<s>
Data	B-Operating_System
Facility	I-Operating_System
Storage	I-Operating_System
Management	I-Operating_System
Subsystem	I-Operating_System
(	O
DFSMS	B-Operating_System
)	O
is	O
a	O
central	O
component	O
of	O
IBM	O
's	O
flagship	O
operating	O
system	O
z/OS	B-Application
.	O
</s>
<s>
Data	B-Operating_System
Facility	I-Operating_System
Storage	I-Operating_System
Management	I-Operating_System
Subsystem	I-Operating_System
is	O
also	O
a	O
collective	O
name	O
for	O
a	O
collection	O
of	O
several	O
products	O
,	O
all	O
but	O
two	O
of	O
which	O
are	O
included	O
in	O
the	O
DFSMS/MVS	O
product	O
.	O
</s>
<s>
In	O
1972	O
IBM	O
announced	O
the	O
first	O
release	O
of	O
the	O
OS/VS2	B-Application
operating	O
system	O
for	O
the	O
IBM	O
System	O
370	O
systems	O
;	O
that	O
release	O
later	O
was	O
known	O
as	O
Single	O
Virtual	O
Storage	O
(	O
SVS	B-Application
)	O
.	O
</s>
<s>
In	O
1974	O
IBM	O
announced	O
release	O
2.0	O
;	O
that	O
release	O
and	O
all	O
subsequent	O
releases	O
became	O
known	O
as	O
Multiple	B-Application
Virtual	I-Application
Storage	I-Application
(	O
MVS	B-Application
)	O
.	O
</s>
<s>
All	O
releases	O
of	O
OS/VS2	B-Application
were	O
available	O
to	O
no	O
charge	O
because	O
the	O
software	O
cost	O
was	O
bundled	O
with	O
the	O
hardware	O
cost	O
.	O
</s>
<s>
OS/VS2	B-Application
Release	O
3.8	O
was	O
the	O
last	O
free	O
release	O
of	O
MVS	B-Application
.	O
</s>
<s>
DFDS	O
supports	O
an	O
indexed	O
VTOC	B-Application
,	O
and	O
with	O
the	O
proper	O
PTF	O
supports	O
the	O
Speed	O
Matching	O
Buffer	O
on	O
the	O
IBM	O
3880	O
.	O
</s>
<s>
SAM-E	O
improves	O
the	O
performance	O
of	O
BPAM	O
,	O
BSAM	B-Application
and	O
QSAM	B-Application
on	O
direct	B-Application
access	I-Application
storage	I-Application
devices	I-Application
.	O
</s>
<s>
In	O
June	O
1980	O
,	O
IBM	O
announced	O
MVS/System	O
Product	O
(	O
MVS/SP	O
)	O
as	O
a	O
replacement	O
for	O
MVS/SE	O
.	O
</s>
<s>
IBM	O
also	O
announced	O
MVS/Extended	O
Architecture	O
(	O
MVS/XA	O
)	O
,	O
consisting	O
of	O
MVS/SP	O
Version	O
2	O
and	O
a	O
corequisite	O
new	O
product	O
,	O
Data	B-Application
Facility	I-Application
Product	I-Application
(	O
DFP	O
)	O
,	O
5665-284	O
,	O
replacing	O
five	O
of	O
the	O
products	O
listed	O
above	O
,	O
the	O
linkage	B-Application
editor	I-Application
and	O
the	O
loader	O
.	O
</s>
<s>
On	O
May	O
17	O
,	O
1983	O
,	O
IBM	O
announced	O
MVS/370	O
Data	B-Application
Facility	I-Application
Product	I-Application
(	O
MVS/370	O
DFP	O
)	O
,	O
5665-295	O
,	O
for	O
MVS/SP	O
Version	O
1	O
Release	O
3	O
,	O
replacing	O
the	O
same	O
five	O
programs	O
as	O
DFP	O
for	O
MVS/XA	O
.	O
</s>
<s>
On	O
February	O
5	O
,	O
1985	O
,	O
IBM	O
announced	O
MVS/XA	O
Data	B-Application
Facility	I-Application
Product	I-Application
(	O
MVS/XA	O
DFP	O
)	O
Version	O
2	O
,	O
5655-XA2	O
,	O
as	O
a	O
replacement	O
for	O
MVS/XA	O
Data	B-Application
Facility	I-Application
Product	I-Application
Version	O
1	O
,	O
5665-284	O
.	O
</s>
<s>
DFP	O
replaced	O
BDAM	O
,	O
BPAM	O
,	O
BSAM	B-Application
,	O
ISAM	O
,	O
QSAM	B-Application
and	O
VSAM	O
.	O
</s>
<s>
On	O
February	O
15	O
,	O
1988	O
IBM	O
announced	O
MVS/System	O
Product	O
Version	O
3	O
(	O
MVS/ESA	O
)	O
,	O
it	O
also	O
announced	O
MVS/Data	O
Facility	O
Product	O
Version	O
3	O
(	O
MVS/DFP	O
)	O
,	O
5665-XA3	O
;	O
MVS/SP	O
V3	O
required	O
either	O
MVS/XA	O
Data	B-Application
Facility	I-Application
Product	I-Application
Version	O
2	O
,	O
5655-XA2	O
,	O
or	O
Version	O
3	O
.	O
</s>
<s>
More	O
recent	O
releases	O
were	O
corequisites	O
for	O
MVS/ESA	O
SP	O
Version	O
4	O
and	O
MVS/ESA	O
SP	O
Version	O
5	O
.	O
</s>
<s>
In	O
addition	O
to	O
replacing	O
part	O
of	O
the	O
device	O
support	O
in	O
the	O
base	O
MVS/SP	O
,	O
DFP	O
replaces	O
the	O
Linkage	B-Application
Editor	I-Application
and	O
several	O
utility	B-Application
programs	I-Application
and	O
service	O
aids	O
.	O
</s>
<s>
On	O
May	O
19	O
,	O
1992	O
,	O
IBM	O
announced	O
DFSMS/MVS	O
,	O
5695-DF1	O
,	O
replacing	O
MVS/Data	O
Facility	O
Product	O
(	O
MVS/DFP	O
)	O
Version	O
3	O
,	O
5665-XA3	O
,	O
</s>
<s>
DFSMS/MVS	O
also	O
replaced	O
utilities	O
and	O
service	O
aids	O
.	O
</s>
<s>
DSDSS	O
and	O
DFHSM	O
became	O
optional	O
chargeable	O
features	O
of	O
DFSMS	B-Operating_System
;	O
DFSORT	B-Application
and	O
RACF	B-Application
remained	O
separate	O
products	O
.	O
</s>
<s>
While	O
DFSMS/MVS	O
Release	O
1	O
still	O
included	O
ISAM	O
,	O
IBM	O
eventually	O
dropped	O
it	O
,	O
but	O
continued	O
to	O
support	O
the	O
ISAM	O
compatibility	O
interface	O
to	O
VSAM	O
.	O
</s>
<s>
DFSMS/MVS	O
R1	O
included	O
the	O
optional	O
Removeable	O
Media	O
Manager	O
(	O
DFSMSrmm	O
)	O
,	O
which	O
supports	O
both	O
manual	O
tape	B-Device
libraries	I-Device
and	O
the	O
3495	O
Tape	B-Device
Library	I-Device
Dataserver	O
.	O
</s>
<s>
On	O
March	O
1	O
,	O
1994	O
,	O
IBM	O
announced	O
DFSMS/MVS	O
Release	O
2	O
.	O
</s>
<s>
On	O
March	O
1	O
,	O
1994	O
,	O
IBM	O
announced	O
DFSMS/MVS	O
Release	O
3	O
.	O
</s>
<s>
On	O
March	O
1	O
,	O
1994	O
,	O
IBM	O
announced	O
DFSMS/MVS	O
Release	O
4	O
.	O
</s>
<s>
On	O
March	O
1	O
,	O
1994	O
,	O
IBM	O
announced	O
DFSMS/MVS	O
Release	O
5	O
.	O
</s>
<s>
by	O
,	O
e.g.	O
,	O
DFDS	O
,	O
and	O
features	O
added	O
in	O
the	O
latest	O
release	O
of	O
z/OS	B-Application
.	O
</s>
<s>
DFSMSdss	O
is	O
a	O
chargeable	O
feature	O
of	O
DFSMS	B-Operating_System
that	O
can	O
dump	O
and	O
restore	O
selected	O
data	O
sets	O
and	O
selected	O
volumes	O
based	O
on	O
specifications	O
in	O
control	O
statements	O
.	O
</s>
<s>
DFSMSdfp	O
replaces	O
the	O
older	O
direct	O
,	O
index	O
and	O
sequential	O
access	O
methods	O
,	O
the	O
utilities	O
and	O
service	O
aids	O
,	O
the	O
linkage	B-Application
editor	I-Application
,	O
the	O
loader	O
and	O
program	O
fetch	O
.	O
</s>
<s>
The	O
VTOC	B-Application
structure	O
inherited	O
from	O
OS/360	B-Application
uses	O
records	O
with	O
44	O
byte	O
keys	O
,	O
and	O
a	O
sequential	O
search	O
using	O
a	O
Search	O
Key	O
Equal/TIC	O
*	O
-8	O
loop	O
.	O
</s>
<s>
The	O
VTOC	B-Application
Index	O
(	O
VTOCIX	O
)	O
is	O
an	O
optional	O
data	O
set	O
that	O
indexes	O
Data	B-Application
Set	I-Application
Control	I-Application
Blocks	I-Application
(	O
DSCBs	O
)	O
and	O
allows	O
a	O
faster	O
search	O
.	O
</s>
<s>
The	O
Improved	O
Catalog	O
Facility	O
(	O
ICF	O
)	O
replaces	O
the	O
OS/360	B-Application
Control	O
Volume	O
(	O
CVOL	O
)	O
and	O
the	O
VSAM	O
catalog	O
with	O
a	O
more	O
resilient	O
catalog	O
structure	O
.	O
</s>
<s>
Partitoned	O
Data	O
Set	O
Extended	O
(	O
PDSE	O
)	O
is	O
a	O
new	O
type	O
of	O
dataset	O
that	O
resolves	O
several	O
issues	O
with	O
the	O
old	O
PDS	O
organization	O
but	O
that	O
can	O
be	O
read	O
and	O
written	O
by	O
existing	O
BPAM	O
,	O
BSAM	B-Application
and	O
QSAM	B-Application
code	O
.	O
</s>
<s>
System	O
Managed	O
Storage	O
(	O
SMS	O
)	O
is	O
a	O
set	O
of	O
facilities	O
for	O
controlling	O
the	O
placement	O
,	O
migration	O
and	O
retention	O
of	O
datasets	O
on	O
direct	B-Application
access	I-Application
storage	I-Application
devices	I-Application
that	O
is	O
more	O
flexible	O
than	O
older	O
methods	O
,	O
e.g.	O
,	O
VOL	O
=	O
SER	O
specifications	O
in	O
JCL	O
.	O
</s>
<s>
The	O
Binder	O
is	O
a	O
program	O
similar	O
to	O
the	O
linkage	B-Application
editor	I-Application
that	O
can	O
also	O
manage	O
program	O
objects	O
on	O
a	O
PDSE	O
library	O
.	O
</s>
<s>
DFSMSdfp	O
provides	O
facilities	O
for	O
using	O
several	O
different	O
protocols	O
to	O
duplicate	O
or	O
mirror	O
DASD	B-Application
volumes	O
to	O
a	O
remote	O
location	O
.	O
</s>
<s>
Such	O
objects	O
are	O
sometimes	O
referred	O
to	O
as	O
BLOBs	B-General_Concept
.	O
</s>
<s>
DFSORT	B-Application
is	O
a	O
sort/merge	O
utility	O
that	O
is	O
part	O
of	O
the	O
DFSMS	B-Operating_System
family	O
but	O
not	O
part	O
of	O
the	O
DFSMS/MVS	O
product	O
.	O
</s>
<s>
DFSMShsm	O
,	O
originally	O
Hierarchical	O
Storage	O
Manager	O
(	O
HSM	O
)	O
,	O
5740-XRB	O
,	O
and	O
later	O
Data	O
Facility	O
Hierarchical	O
Storage	O
Manager	O
Version	O
2	O
(	O
DFHSM	O
)	O
,	O
5665-329	O
,	O
before	O
becoming	O
an	O
optional	O
component	O
of	O
DFSMS	B-Operating_System
,	O
is	O
a	O
utility	O
for	O
archiving	O
and	O
retrieving	O
datasets	O
.	O
</s>
<s>
RACF	B-Application
is	O
a	O
security	O
program	O
that	O
is	O
part	O
of	O
the	O
DFSMS	B-Operating_System
family	O
but	O
not	O
part	O
of	O
the	O
DFSMS/MVS	O
product	O
.	O
</s>
<s>
It	O
includes	O
an	O
API	O
called	O
SAF	O
that	O
allows	O
applications	O
to	O
do	O
authentication	O
and	O
to	O
check	O
access	O
privileges	O
,	O
and	O
also	O
includes	O
an	O
interface	O
to	O
LDAP	B-Protocol
.	O
</s>
<s>
The	O
Removable	O
Media	O
Manager	O
(	O
DFSMSDFSMSrmm	O
)	O
controls	O
libraries	O
of	O
tapes	O
,	O
whether	O
manually	O
mounted	O
on	O
tape	O
drive	O
or	O
stored	O
in	O
an	O
automated	B-Device
tape	I-Device
library	I-Device
.	O
</s>
