<s>
A	O
view	B-Architecture
model	I-Architecture
or	O
viewpoints	O
framework	O
in	O
systems	O
engineering	O
,	O
software	B-General_Concept
engineering	I-General_Concept
,	O
and	O
enterprise	B-Architecture
engineering	I-Architecture
is	O
a	O
framework	O
which	O
defines	O
a	O
coherent	O
set	O
of	O
views	O
to	O
be	O
used	O
in	O
the	O
construction	O
of	O
a	O
system	B-Architecture
architecture	I-Architecture
,	O
software	B-Architecture
architecture	I-Architecture
,	O
or	O
enterprise	O
architecture	O
.	O
</s>
<s>
A	O
view	B-Algorithm
is	O
a	O
representation	O
of	O
the	O
whole	O
system	O
from	O
the	O
perspective	B-Architecture
of	O
a	O
related	O
set	O
of	O
concerns	O
.	O
</s>
<s>
Since	O
the	O
early	O
1990s	O
there	O
have	O
been	O
a	O
number	O
of	O
efforts	O
to	O
prescribe	O
approaches	O
for	O
describing	O
and	O
analyzing	O
system	B-Architecture
architectures	I-Architecture
.	O
</s>
<s>
They	O
are	O
sometimes	O
referred	O
to	O
as	O
architecture	B-Architecture
frameworks	I-Architecture
or	O
enterprise	B-Library
architecture	I-Library
frameworks	I-Library
,	O
but	O
are	O
usually	O
called	O
"	O
view	B-Architecture
models	I-Architecture
"	O
.	O
</s>
<s>
Usually	O
a	O
view	B-Algorithm
is	O
a	O
work	O
product	O
that	O
presents	O
specific	O
architecture	O
data	O
for	O
a	O
given	O
system	O
.	O
</s>
<s>
However	O
,	O
the	O
same	O
term	O
is	O
sometimes	O
used	O
to	O
refer	O
to	O
a	O
view	B-Algorithm
definition	O
,	O
including	O
the	O
particular	O
viewpoint	O
and	O
the	O
corresponding	O
guidance	O
that	O
defines	O
each	O
concrete	O
view	B-Algorithm
.	O
</s>
<s>
The	O
term	O
view	B-Architecture
model	I-Architecture
is	O
related	O
to	O
view	B-Algorithm
definitions	O
.	O
</s>
<s>
Most	O
complex	O
system	O
specifications	B-Application
are	O
so	O
extensive	O
that	O
no	O
single	O
individual	O
can	O
fully	O
comprehend	O
all	O
aspects	O
of	O
the	O
specifications	B-Application
.	O
</s>
<s>
Furthermore	O
,	O
we	O
all	O
have	O
different	O
interests	O
in	O
a	O
given	O
system	O
and	O
different	O
reasons	O
for	O
examining	O
the	O
system	O
's	O
specifications	B-Application
.	O
</s>
<s>
The	O
concept	O
of	O
viewpoints	O
framework	O
,	O
therefore	O
,	O
is	O
to	O
provide	O
separate	O
viewpoints	O
into	O
the	O
specification	B-Application
of	O
a	O
given	O
complex	O
system	O
in	O
order	O
to	O
facilitate	O
communication	O
with	O
the	O
stakeholders	O
.	O
</s>
<s>
Viewpoint	B-Architecture
modeling	I-Architecture
has	O
become	O
an	O
effective	O
approach	O
for	O
dealing	O
with	O
the	O
inherent	O
complexity	O
of	O
large	O
distributed	O
systems	O
.	O
</s>
<s>
Architecture	B-Architecture
description	I-Architecture
practices	O
,	O
as	O
described	O
in	O
IEEE	B-Architecture
Std	I-Architecture
1471-2000	I-Architecture
,	O
utilize	O
multiple	O
views	O
to	O
address	O
several	O
areas	O
of	O
concerns	O
,	O
each	O
one	O
focusing	O
on	O
a	O
specific	O
aspect	O
of	O
the	O
system	O
.	O
</s>
<s>
Examples	O
of	O
architecture	B-Architecture
frameworks	I-Architecture
using	O
multiple	O
views	O
include	O
Kruchten	O
's	O
"	B-Architecture
4+1	I-Architecture
"	I-Architecture
view	I-Architecture
model	I-Architecture
,	O
the	O
Zachman	B-Library
Framework	I-Library
,	O
TOGAF	O
,	O
DoDAF	O
,	O
and	O
RM-ODP	B-Operating_System
.	O
</s>
<s>
In	O
the	O
1970s	O
,	O
methods	O
began	O
to	O
appear	O
in	O
software	B-General_Concept
engineering	I-General_Concept
for	O
modeling	O
with	O
multiple	O
views	O
.	O
</s>
<s>
In	O
that	O
work	O
:	O
"	O
A	O
viewpoint	O
can	O
be	O
thought	O
of	O
as	O
a	O
combination	O
of	O
the	O
idea	O
of	O
an	O
“	O
actor	O
”	O
,	O
“	O
knowledge	O
source	O
”	O
,	O
“	O
role	O
”	O
or	O
“	O
agent	O
”	O
in	O
the	O
development	O
process	O
and	O
the	O
idea	O
of	O
a	O
“	O
view	B-Algorithm
”	O
or	O
“	O
perspective	B-Architecture
”	O
which	O
an	O
actor	O
maintains.	O
"	O
</s>
<s>
An	O
important	O
idea	O
in	O
this	O
paper	O
was	O
to	O
distinguish	O
"	O
a	O
representation	O
style	O
,	O
the	O
scheme	O
and	O
notation	O
by	O
which	O
the	O
viewpoint	O
expresses	O
what	O
it	O
can	O
see	O
"	O
and	O
"	O
a	O
specification	B-Application
,	O
the	O
statements	O
expressed	O
in	O
the	O
viewpoint	O
's	O
style	O
describing	O
particular	O
domains	O
"	O
.	O
</s>
<s>
Subsequent	O
work	O
,	O
such	O
as	O
IEEE	B-Architecture
1471	I-Architecture
,	O
preserved	O
this	O
distinction	O
by	O
utilizing	O
two	O
separate	O
terms	O
:	O
viewpoint	O
and	O
view	B-Algorithm
,	O
respectively	O
.	O
</s>
<s>
Since	O
the	O
early	O
1990s	O
there	O
have	O
been	O
a	O
number	O
of	O
efforts	O
to	O
codify	O
approaches	O
for	O
describing	O
and	O
analyzing	O
system	B-Architecture
architectures	I-Architecture
.	O
</s>
<s>
These	O
are	O
often	O
termed	O
architecture	B-Architecture
frameworks	I-Architecture
or	O
sometimes	O
viewpoint	O
sets	O
.	O
</s>
<s>
Among	O
these	O
,	O
the	O
IEEE	O
Recommended	O
Practice	O
for	O
Architectural	O
Description	O
of	O
Software-Intensive	O
Systems	O
(	O
IEEE	B-Architecture
Std	I-Architecture
1471-2000	I-Architecture
)	O
established	O
useful	O
definitions	O
of	O
view	B-Algorithm
,	O
viewpoint	O
,	O
stakeholder	O
and	O
concern	O
and	O
guidelines	O
for	O
documenting	O
a	O
system	B-Architecture
architecture	I-Architecture
through	O
the	O
use	O
of	O
multiple	O
views	O
by	O
applying	O
viewpoints	O
to	O
address	O
stakeholder	O
concerns	O
.	O
</s>
<s>
IEEE	B-Architecture
1471	I-Architecture
(	O
now	O
ISO/IEC/IEEE	O
42010:2011	O
,	O
Systems	O
and	O
software	B-General_Concept
engineering	I-General_Concept
—	O
Architecture	B-Architecture
description	I-Architecture
)	O
prescribes	O
the	O
contents	O
of	O
architecture	O
descriptions	O
and	O
describes	O
their	O
creation	O
and	O
use	O
under	O
a	O
number	O
of	O
scenarios	O
,	O
including	O
precedented	O
and	O
unprecedented	O
design	O
,	O
evolutionary	O
design	O
,	O
and	O
capture	O
of	O
design	O
of	O
existing	O
systems	O
.	O
</s>
<s>
In	O
all	O
of	O
these	O
scenarios	O
the	O
overall	O
process	O
is	O
the	O
same	O
:	O
identify	O
stakeholders	O
,	O
elicit	O
concerns	O
,	O
identify	O
a	O
set	O
of	O
viewpoints	O
to	O
be	O
used	O
,	O
and	O
then	O
apply	O
these	O
viewpoint	O
specifications	B-Application
to	O
develop	O
the	O
set	O
of	O
views	O
relevant	O
to	O
the	O
system	O
of	O
interest	O
.	O
</s>
<s>
In	O
1996	O
the	O
ISO	O
Reference	B-Operating_System
Model	I-Operating_System
for	I-Operating_System
Open	I-Operating_System
Distributed	I-Operating_System
Processing	I-Operating_System
(	O
RM-ODP	B-Operating_System
)	O
was	O
published	O
to	O
provide	O
a	O
useful	O
framework	O
for	O
describing	O
the	O
architecture	O
and	O
design	O
of	O
large-scale	O
distributed	O
systems	O
.	O
</s>
<s>
A	O
view	B-Algorithm
of	O
a	O
system	O
is	O
a	O
representation	O
of	O
the	O
system	O
from	O
the	O
perspective	B-Architecture
of	O
a	O
viewpoint	O
.	O
</s>
<s>
This	O
viewpoint	O
on	O
a	O
system	O
involves	O
a	O
perspective	B-Architecture
focusing	O
on	O
specific	O
concerns	O
regarding	O
the	O
system	O
,	O
which	O
suppresses	O
details	O
to	O
provide	O
a	O
simplified	O
model	O
having	O
only	O
those	O
elements	O
related	O
to	O
the	O
concerns	O
of	O
the	O
viewpoint	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
security	O
viewpoint	O
focuses	O
on	O
security	O
concerns	O
and	O
a	O
security	O
viewpoint	B-Architecture
model	I-Architecture
contains	O
those	O
elements	O
that	O
are	O
related	O
to	O
security	O
from	O
a	O
more	O
general	O
model	O
of	O
a	O
system	O
.	O
</s>
<s>
A	O
view	B-Algorithm
allows	O
a	O
user	O
to	O
examine	O
a	O
portion	O
of	O
a	O
particular	O
interest	O
area	O
.	O
</s>
<s>
For	O
example	O
,	O
an	O
Information	O
View	B-Algorithm
may	O
present	O
all	O
functions	O
,	O
organizations	O
,	O
technology	O
,	O
etc	O
.	O
</s>
<s>
that	O
use	O
a	O
particular	O
piece	O
of	O
information	O
,	O
while	O
the	O
Organizational	O
View	B-Algorithm
may	O
present	O
all	O
functions	O
,	O
technology	O
,	O
and	O
information	O
of	O
concern	O
to	O
a	O
particular	O
organization	O
.	O
</s>
<s>
In	O
the	O
Zachman	B-Library
Framework	I-Library
views	O
comprise	O
a	O
group	O
of	O
work	O
products	O
whose	O
development	O
requires	O
a	O
particular	O
analytical	O
and	O
technical	O
expertise	O
because	O
they	O
focus	O
on	O
either	O
the	O
“	O
what	O
,	O
”	O
“	O
how	O
,	O
”	O
“	O
who	O
,	O
”	O
“	O
where	O
,	O
”	O
“	O
when	O
,	O
”	O
or	O
“	O
why	O
”	O
of	O
the	O
enterprise	O
.	O
</s>
<s>
For	O
example	O
,	O
Functional	O
View	B-Algorithm
work	O
products	O
answer	O
the	O
question	O
“	O
how	O
is	O
the	O
mission	O
carried	O
out	O
?	O
”	O
They	O
are	O
most	O
easily	O
developed	O
by	O
experts	O
in	O
functional	B-Algorithm
decomposition	I-Algorithm
using	O
process	O
and	O
activity	O
modeling	O
.	O
</s>
<s>
They	O
show	O
the	O
enterprise	O
from	O
the	O
point	O
of	O
view	B-Algorithm
of	O
functions	O
.	O
</s>
<s>
In	O
ISO/IEC	O
42010:2007	O
(	O
IEEE-Std-1471-2000	B-Architecture
)	O
a	O
viewpoint	O
is	O
a	O
specification	B-Application
for	O
an	O
individual	O
view	B-Algorithm
.	O
</s>
<s>
A	O
view	B-Algorithm
is	O
a	O
representation	O
of	O
a	O
whole	O
system	O
from	O
the	O
perspective	B-Architecture
of	O
a	O
viewpoint	O
.	O
</s>
<s>
A	O
view	B-Algorithm
may	O
consist	O
of	O
one	O
or	O
more	O
architectural	B-Architecture
models	I-Architecture
.	O
</s>
<s>
Each	O
perspective	B-Architecture
has	O
a	O
different	O
focus	O
,	O
conceptualization	O
,	O
dedication	O
and	O
visualization	O
of	O
what	O
the	O
model	O
is	O
representing	O
.	O
</s>
<s>
Such	O
a	O
model	O
is	O
said	O
to	O
be	O
a	O
viewpoint	B-Architecture
model	I-Architecture
,	O
or	O
a	O
view	B-Algorithm
of	O
the	O
system	O
from	O
that	O
viewpoint	O
.	O
</s>
<s>
A	O
given	O
view	B-Algorithm
is	O
a	O
specification	B-Application
for	O
the	O
system	O
at	O
a	O
particular	O
level	O
of	O
abstraction	O
from	O
a	O
given	O
viewpoint	O
.	O
</s>
<s>
Lower-level	O
views	O
allow	O
the	O
engineer	O
to	O
concentrate	O
on	O
a	O
part	O
of	O
the	O
design	O
and	O
develop	O
the	O
detailed	O
specifications	B-Application
.	O
</s>
<s>
In	O
the	O
system	O
itself	O
,	O
however	O
,	O
all	O
of	O
the	O
specifications	B-Application
appearing	O
in	O
the	O
various	O
viewpoint	B-Architecture
models	I-Architecture
must	O
be	O
addressed	O
in	O
the	O
realized	O
components	O
of	O
the	O
system	O
.	O
</s>
<s>
And	O
the	O
specifications	B-Application
for	O
any	O
given	O
component	O
may	O
be	O
drawn	O
from	O
many	O
different	O
viewpoints	O
.	O
</s>
<s>
On	O
the	O
other	O
hand	O
,	O
the	O
specifications	B-Application
induced	O
by	O
the	O
distribution	O
of	O
functions	O
over	O
specific	O
components	O
and	O
component	O
interactions	O
will	O
typically	O
reflect	O
a	O
different	O
partitioning	O
of	O
concerns	O
than	O
that	O
reflected	O
in	O
the	O
original	O
viewpoints	O
.	O
</s>
<s>
An	O
architecture	B-Architecture
description	I-Architecture
is	O
a	O
representation	O
of	O
a	O
system	B-Architecture
architecture	I-Architecture
,	O
at	O
any	O
time	O
,	O
in	O
terms	O
of	O
its	O
component	O
parts	O
,	O
how	O
those	O
parts	O
function	O
,	O
the	O
rules	O
and	O
constraints	O
under	O
which	O
those	O
parts	O
function	O
,	O
and	O
how	O
those	O
parts	O
relate	O
to	O
each	O
other	O
and	O
to	O
the	O
environment	O
.	O
</s>
<s>
In	O
an	O
architecture	B-Architecture
description	I-Architecture
the	O
architecture	O
data	O
is	O
shared	O
across	O
several	O
views	O
and	O
products	O
.	O
</s>
<s>
Views	O
provide	O
the	O
ability	O
to	O
visualize	O
architecture	O
data	O
that	O
stem	O
across	O
products	O
,	O
logically	O
organizing	O
the	O
data	O
for	O
a	O
specific	O
or	O
holistic	O
perspective	B-Architecture
of	O
the	O
architecture	O
.	O
</s>
<s>
The	O
Three-schema	B-Application
approach	I-Application
for	O
data	O
modeling	O
,	O
introduced	O
in	O
1977	O
,	O
can	O
be	O
considered	O
one	O
of	O
the	O
first	O
view	B-Architecture
models	I-Architecture
.	O
</s>
<s>
It	O
is	O
an	O
approach	O
to	O
building	O
information	O
systems	O
and	O
systems	O
information	O
management	O
,	O
that	O
promotes	O
the	O
conceptual	B-Application
model	I-Application
as	O
the	O
key	O
to	O
achieving	O
data	B-General_Concept
integration	I-General_Concept
.	O
</s>
<s>
The	O
Three	B-Application
schema	I-Application
approach	I-Application
defines	O
three	O
schemas	O
and	O
views	O
:	O
</s>
<s>
At	O
the	O
center	O
,	O
the	O
conceptual	B-Application
schema	I-Application
defines	O
the	O
ontology	B-Language
of	O
the	O
concepts	O
as	O
the	O
users	O
think	O
of	O
them	O
and	O
talk	O
about	O
them	O
.	O
</s>
<s>
The	O
physical	O
schema	O
describes	O
the	O
internal	O
formats	O
of	O
the	O
data	O
stored	O
in	O
the	O
database	O
,	O
and	O
the	O
external	O
schema	O
defines	O
the	O
view	B-Algorithm
of	O
the	O
data	O
presented	O
to	O
the	O
application	B-Application
programs	I-Application
.	O
</s>
<s>
However	O
,	O
for	O
the	O
most	O
part	O
,	O
the	O
traditional	O
approach	O
to	O
building	O
systems	O
has	O
only	O
focused	O
on	O
defining	O
data	O
from	O
two	O
distinct	O
views	O
,	O
the	O
"	O
user	O
view	B-Algorithm
"	O
and	O
the	O
"	O
computer	O
view	B-Algorithm
"	O
.	O
</s>
<s>
From	O
the	O
user	O
view	B-Algorithm
,	O
which	O
will	O
be	O
referred	O
to	O
as	O
the	O
“	O
external	O
schema	O
,	O
”	O
the	O
definition	O
of	O
data	O
is	O
in	O
the	O
context	O
of	O
reports	O
and	O
screens	O
designed	O
to	O
aid	O
individuals	O
in	O
doing	O
their	O
specific	O
jobs	O
.	O
</s>
<s>
The	O
required	O
structure	O
of	O
data	O
from	O
a	O
usage	O
view	B-Algorithm
changes	O
with	O
the	O
business	O
environment	O
and	O
the	O
individual	O
preferences	O
of	O
the	O
user	O
.	O
</s>
<s>
From	O
the	O
computer	O
view	B-Algorithm
,	O
which	O
will	O
be	O
referred	O
to	O
as	O
the	O
“	O
internal	O
schema	O
,	O
”	O
data	O
is	O
defined	O
in	O
terms	O
of	O
file	O
structures	O
for	O
storage	O
and	O
retrieval	O
.	O
</s>
<s>
The	O
required	O
structure	O
of	O
data	O
for	O
computer	B-General_Concept
storage	I-General_Concept
depends	O
upon	O
the	O
specific	O
computer	O
technology	O
employed	O
and	O
the	O
need	O
for	O
efficient	O
processing	O
of	O
data	O
.	O
</s>
<s>
4+1	B-Architecture
is	O
a	O
view	B-Architecture
model	I-Architecture
designed	O
by	O
Philippe	O
Kruchten	O
in	O
1995	O
for	O
describing	O
the	O
architecture	O
of	O
software-intensive	O
systems	O
,	O
based	O
on	O
the	O
use	O
of	O
multiple	O
,	O
concurrent	O
views	O
.	O
</s>
<s>
The	O
four	O
views	O
of	O
the	O
model	O
are	O
logical	O
,	O
development	O
,	O
process	O
and	O
physical	O
view	B-Algorithm
:	O
</s>
<s>
Logical	O
view	B-Algorithm
:	O
is	O
concerned	O
with	O
the	O
functionality	O
that	O
the	O
system	O
provides	O
to	O
end-users	O
.	O
</s>
<s>
Development	O
view	B-Algorithm
:	O
illustrates	O
a	O
system	O
from	O
a	O
programmers	O
perspective	B-Architecture
and	O
is	O
concerned	O
with	O
software	O
management	O
.	O
</s>
<s>
Process	O
view	B-Algorithm
:	O
deals	O
with	O
the	O
dynamic	O
aspect	O
of	O
the	O
system	O
,	O
explains	O
the	O
system	O
processes	O
and	O
how	O
they	O
communicate	O
,	O
and	O
focuses	O
on	O
the	O
runtime	O
behavior	O
of	O
the	O
system	O
.	O
</s>
<s>
Physical	O
view	B-Algorithm
:	O
depicts	O
the	O
system	O
from	O
a	O
system	O
engineer	O
's	O
point	O
of	O
view	B-Algorithm
.	O
</s>
<s>
In	O
addition	O
selected	O
use	B-Architecture
cases	I-Architecture
or	O
scenarios	O
are	O
utilized	O
to	O
illustrate	O
the	O
architecture	O
.	O
</s>
<s>
Hence	O
the	O
model	O
contains	O
4+1	B-Architecture
views	O
.	O
</s>
<s>
Enterprise	B-Library
architecture	I-Library
framework	I-Library
defines	O
how	O
to	O
organize	O
the	O
structure	O
and	O
views	O
associated	O
with	O
an	O
enterprise	O
architecture	O
.	O
</s>
<s>
To	O
manage	O
this	O
scale	O
and	O
complexity	O
,	O
an	O
Architecture	B-Architecture
Framework	I-Architecture
provides	O
tools	O
and	O
methods	O
that	O
can	O
bring	O
the	O
task	O
into	O
focus	O
and	O
allow	O
valuable	O
artifacts	O
to	O
be	O
produced	O
when	O
they	O
are	O
most	O
needed	O
.	O
</s>
<s>
Architecture	B-Architecture
Frameworks	I-Architecture
are	O
commonly	O
used	O
in	O
Information	B-General_Concept
technology	I-General_Concept
and	O
Information	O
system	O
governance	O
.	O
</s>
<s>
The	O
Zachman	B-Library
Framework	I-Library
,	O
originally	O
conceived	O
by	O
John	O
Zachman	O
at	O
IBM	O
in	O
1987	O
,	O
is	O
a	O
framework	O
for	O
enterprise	O
architecture	O
,	O
which	O
provides	O
a	O
formal	O
and	O
highly	O
structured	O
way	O
of	O
viewing	O
and	O
defining	O
an	O
enterprise	O
.	O
</s>
<s>
These	O
artifacts	O
may	O
include	O
design	O
documents	O
,	O
specifications	B-Application
,	O
and	O
models	O
.	O
</s>
<s>
The	O
Zachman	B-Library
Framework	I-Library
is	O
often	O
referenced	O
as	O
a	O
standard	O
approach	O
for	O
expressing	O
the	O
basic	O
elements	O
of	O
enterprise	O
architecture	O
.	O
</s>
<s>
The	O
Zachman	B-Library
Framework	I-Library
has	O
been	O
recognized	O
by	O
the	O
U.S.	O
Federal	O
Government	O
as	O
having	O
"	O
received	O
...	O
worldwide	O
acceptance	O
as	O
an	O
integrated	O
framework	O
for	O
managing	O
change	O
in	O
enterprises	O
and	O
the	O
systems	O
that	O
support	O
them.	O
"	O
</s>
<s>
The	O
International	O
Organization	O
for	O
Standardization	O
(	O
ISO	O
)	O
Reference	B-Operating_System
Model	I-Operating_System
for	I-Operating_System
Open	I-Operating_System
Distributed	I-Operating_System
Processing	I-Operating_System
(	O
RM-ODP	B-Operating_System
)	O
specifies	O
a	O
set	O
of	O
viewpoints	O
for	O
partitioning	O
the	O
design	O
of	O
a	O
distributed	O
software/hardware	O
system	O
.	O
</s>
<s>
The	O
RMODP	B-Operating_System
viewpoints	O
are	O
:	O
</s>
<s>
RMODP	B-Operating_System
further	O
defines	O
a	O
requirement	O
for	O
a	O
design	O
to	O
contain	O
specifications	B-Application
of	O
consistency	O
between	O
viewpoints	O
,	O
including	O
:	O
</s>
<s>
The	O
Department	O
of	O
Defense	O
Architecture	B-Architecture
Framework	I-Architecture
(	O
DoDAF	O
)	O
defines	O
a	O
standard	O
way	O
to	O
organize	O
an	O
enterprise	O
architecture	O
(	O
EA	O
)	O
or	O
systems	B-Architecture
architecture	I-Architecture
into	O
complementary	O
and	O
consistent	O
views	O
.	O
</s>
<s>
and	O
assimilating	O
the	O
broad	O
scope	O
and	O
complexities	O
of	O
an	O
architecture	B-Architecture
description	I-Architecture
through	O
graphic	O
,	O
</s>
<s>
Overarching	O
All	O
View	B-Algorithm
(	O
AV	O
)	O
,	O
</s>
<s>
Operational	O
View	B-Algorithm
(	O
OV	O
)	O
,	O
</s>
<s>
Technical	O
Standards	O
View	B-Algorithm
(	O
TV	O
)	O
.	O
</s>
<s>
Each	O
view	B-Algorithm
depicts	O
certain	O
perspectives	O
of	O
an	O
architecture	O
as	O
described	O
below	O
.	O
</s>
<s>
The	O
figure	O
represents	O
the	O
information	O
that	O
links	O
the	O
operational	O
view	B-Algorithm
,	O
systems	O
and	O
services	O
view	B-Algorithm
,	O
and	O
technical	O
standards	O
view	B-Algorithm
.	O
</s>
<s>
In	O
the	O
US	O
Federal	B-Library
Enterprise	I-Library
Architecture	I-Library
enterprise	O
,	O
segment	O
,	O
and	O
solution	O
architecture	O
provide	O
different	O
business	O
perspectives	O
by	O
varying	O
the	O
level	O
of	O
detail	O
and	O
addressing	O
related	O
but	O
distinct	O
concerns	O
.	O
</s>
<s>
The	O
Federal	B-Library
Enterprise	I-Library
Architecture	I-Library
Practice	O
Guidance	O
(	O
2006	O
)	O
has	O
defined	O
three	O
types	O
of	O
architecture	O
:	O
</s>
<s>
From	O
an	O
investment	O
perspective	B-Architecture
,	O
EA	O
is	O
used	O
to	O
drive	O
decisions	O
about	O
the	O
IT	O
investment	O
portfolio	O
as	O
a	O
whole	O
.	O
</s>
<s>
From	O
an	O
investment	O
perspective	B-Architecture
,	O
segment	O
architecture	O
drives	O
decisions	O
for	O
a	O
business	O
case	O
or	O
group	O
of	O
business	O
cases	O
supporting	O
a	O
core	O
mission	O
area	O
or	O
common	O
or	O
shared	O
service	O
.	O
</s>
<s>
In	O
search	O
of	O
"	O
Framework	O
for	O
Modeling	O
Space	O
Systems	B-Architecture
Architectures	I-Architecture
"	O
Peter	O
Shames	O
and	O
Joseph	O
Skipper	O
(	O
2006	O
)	O
defined	O
a	O
"	O
nominal	O
set	O
of	O
views	O
"	O
,	O
Derived	O
from	O
CCSDS	O
RASDS	O
,	O
RM-ODP	B-Operating_System
,	O
ISO	B-Operating_System
10746	I-Operating_System
and	O
compliant	O
with	O
IEEE	B-Architecture
1471	I-Architecture
.	O
</s>
<s>
Note	O
that	O
for	O
some	O
analyses	O
elements	O
from	O
multiple	O
viewpoints	O
may	O
be	O
combined	O
into	O
a	O
new	O
view	B-Algorithm
,	O
possibly	O
using	O
a	O
layered	O
representation	O
.	O
</s>
<s>
In	O
a	O
latter	O
presentation	O
this	O
nominal	O
set	O
of	O
views	O
was	O
presented	O
as	O
an	O
Extended	O
RASDS	O
Semantic	O
Information	B-Application
Model	I-Application
Derivation	O
.	O
</s>
<s>
Organization	O
view	B-Algorithm
–	O
Includes	O
organizational	O
elements	O
and	O
their	O
structures	O
and	O
relationships	O
.	O
</s>
<s>
Requirements	O
view	B-Algorithm
–	O
Describes	O
the	O
requirements	O
,	O
goals	O
,	O
and	O
objectives	O
that	O
drive	O
the	O
system	O
.	O
</s>
<s>
Scenario	O
view	B-Algorithm
–	O
Describes	O
the	O
way	O
that	O
the	O
system	O
is	O
intended	O
to	O
be	O
used	O
,	O
see	O
scenario	O
planning	O
.	O
</s>
<s>
Metamodel	O
view	B-Algorithm
–	O
An	O
abstract	O
view	B-Algorithm
that	O
defines	O
information	B-Application
model	I-Application
elements	O
and	O
their	O
structures	O
and	O
relationships	O
.	O
</s>
<s>
Information	O
view	B-Algorithm
–	O
Describes	O
the	O
actual	O
data	O
and	O
information	O
as	O
it	O
is	O
realized	O
and	O
manipulated	O
within	O
the	O
system	O
.	O
</s>
<s>
Data	O
elements	O
are	O
defined	O
by	O
the	O
metamodel	O
view	B-Algorithm
and	O
they	O
are	O
referred	O
to	O
by	O
functional	O
objects	O
in	O
other	O
views	O
.	O
</s>
<s>
Functional	O
Dataflow	O
view	B-Algorithm
–	O
An	O
abstract	O
view	B-Algorithm
that	O
describes	O
the	O
functional	O
elements	O
in	O
the	O
system	O
,	O
their	O
interactions	O
,	O
behavior	O
,	O
provided	O
services	O
,	O
constraints	O
and	O
data	O
flows	O
among	O
them	O
.	O
</s>
<s>
Functional	O
Control	O
view	B-Algorithm
–	O
Describes	O
the	O
control	O
flows	O
and	O
interactions	O
among	O
functional	O
elements	O
within	O
the	O
system	O
.	O
</s>
<s>
Data	O
System	O
view	B-Algorithm
–	O
Describes	O
instruments	O
,	O
computers	O
,	O
and	O
data	O
storage	O
components	O
,	O
their	O
data	O
system	O
attributes	O
and	O
the	O
communications	O
connectors	O
(	O
busses	O
,	O
networks	O
,	O
point	O
to	O
point	O
links	O
)	O
that	O
are	O
used	O
in	O
the	O
system	O
.	O
</s>
<s>
Telecomm	O
view	B-Algorithm
–	O
Describes	O
the	O
telecomm	O
components	O
(	O
antenna	O
,	O
transceiver	O
)	O
,	O
their	O
attributes	O
and	O
their	O
connectors	O
(	O
RF	O
or	O
optical	O
links	O
)	O
.	O
</s>
<s>
Thermal	O
view	B-Algorithm
–	O
Describes	O
the	O
active	O
and	O
passive	O
thermal	O
components	O
in	O
the	O
system	O
(	O
radiators	O
,	O
coolers	O
,	O
vents	O
)	O
and	O
their	O
connectors	O
(	O
physical	O
and	O
free	O
space	O
radiation	O
)	O
and	O
attributes	O
,	O
along	O
with	O
the	O
thermal	O
properties	O
of	O
other	O
components	O
(	O
i.e.	O
</s>
<s>
Software	O
view	B-Algorithm
-	O
Describes	O
the	O
software	B-General_Concept
engineering	I-General_Concept
aspects	O
of	O
the	O
system	O
,	O
software	O
design	O
and	O
implementation	O
of	O
functionality	O
within	O
software	O
components	O
,	O
select	O
languages	O
and	O
libraries	O
to	O
be	O
used	O
,	O
define	O
APIs	O
,	O
do	O
the	O
engineering	O
of	O
abstract	O
functional	O
objects	O
into	O
tangible	O
software	O
elements	O
.	O
</s>
<s>
Communications	O
Protocol	O
view	B-Algorithm
–	O
Describes	O
the	O
end	O
to	O
end	O
design	O
of	O
the	O
communications	O
protocols	O
and	O
related	O
data	O
transport	O
and	O
data	O
management	O
services	O
,	O
shows	O
the	O
protocol	O
stacks	O
as	O
they	O
are	O
implemented	O
on	O
each	O
of	O
the	O
physical	O
components	O
of	O
the	O
system	O
.	O
</s>
<s>
Integration	O
and	O
Test	O
view	B-Algorithm
–	O
Looks	O
at	O
the	O
system	O
from	O
the	O
perspective	B-Architecture
of	O
what	O
must	O
be	O
done	O
to	O
assemble	O
,	O
integrate	O
and	O
test	O
system	O
and	O
sub-systems	O
,	O
and	O
assemblies	O
.	O
</s>
<s>
IV&V	O
view	B-Algorithm
–	O
independent	O
validation	O
and	O
verification	O
of	O
functionality	O
and	O
proper	O
operation	O
of	O
the	O
system	O
in	O
satisfaction	O
of	O
requirements	O
.	O
</s>
<s>
Standards	O
view	B-Algorithm
–	O
Defines	O
the	O
standards	O
to	O
be	O
adopted	O
during	O
design	O
of	O
the	O
system	O
(	O
e.g.	O
</s>
<s>
Infrastructure	O
view	B-Algorithm
–	O
Defines	O
the	O
infrastructure	O
elements	O
that	O
are	O
to	O
support	O
the	O
engineering	O
,	O
design	O
,	O
and	O
fabrication	O
process	O
.	O
</s>
<s>
Technology	O
Development	O
&	O
Assessment	O
view	B-Algorithm
–	O
Includes	O
description	O
of	O
technology	O
development	O
programs	O
designed	O
to	O
produce	O
algorithms	O
or	O
components	O
that	O
may	O
be	O
included	O
in	O
a	O
system	O
development	O
project	O
.	O
</s>
<s>
In	O
contrast	O
to	O
the	O
previous	O
listed	O
view	B-Architecture
models	I-Architecture
,	O
this	O
"	O
nominal	O
set	O
of	O
views	O
"	O
lists	O
a	O
whole	O
range	O
of	O
views	O
,	O
possible	O
to	O
develop	O
powerful	O
and	O
extensible	O
approaches	O
for	O
describing	O
a	O
general	O
class	O
of	O
software	O
intensive	O
system	B-Architecture
architectures	I-Architecture
.	O
</s>
