
a
b
o
u
t
c
l
o
u
d
a
n
d
n
e
x
t
g
e
n
e
ra
t
i
o
n
a
b
o
u
t
s
k
y
[5
5
]
2011
Cl
o
u
d
a
n
d
s
k
y
P
re
s
e
n
t
s
e
c
u
ri
t
y
i
n
fo
rm
a
t
i
o
n
i
n
b
o
t
h
m
o
d
e
l
[5
6
]
2014
Cl
o
u
d
a
n
d
s
k
y
In
fo
rm
a
t
i
o
n
a
b
o
u
t
c
l
o
u
d
a
n
d
p
re
s
e
n
t
fu
t
u
re
m
o
d
e
l
s
k
y
[5
7
]
2016
S
k
y
c
o
m
p
u
t
i
n
g
P
re
s
e
n
t
i
n
fo
rm
a
t
i
o
n
a
b
o
u
t
d
i
ffe
re
n
t
d
o
m
a
i
n
o
f
t
h
e
p
r
o
p
o
s
e
d
m
o
d
e
l
[5
8
]
2019
S
k
y
c
o
m
p
u
t
i
n
g
W
h
e
n
Cl
o
u
d
s
S
t
a
rt
S
o
c
i
a
l
i
z
i
n
g
T
h
e
S
k
y
M
o
d
e
l
[5
9
]
2022
Cl
o
u
d
a
n
d
s
k
y
P
re
s
e
n
t
c
l
o
u
d
m
o
d
e
l
a
n
d
i
t
fu
t
u
re
d
i
re
c
t
i
o
n
[6
0
]
2024
S
k
y
c
o
m
p
u
t
i
n
g
P
re
s
e
n
t
t
h
e
l
a
y
e
r
s
t
ru
c
t
u
re
o
f
n
e
w
m
o
d
e
l
[6
1
]
2025
S
k
y
c
o
m
p
u
t
i
n
g
T
h
e
a
u
t
h
o
r
p
re
s
e
n
t
n
e
u
ra
l
n
e
t
w
o
rk
fo
r
m
a
y
c
l
o
u
d
i
n
t
e
ra
c
t
i
o
n
i
n
t
o
s
k
y
[
62]
2025
S
k
y
c
o
m
p
u
t
i
n
g
A
u
t
h
o
r
p
re
s
e
n
t
e
m
e
rg
i
n
g
c
o
m
p
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t
i
n
g
a
rc
h
i
t
e
c
t
u
re
s
a
n
d
m
e
n
t
i
o
n
s
k
y
[6
3
]
2025
Cl
o
u
d
c
o
m
p
u
t
i
n
g
A
u
t
h
o
r
p
re
s
e
n
t
N
e
x
t
g
e
n
e
ra
t
i
o
n
c
l
o
u
d
c
o
m
p
u
t
i
n
g
[6
4
]
F
i
g
ure
8.
S
ky
m
ode
l
[
65]
Evaluation Warning : The document was created with Spire.PDF for Python.
IS
S
N
:
2722
-
3221
Com
pu
t
S
c
i
Inf
T
e
c
h
nol
,
V
o
l
.
6
,
N
o
.
3
,
N
ov
e
m
be
r
20
25
:
294
-
306
302
T
he
s
t
u
dy
of
re
l
a
t
e
d
w
orks
a
n
d
t
h
e
s
u
m
m
a
ri
z
a
t
i
on
of
pa
p
e
rs
s
how
t
ha
t
d
i
ff
e
re
n
t
re
s
e
a
r
c
he
rs
a
re
i
m
p
l
e
m
e
n
t
i
n
g
s
ky
c
o
m
pu
t
i
ng
a
s
a
m
ode
l
.
T
h
e
a
r
c
hi
t
e
c
t
u
re
t
h
e
y
j
o
i
n
a
n
d
c
o
m
bi
ne
d
i
ffe
re
n
t
c
l
oud
r
e
s
ourc
e
s
or
c
l
oud
a
s
a
c
l
ou
d
m
a
y
be
p
ri
v
a
t
e
or
pub
l
i
c
a
nd
m
e
rge
t
he
m
w
i
t
h
t
h
e
h
e
l
p
of
a
m
i
dd
l
e
w
a
re
c
ont
r
ol
l
e
r
.
T
h
i
s
m
i
dd
l
e
w
a
re
f
l
a
w
l
e
s
s
l
y
di
s
t
ri
bu
t
e
d
r
e
s
ourc
e
s
upon
t
h
e
ove
r
he
a
d
l
a
y
e
rs
’
r
e
qu
e
s
t
s
,
a
l
l
ow
i
ng
m
oni
t
ori
n
g
a
nd
c
l
e
ri
c
a
l
f
or
i
nd
i
c
t
i
ng
pu
rpos
e
s
[66]
.
S
e
c
ond
l
y,
t
he
r
e
s
e
a
rc
h
e
r
c
hos
e
fro
m
t
h
e
a
v
a
i
l
a
b
l
e
op
e
n
-
s
our
c
e
s
of
t
w
a
r
e
t
o
c
om
b
i
ne
pa
r
t
s
of
t
h
e
m
od
e
l
a
nd
m
a
ke
i
t
w
ork
one
by
o
ne
.
A
ft
e
r
m
a
ny
e
x
a
m
i
n
a
t
i
ons
a
nd
u
pda
t
e
s
,
s
om
e
i
m
pro
ve
m
e
n
t
s
w
e
r
e
m
a
d
e
t
o
e
nha
nc
e
t
h
e
s
ys
t
e
m
.
T
h
e
y
w
e
r
e
a
b
l
e
t
o
de
c
l
a
re
t
h
e
re
s
u
l
t
a
bo
ut
s
ky
c
o
m
pu
t
i
ng
.
S
om
e
of
t
h
e
m
a
i
n
r
e
s
ul
t
s
a
bou
t
t
hi
s
m
od
e
l
a
r
e
a
s
f
ol
l
ow
s
:
T
h
e
pro
pos
e
d
S
ky
m
ode
l
s
h
oul
d
op
e
n
ne
w
pos
s
i
bi
l
i
t
i
e
s
for
t
h
e
c
urr
e
nt
c
l
oud
c
o
m
pu
t
i
n
g
m
od
e
l
.
B
y
a
n
d
hug
e
,
t
h
e
e
x
t
a
n
t
bus
i
n
e
s
s
m
o
de
l
i
s
c
l
oud
-
us
e
r
.
T
hough
a
w
i
d
e
-
op
e
n
w
i
ndow
of
oppor
t
un
i
t
i
e
s
i
s
ou
t
,
c
l
ouds
i
n
t
e
r
m
i
n
gl
e
w
i
t
h
ot
h
e
r
c
l
o
uds
t
o
w
ork
t
oge
t
he
r
a
nd
s
y
ne
rg
i
z
e
[6
7]
.
Curre
nt
l
y,
t
h
e
bus
i
n
e
s
s
-
to
-
b
us
i
ne
s
s
(
B2B)
bus
i
n
e
s
s
-
m
od
e
l
t
h
a
t
e
xi
s
t
s
be
t
w
e
e
n
t
h
e
c
us
t
o
m
a
ry
e
-
bus
i
ne
s
s
e
s
.
T
hi
s
k
i
nd
of
t
e
a
m
w
ork
e
s
s
e
nt
i
a
l
l
y
i
nv
ol
v
e
s
v
a
l
i
d
a
t
i
ng
ri
gor
ous
b
us
i
n
e
s
s
s
t
r
a
t
e
gi
e
s
a
nd
a
g
re
e
m
e
nt
s
b
e
t
w
e
e
n
t
he
c
l
ou
ds
t
he
m
s
e
l
ve
s
a
nd
m
ore
d
e
c
i
s
i
v
e
l
y
b
e
t
w
e
e
n
t
he
S
ky
,
a
s
a
w
h
ol
e
,
a
nd
t
h
e
e
nd
-
us
e
rs
.
E
x
a
m
pl
e
s
of
t
h
i
s
k
i
nd
of
bus
i
n
e
s
s
a
re
s
ubc
o
nt
r
a
c
t
i
ng
a
nd
out
s
our
c
i
n
g,
a
nd
p
a
rt
ne
rs
h
i
p
[68]
.
7.
S
K
Y
M
O
D
E
L
C
H
A
LLEN
G
ES
T
h
e
a
dop
t
i
on
o
f
c
l
o
ud
c
om
pu
t
i
ng
i
s
a
l
r
e
a
dy
c
on
c
e
rn
e
d
w
i
t
h
d
i
ff
e
r
e
n
t
k
i
n
ds
of
c
ha
l
l
e
ng
e
s
a
nd
op
e
n
i
s
s
u
e
s
.
D
u
e
t
o
t
h
os
e
i
s
s
u
e
s
,
c
l
o
ud
p
rov
i
d
e
rs
l
i
k
e
A
m
a
z
o
n,
M
i
c
ros
of
t
a
nd
G
o
og
l
e
)
us
e
d
o
t
h
e
r
t
e
c
hno
l
o
gi
e
s
a
n
d
vi
s
i
ons
t
o
ov
e
r
c
o
m
e
t
h
e
s
e
i
s
s
u
e
s
.
W
h
e
n
t
h
e
y
a
d
op
t
t
h
i
s
ne
w
m
od
e
l
,
t
h
e
y
m
a
y
b
e
f
a
c
e
d
t
h
e
a
b
ov
e
i
s
s
ue
s
.
S
t
a
nd
a
r
di
z
a
t
i
o
n
i
s
a
l
s
o
a
n
i
s
s
u
e
i
n
t
h
e
s
k
y
m
od
e
l
b
e
c
a
us
e
o
f
d
i
ff
e
r
e
n
c
e
s
a
m
o
ng
d
i
ff
e
r
e
n
t
c
l
o
uds
a
nd
us
e
rs
.
T
h
i
s
pro
c
e
s
s
u
na
vo
i
d
a
b
l
y
d
e
m
a
nds
s
t
a
nd
a
r
di
z
i
n
g
t
h
e
n
e
c
e
s
s
a
ry
s
t
ora
g
e
s
ys
t
e
m
a
nd
pr
oc
e
s
s
i
n
g
s
ys
t
e
m
[6
9]
.
T
r
us
t
a
nd
p
ri
v
a
c
y
bo
t
h
a
re
t
h
e
m
a
i
n
i
s
s
u
e
s
i
n
t
h
e
s
k
y
c
o
m
p
ut
i
n
g
m
o
de
l
a
l
s
o
.
T
hi
s
i
s
du
e
t
o
c
on
c
e
r
n
of
c
l
o
ud
c
on
n
e
c
t
i
on
a
s
w
e
l
l
a
s
us
e
r
s
i
t
e
.
S
o
,
t
h
e
t
rus
t
a
nd
pr
i
v
a
c
y
a
r
e
m
o
re
f
oc
us
e
d
i
n
t
h
e
s
k
y
m
o
d
e
l
b
e
c
a
us
e
i
t
c
o
ns
i
s
t
s
of
di
ff
e
r
e
n
t
l
a
y
e
rs
a
nd
m
or
e
c
o
nn
e
c
t
i
o
n
s
e
c
t
i
o
ns
;
t
he
re
fo
re
,
n
e
e
d
m
o
re
s
e
c
ur
i
t
y
op
t
i
ons
[7
0]
.
S
e
r
vi
c
e
s
l
e
v
e
l
a
rr
a
n
g
e
m
e
n
t
(S
L
A
)
i
s
a
n
i
m
p
or
t
a
nt
i
s
s
u
e
w
a
s
i
n
c
l
oud
c
o
m
p
ut
i
ng
,
a
nd
i
t
w
i
l
l
b
e
t
he
i
s
s
u
e
i
n
s
ky
c
o
m
pu
t
i
ng
.
W
e
s
h
ou
l
d
r
e
m
e
m
be
r
t
h
a
t
p
re
di
c
t
i
ng
t
he
p
e
r
for
m
a
n
c
e
of
s
e
pa
ra
t
e
d
c
l
ou
d
s
e
r
vi
c
e
s
i
s
c
onv
ol
ut
e
d
e
no
ug
h
d
u
e
t
o
t
h
e
w
i
d
e
us
e
of
v
i
r
t
u
a
l
m
a
c
hi
ne
s
.
S
o
,
s
e
rv
i
c
e
s
l
e
ve
l
a
r
ra
ng
e
m
e
n
t
i
s
a
l
s
o
a
n
i
m
p
or
t
a
n
t
i
s
s
u
e
t
h
a
t
e
xi
t
i
n
t
h
e
S
k
y
c
o
m
p
ut
i
n
g
m
od
e
l
[
69]
.
D
e
s
i
gn
i
n
g
a
nd
i
m
p
l
e
m
e
nt
i
n
g
i
s
s
u
e
s
a
l
s
o
e
x
i
s
t
i
n
s
ky
c
om
pu
t
i
ng
fro
m
t
h
e
s
t
u
dy
of
re
l
a
t
e
d
w
o
rk
.
It
s
e
e
m
s
t
ha
t
d
i
ff
e
r
e
n
t
k
i
nds
o
f
i
s
s
u
e
s
e
xi
s
t
on
di
f
fe
re
nt
p
l
a
t
for
m
s
.
S
o
m
e
of
t
h
e
m
a
re
r
e
g
i
s
t
e
re
d
,
i
d
e
n
t
i
fy
i
ng
ot
he
rs
,
e
s
t
a
bl
i
s
h
i
n
g
s
o
c
i
a
l
c
onn
e
c
t
i
o
ns
,
a
n
d
e
ve
nt
u
a
l
l
y
i
n
t
e
r
a
c
t
i
ng
w
i
t
h
e
a
c
h
o
t
h
e
r
[71
]
.
8.
C
O
N
C
LU
S
I
O
N
S
ky
c
o
m
pu
t
i
n
g
is
an
a
dv
a
nc
e
d
c
o
m
pu
t
i
ng
s
ys
t
e
m
m
ode
l
w
he
re
m
ul
t
i
p
l
e
c
l
ouds
a
r
e
j
oi
n
e
d
t
og
e
t
he
r
for
s
ha
r
i
ng
t
he
pro
c
e
s
s
of
re
s
our
c
e
s
a
nd
m
a
na
g
e
m
e
n
t
in
one
p
l
a
c
e
.
E
s
t
a
bl
i
s
hi
ng
a
nd
m
a
i
n
t
a
i
ni
n
g
s
ky
c
om
p
ut
i
ng
is
v
e
ry
di
ff
i
c
ul
t
.
T
h
e
i
r
c
onne
c
t
i
vi
t
y
a
nd
a
rc
h
i
t
e
c
t
ur
e
a
re
a
l
s
o
a
c
t
u
a
l
de
m
a
n
di
ng
.
F
urt
h
e
rm
ore
,
in
s
ky
c
om
put
i
ng
,
s
c
a
l
a
b
i
l
i
t
y
a
n
d
d
i
s
t
r
i
but
i
on
of
c
om
p
ut
i
ng
a
n
d
t
he
i
r
m
e
a
s
ur
e
m
e
n
t
to
re
c
ov
e
r
from
f
a
ul
t
is
e
s
s
e
nt
i
a
l
for
a
p
pl
i
c
a
t
i
o
n
a
nd
go
od
pe
r
form
a
n
c
e
.
S
ky
c
o
m
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R
EF
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EN
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ES
[1
]
T
.
A
l
a
m
,
R
.
G
u
p
t
a
,
N
.
N
.
A
h
a
m
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d
,
A
.
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h
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.
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m
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t
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b
l
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s
h
a
g
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w
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:
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d
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p
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n
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e
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n
d
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0
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4
3
5
8
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2
4
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0
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0
9
2
-
4.
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]
A
.
M
o
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x
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,
a
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[3
]
S
.
Bra
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.
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[4
]
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.
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,
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.
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,
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.
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[5
]
C.
Ba
u
n
a
n
d
M
.
K
u
n
z
e
,
“
T
h
e
K
O
A
L
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c
l
o
u
d
m
a
n
a
g
e
m
e
n
t
s
e
rv
i
c
e
:
a
m
o
d
e
rn
a
p
p
ro
a
c
h
fo
r
c
l
o
u
d
i
n
fra
s
t
ru
c
t
u
re
m
a
n
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g
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m
e
n
t
,
”
P
r
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c
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d
i
n
g
s
o
f
t
h
e
1
s
t
In
t
e
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n
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t
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l
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k
s
h
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p
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d
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4
5
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1
9
6
7
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2
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9
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7
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2
3
.
[6
]
M
.
T
s
u
g
a
w
a
,
A
.
M
a
t
s
u
n
a
g
a
,
a
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d
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.
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s
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s
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l
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In
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[7
]
I.
Ba
rt
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l
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n
i
,
P
.
Ci
a
c
c
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a
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