<s>
Service-oriented	B-Application
programming	I-Application
(	O
SOP	O
)	O
is	O
a	O
programming	O
paradigm	O
that	O
uses	O
"	O
services	O
"	O
as	O
the	O
unit	O
of	O
computer	O
work	O
,	O
to	O
design	O
and	O
implement	O
integrated	O
business	O
applications	O
and	O
mission	B-Application
critical	I-Application
software	O
programs	O
.	O
</s>
<s>
While	O
SOA	O
focuses	O
on	O
communication	O
between	O
systems	O
using	O
"	O
services	O
"	O
,	O
SOP	O
provides	O
a	O
new	O
technique	O
to	O
build	O
agile	O
application	O
modules	B-General_Concept
using	O
in-memory	O
services	O
as	O
the	O
unit	O
of	O
work	O
.	O
</s>
<s>
In	O
SOP	O
,	O
the	O
design	O
of	O
the	O
programs	O
pivot	O
around	O
the	O
semantics	B-Application
of	O
service	O
calls	O
,	O
logical	O
routing	O
and	O
data	O
flow	O
description	O
across	O
well-defined	O
service	O
interfaces	B-Application
.	O
</s>
<s>
All	O
SOP	O
program	O
modules	B-General_Concept
are	O
encapsulated	O
as	O
services	O
and	O
a	O
service	O
can	O
be	O
composed	O
of	O
other	O
nested	O
services	O
in	O
a	O
hierarchical	O
manner	O
with	O
virtually	O
limitless	O
depth	O
to	O
this	O
service	O
stack	O
hierarchy	O
.	O
</s>
<s>
While	O
SOP	O
supports	O
the	O
basic	O
programming	O
constructs	O
for	O
sequencing	O
,	O
selection	O
and	O
iteration	O
,	O
it	O
is	O
differentiated	O
with	O
a	O
slew	O
of	O
new	O
programming	O
constructs	O
that	O
provide	O
built-in	O
native	O
ability	O
geared	O
towards	O
data	O
list	O
manipulation	O
,	O
data	B-General_Concept
integration	I-General_Concept
,	O
automated	O
multithreading	B-Operating_System
of	O
service	O
modules	B-General_Concept
,	O
declarative	O
context	O
management	O
and	O
synchronization	O
of	O
services	O
.	O
</s>
<s>
SOP	O
design	O
enables	O
programmers	O
to	O
semantically	O
synchronize	O
the	O
execution	O
of	O
services	O
in	O
order	O
to	O
guarantee	O
that	O
it	O
is	O
correct	O
,	O
or	O
to	O
declare	O
a	O
service	O
module	O
as	O
a	O
transaction	B-General_Concept
boundary	O
with	O
automated	O
commit/rollback	O
behavior	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
service	O
virtual	O
machine	O
(	O
SVM	O
)	O
that	O
automatically	O
creates	O
service	O
objects	O
as	O
units	O
of	O
work	O
and	O
manages	O
their	O
context	O
can	O
be	O
designed	O
to	O
run	O
based	O
on	O
the	O
SOP	O
program	O
metadata	O
stored	O
in	O
XML	B-Protocol
and	O
created	O
by	O
a	O
design-time	O
automation	O
tool	O
.	O
</s>
<s>
Automate	O
multi-threading	O
and	O
virtualization	B-Operating_System
of	O
applications	O
at	O
the	O
granular	O
(	O
unit-of-work	O
)	O
level	O
.	O
</s>
<s>
In	O
SOP	O
,	O
in-memory	O
software	O
modules	B-General_Concept
are	O
strictly	O
encapsulated	O
through	O
well-defined	O
service	O
interfaces	B-Application
that	O
can	O
be	O
externalized	O
on-demand	O
as	O
web	O
service	O
operations	O
.	O
</s>
<s>
This	O
minimal	O
unit	O
of	O
encapsulation	O
maximizes	O
the	O
opportunities	O
for	O
reusability	B-Application
within	O
other	O
in-memory	O
service	O
modules	B-General_Concept
as	O
well	O
as	O
across	O
existing	O
and	O
legacy	B-Device
software	I-Device
assets	O
.	O
</s>
<s>
By	O
using	O
service	O
interfaces	B-Application
for	O
information	B-Application
hiding	I-Application
,	O
SOP	O
extends	O
the	O
service-oriented	O
design	O
principles	O
used	O
in	O
SOA	O
to	O
achieve	O
separation	O
of	O
concerns	O
across	O
in-memory	O
service	O
modules	B-General_Concept
.	O
</s>
<s>
A	O
service	O
interface	B-Application
in	O
SOP	O
is	O
an	O
in-memory	O
object	O
that	O
describes	O
a	O
well-defined	O
software	O
task	O
with	O
well-defined	O
input	O
and	O
output	O
data	B-General_Concept
structures	I-General_Concept
.	O
</s>
<s>
Service	O
interfaces	B-Application
can	O
be	O
grouped	O
into	O
packages	O
.	O
</s>
<s>
An	O
SOP	O
service	O
interface	B-Application
can	O
be	O
externalized	O
as	O
a	O
WSDL	O
operation	O
and	O
a	O
single	O
service	O
or	O
a	O
package	O
of	O
services	O
can	O
be	O
described	O
using	O
WSDL	O
.	O
</s>
<s>
Furthermore	O
,	O
service	O
interfaces	B-Application
can	O
be	O
assigned	O
to	O
one	O
or	O
many	O
service	O
groups	O
based	O
on	O
shared	O
properties	O
.	O
</s>
<s>
In	O
SOP	O
,	O
runtime	O
properties	O
stored	O
on	O
the	O
service	O
interface	B-Application
metadata	O
serve	O
as	O
a	O
contract	O
with	O
the	O
service	O
virtual	O
machine	O
(	O
SVM	O
)	O
.	O
</s>
<s>
A	O
service	O
interface	B-Application
can	O
be	O
declared	O
as	O
a	O
fully	O
synchronized	O
interface	B-Application
,	O
meaning	O
that	O
only	O
a	O
single	O
instance	O
of	O
that	O
service	O
can	O
run	O
at	O
any	O
given	O
time	O
.	O
</s>
<s>
Furthermore	O
,	O
synchronization	O
can	O
be	O
declared	O
across	O
services	O
interfaces	B-Application
that	O
belong	O
to	O
the	O
same	O
service	O
group	O
.	O
</s>
<s>
It	O
is	O
a	O
pluggable	O
in-memory	O
interface	B-Application
that	O
abstracts	O
the	O
location	O
of	O
a	O
service	O
producer	O
as	O
well	O
as	O
the	O
communication	O
protocol	O
,	O
used	O
between	O
the	O
consumer	O
and	O
producer	O
when	O
going	O
across	O
computer	O
memory	O
,	O
from	O
the	O
SOP	O
runtime	O
environment	O
such	O
as	O
an	O
SVM	O
.	O
</s>
<s>
The	O
use	O
of	O
a	O
service	O
invoker	O
in	O
SOP	O
is	O
the	O
key	O
to	O
location	B-Protocol
transparency	I-Protocol
and	O
virtualization	B-Operating_System
.	O
</s>
<s>
For	O
example	O
,	O
a	O
"	O
SOAP	B-Application
Invoker	O
"	O
is	O
the	O
default	O
service	O
invoker	O
for	O
remote	O
communication	O
across	O
machines	O
using	O
the	O
web	O
service	O
standards	O
.	O
</s>
<s>
It	O
is	O
a	O
pluggable	O
in-memory	O
interface	B-Application
that	O
abstracts	O
the	O
communication	O
protocol	O
for	O
incoming	O
service	O
requests	O
made	O
to	O
the	O
SOP	O
runtime	O
environment	O
such	O
as	O
the	O
SVM	O
.	O
</s>
<s>
It	O
is	O
important	O
to	O
note	O
that	O
Service	O
modules	B-General_Concept
built	O
through	O
the	O
SOP	O
paradigm	O
have	O
an	O
extroverted	O
nature	O
and	O
can	O
be	O
transparently	O
externalized	O
through	O
standards	O
such	O
as	O
SOAP	B-Application
or	O
any	O
proprietary	O
protocol	O
.	O
</s>
<s>
Furthermore	O
,	O
this	O
semantic-based	O
approach	O
can	O
be	O
layered	O
into	O
a	O
visual	O
environment	O
built	O
on	O
top	O
of	O
a	O
fully	O
metadata-driven	O
layer	O
for	O
storing	O
the	O
service	O
interface	B-Application
and	O
service	O
module	O
definitions	O
.	O
</s>
<s>
The	O
result	O
is	O
tremendous	O
productivity	O
gain	O
during	O
development	O
,	O
ease	O
of	O
testing	O
and	O
significant	O
agility	O
in	O
deployment	B-Application
.	O
</s>
<s>
If	O
you	O
look	O
inside	O
of	O
a	O
black-boxed	O
interface	B-Application
definition	O
of	O
a	O
composite	O
service	O
,	O
you	O
may	O
see	O
other	O
service	O
interfaces	B-Application
connected	O
to	O
each	O
other	O
and	O
connected	O
to	O
SOP	O
programming	O
constructs	O
.	O
</s>
<s>
Furthermore	O
,	O
SOP	O
supports	O
semantic	O
constructs	O
for	O
automatic	O
data	B-General_Concept
mapping	I-General_Concept
,	O
translation	O
,	O
manipulation	O
and	O
flow	O
across	O
inner	O
services	O
of	O
a	O
composite	O
service	O
.	O
</s>
<s>
For	O
example	O
,	O
a	O
configurable	O
construct	O
used	O
for	O
filtering	O
output	O
data	O
of	O
services	O
can	O
take	O
a	O
list	O
of	O
Sales	O
orders	O
,	O
Purchase	O
orders	O
or	O
any	O
other	O
data	B-General_Concept
structure	I-General_Concept
,	O
and	O
filter	O
its	O
data	O
based	O
on	O
user	O
declared	O
filter	O
properties	O
stored	O
on	O
the	O
interface	B-Application
of	O
that	O
instance	O
of	O
the	O
filter	O
construct	O
.	O
</s>
<s>
Furthermore	O
,	O
any	O
service	O
interface	B-Application
can	O
automatically	O
run	O
in	O
a	O
loop	O
or	O
"	O
foreach	O
"	O
mode	O
,	O
if	O
it	O
is	O
supplied	O
with	O
two	O
or	O
more	O
input	O
components	O
upon	O
automatic	O
preparation	O
.	O
</s>
<s>
This	O
behavior	O
is	O
supported	O
at	O
design-time	O
when	O
a	O
data	O
list	O
structure	O
from	O
one	O
service	O
is	O
connected	O
to	O
a	O
service	O
that	O
takes	O
a	O
single	O
data	B-General_Concept
structure	I-General_Concept
(	O
i.e.	O
</s>
<s>
If	O
a	O
runtime	O
property	O
of	O
the	O
composite	O
service	O
interface	B-Application
is	O
declared	O
to	O
support	O
"	O
foreach	O
"	O
in	O
parallel	O
,	O
then	O
the	O
runtime	O
automation	O
environment	O
can	O
automatically	O
multi-thread	O
the	O
loop	O
and	O
run	O
it	O
in	O
parallel	O
.	O
</s>
<s>
Data	B-General_Concept
mapping	I-General_Concept
,	O
translation	O
,	O
and	O
transformation	O
constructs	O
enable	O
automatic	O
transfer	O
of	O
data	O
across	O
inner	O
services	O
.	O
</s>
<s>
A	O
composite	O
service	O
can	O
be	O
declared	O
as	O
a	O
transaction	B-General_Concept
boundary	O
.	O
</s>
<s>
The	O
runtime	O
environment	O
for	O
SOP	O
automatically	O
creates	O
and	O
manages	O
a	O
hierarchical	O
context	O
for	O
composite	O
service	O
objects	O
which	O
are	O
used	O
as	O
a	O
transaction	B-General_Concept
boundary	O
.	O
</s>
<s>
When	O
a	O
composite	O
service	O
that	O
is	O
declared	O
as	O
a	O
transaction	B-General_Concept
boundary	O
fails	O
without	O
an	O
exception	O
handling	O
routing	O
,	O
the	O
SOP	O
runtime	O
environment	O
automatically	O
dispatches	O
the	O
compensation	O
services	O
associated	O
with	O
all	O
the	O
inner	O
services	O
which	O
have	O
already	O
executed	O
successfully	O
.	O
</s>
<s>
An	O
atomic	O
service	O
is	O
an	O
in-memory	O
extension	O
of	O
the	O
SOP	O
runtime	O
environment	O
through	O
a	O
service	O
native	O
interface	B-Application
(	O
SNI	O
)	O
it	O
is	O
essentially	O
a	O
plug-in	O
mechanism	O
.	O
</s>
<s>
An	O
example	O
of	O
a	O
service	O
plug-in	O
would	O
be	O
a	O
SOAP	B-Application
communicator	O
plug-in	O
that	O
can	O
on-the-fly	O
translate	O
any	O
in-memory	O
service	O
input	O
data	O
to	O
a	O
Web	O
Service	O
SOAP	B-Application
request	O
,	O
post	O
it	O
to	O
a	O
service	O
producer	O
,	O
and	O
then	O
translate	O
the	O
corresponding	O
SOAP	B-Application
response	O
to	O
in-memory	O
output	O
data	O
on	O
the	O
service	O
.	O
</s>
<s>
This	O
unique	O
,	O
component-level	O
virtualization	B-Operating_System
is	O
termed	O
"	O
service	O
grid	B-Architecture
virtualization	B-Operating_System
"	O
in	O
order	O
to	O
distinguish	O
it	O
from	O
traditional	O
application	O
,	O
or	O
process-level	O
virtualization	B-Operating_System
.	O
</s>
<s>
SOP	O
presents	O
significant	O
opportunities	O
to	O
support	O
cross-cutting	B-Application
concerns	I-Application
for	O
all	O
applications	O
built	O
using	O
the	O
SOP	O
technique	O
.	O
</s>
<s>
Based	O
on	O
declared	O
key	O
input	O
values	O
of	O
a	O
service	O
instance	O
,	O
the	O
outputs	O
of	O
a	O
non	O
time-sensitive	O
inner	O
service	O
can	O
be	O
cached	B-General_Concept
by	O
the	O
SOP	O
runtime	O
environment	O
when	O
running	O
in	O
the	O
context	O
of	O
a	O
particular	O
composite	O
service	O
.	O
</s>
<s>
When	O
a	O
service	O
is	O
cached	B-General_Concept
for	O
particular	O
key	O
input	O
values	O
,	O
the	O
SOP	O
runtime	O
environment	O
fetches	O
the	O
cached	B-General_Concept
outputs	O
corresponding	O
to	O
the	O
keyed	O
inputs	O
from	O
its	O
service	O
cache	B-General_Concept
instead	O
of	O
consuming	O
the	O
service	O
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
ability	O
to	O
call	O
any	O
service	O
,	O
Service	O
Request	O
Events	O
and	O
Shared	B-Operating_System
Memory	I-Operating_System
are	O
two	O
of	O
the	O
SOP	O
built-in	O
mechanisms	O
provided	O
for	O
inter-service	O
communication	O
.	O
</s>
<s>
SOP	O
also	O
provides	O
a	O
shared	B-Operating_System
memory	I-Operating_System
space	O
with	O
access	O
control	O
where	O
services	O
can	O
access	O
and	O
update	O
a	O
well-defined	O
data	B-General_Concept
structure	I-General_Concept
that	O
is	O
similar	O
to	O
the	O
input/output	O
structure	O
of	O
services	O
.	O
</s>
<s>
The	O
shared	B-Operating_System
memory	I-Operating_System
mechanism	O
within	O
SOP	O
can	O
be	O
programmatically	O
accessed	O
through	O
service	O
interfaces	B-Application
.	O
</s>
<s>
This	O
feature	O
is	O
analogous	O
to	O
polymorphism	B-Application
in	I-Application
object-oriented	I-Application
programming	I-Application
.	O
</s>
<s>
Each	O
possible	O
override	O
implementation	O
can	O
be	O
associated	O
to	O
one	O
or	O
more	O
override	O
configuration	O
portfolios	O
in	O
order	O
to	O
manage	O
activation	O
of	O
groups	O
of	O
related	O
overrides	O
throughout	O
different	O
SOP	O
application	O
installations	O
at	O
the	O
time	O
of	O
deployment	B-Application
.	O
</s>
<s>
Select	O
services	O
can	O
be	O
deployed	O
securely	O
for	O
external	O
programmatic	O
consumption	O
by	O
a	O
presentation	O
(	O
GUI	B-Application
)	O
layer	O
,	O
or	O
other	O
applications	O
.	O
</s>
<s>
Standards	O
or	O
proprietary	O
authorization	O
and	O
communication	O
security	O
is	O
customized	O
through	O
service	O
overrides	O
,	O
plug-in	O
invoker	O
and	O
service	O
listener	O
modules	B-General_Concept
.	O
</s>
<s>
Since	O
all	O
artifacts	O
of	O
SOP	O
are	O
well-encapsulated	O
services	O
and	O
all	O
SOP	O
mechanisms	O
,	O
such	O
as	O
shared	B-Operating_System
memory	I-Operating_System
,	O
can	O
be	O
provided	O
as	O
distributable	O
services	O
,	O
large-scale	O
virtualization	B-Operating_System
can	O
be	O
automated	O
by	O
the	O
SOP	O
runtime	O
environment	O
.	O
</s>
<s>
The	O
term	O
service-oriented	B-Application
programming	I-Application
was	O
first	O
published	O
in	O
2002	O
by	O
Alberto	O
Sillitti	O
,	O
Tullio	O
Vernazza	O
and	O
Giancarlo	O
Succi	O
in	O
a	O
book	O
called	O
"	O
Software	O
Reuse	O
:	O
Methods	O
,	O
Techniques	O
,	O
and	O
Tools.	O
"	O
</s>
<s>
This	O
change	O
in	O
design	O
forces	O
a	O
change	O
in	O
the	O
way	O
we	O
develop	O
our	O
software	O
modules	B-General_Concept
and	O
applications	O
:	O
applications	O
must	O
be	O
written	O
for	O
concurrency	B-Operating_System
in	O
order	O
to	O
utilize	O
multi-core	B-Architecture
processors	I-Architecture
and	O
writing	O
concurrent	O
programs	O
is	O
a	O
challenging	O
task	O
.	O
</s>
<s>
SOP	O
provides	O
a	O
built-in	O
opportunity	O
for	O
automated	O
multithreading	B-Operating_System
.	O
</s>
<s>
Application	B-Operating_System
Virtualization	I-Operating_System
:	O
SOP	O
promotes	O
built-in	O
micro	O
control	O
over	O
location	B-Protocol
transparency	I-Protocol
of	O
the	O
service	O
constituents	O
of	O
any	O
service	O
module	O
.	O
</s>
<s>
This	O
results	O
in	O
automatic	O
and	O
granular	O
virtualization	B-Operating_System
of	O
application	O
components	O
(	O
versus	O
an	O
entire	O
application	O
process	O
)	O
across	O
a	O
cluster	B-Architecture
or	O
grid	B-Architecture
of	O
SOP	O
runtime	O
platforms	O
.	O
</s>
<s>
Software	B-Architecture
as	I-Architecture
a	I-Architecture
service	I-Architecture
(	O
SaaS	B-Architecture
)	O
:	O
capabilities	O
of	O
the	O
current	O
SaaS	B-Architecture
platforms	O
cannot	O
address	O
the	O
customization	O
and	O
integration	O
complexities	O
required	O
by	O
large	O
enterprises	O
.	O
</s>
<s>
This	O
will	O
drive	O
SOP	O
into	O
the	O
next	O
generation	O
SaaS	B-Architecture
platforms	O
.	O
</s>
