<s>
ALCS	O
,	O
which	O
stands	O
for	O
Airline	B-Application
Control	I-Application
System	I-Application
,	O
is	O
an	O
application	O
server	O
that	O
provides	O
industrial-strength	O
,	O
online	O
transaction	O
management	O
for	O
mission-critical	O
applications	O
.	O
</s>
<s>
ALCS	O
is	O
a	O
transaction	O
processing	O
monitor	O
for	O
the	O
IBM	B-Application
System/360	I-Application
,	O
System/370	B-Device
,	O
ESA/390	B-Device
,	O
and	O
zSeries	O
mainframes	O
.	O
</s>
<s>
It	O
is	O
a	O
variant	O
of	O
TPF	B-Operating_System
specially	O
designed	O
to	O
provide	O
all	O
the	O
benefits	O
of	O
TPF	B-Operating_System
(	O
very	O
high	O
speed	O
,	O
high	O
volume	O
,	O
and	O
high	O
availability	O
in	O
transaction	O
processing	O
)	O
but	O
with	O
the	O
advantages	O
such	O
as	O
easier	O
integration	O
into	O
the	O
data	O
center	O
offered	O
by	O
running	O
on	O
a	O
standard	O
IBM	O
operating	O
system	O
platform	O
.	O
</s>
<s>
Like	O
TPF	B-Operating_System
,	O
it	O
is	O
primarily	O
used	O
in	O
the	O
airline	O
,	O
hotel	O
,	O
and	O
banking	O
industries	O
.	O
</s>
<s>
Whereas	O
TPF	B-Operating_System
runs	O
as	O
a	O
stand-alone	O
OS	O
,	O
ALCS	O
is	O
designed	O
to	O
run	O
as	O
an	O
application	O
on	O
top	O
of	O
MVS/OS/390/z/OS	O
.	O
</s>
<s>
However	O
,	O
the	O
API	O
it	O
provides	O
to	O
applications	O
is	O
very	O
similar	O
to	O
that	O
on	O
TPF	B-Operating_System
,	O
so	O
applications	O
written	O
for	O
TPF	B-Operating_System
can	O
run	O
on	O
ALCS	O
with	O
minimal	O
modifications	O
:	O
typically	O
fewer	O
modifications	O
than	O
are	O
required	O
to	O
move	O
from	O
one	O
release	O
of	O
TPF	B-Operating_System
to	O
another	O
.	O
</s>
<s>
ALCS	O
2.3.1	O
runs	O
on	O
OS/390	B-Application
2.10	O
and	O
z/OS	B-Application
.	O
</s>
<s>
For	O
example	O
,	O
to	O
enable	O
MQSeries	B-Application
for	O
TPF	B-Operating_System
required	O
the	O
porting	O
,	O
modification	O
,	O
and	O
authoring	O
of	O
large	O
volumes	O
of	O
code	O
.	O
</s>
<s>
To	O
enable	O
this	O
on	O
ALCS	O
,	O
only	O
an	O
interface	O
to	O
the	O
MQ	O
product	O
on	O
z/OS	B-Application
needed	O
to	O
be	O
written	O
.	O
</s>
<s>
And	O
any	O
enhancements	O
made	O
to	O
MQ	B-Application
Series	I-Application
on	O
z/OS	B-Application
by	O
the	O
MQ	O
team	O
are	O
available	O
without	O
any	O
additional	O
work	O
on	O
the	O
part	O
of	O
the	O
ALCS	O
development	O
team	O
.	O
</s>
<s>
This	O
also	O
applies	O
to	O
TCP/IP	B-Protocol
,	O
Db2	B-Application
,	O
VTAM	B-Application
,	O
to	O
a	O
certain	O
extent	O
language	O
support	O
and	O
even	O
basic	O
disk	O
I/O	O
.	O
</s>
