<s>
The	O
IBM	B-Device
7950	I-Device
,	O
also	O
known	O
as	O
Harvest	B-Device
,	O
was	O
a	O
one-of-a-kind	O
adjunct	O
to	O
the	O
Stretch	B-Device
computer	I-Device
which	O
was	O
installed	O
at	O
the	O
United	O
States	O
National	O
Security	O
Agency	O
(	O
NSA	O
)	O
.	O
</s>
<s>
Harvest	B-Device
was	O
designed	O
to	O
be	O
used	O
for	O
cryptanalysis	O
.	O
</s>
<s>
In	O
April	O
1958	O
,	O
the	O
final	O
design	O
for	O
the	O
NSA-customized	O
version	O
of	O
IBM	O
's	O
Stretch	B-Device
computer	I-Device
had	O
been	O
approved	O
,	O
and	O
the	O
machine	O
was	O
installed	O
in	O
February	O
1962	O
.	O
</s>
<s>
Harvest	B-Device
added	O
a	O
small	O
number	O
of	O
instructions	O
to	O
Stretch	O
,	O
and	O
could	O
not	O
operate	O
independently	O
.	O
</s>
<s>
An	O
NSA-conducted	O
evaluation	O
found	O
that	O
Harvest	B-Device
was	O
more	O
powerful	O
than	O
the	O
best	O
commercially	O
available	O
machine	O
by	O
a	O
factor	O
of	O
50	O
to	O
200	O
,	O
depending	O
on	O
the	O
task	O
.	O
</s>
<s>
The	O
equipment	O
added	O
to	O
the	O
Stretch	B-Device
computer	I-Device
consisted	O
of	O
the	O
following	O
special	O
peripherals	O
:	O
</s>
<s>
With	O
the	O
stream	O
processing	O
unit	O
,	O
Harvest	B-Device
was	O
able	O
to	O
process	O
3	O
million	O
characters	O
a	O
second	O
.	O
</s>
<s>
The	O
TRACTOR	O
tape	O
system	O
,	O
part	O
of	O
the	O
HARVEST	B-Device
system	O
,	O
was	O
unique	O
for	O
its	O
time	O
.	O
</s>
<s>
Harvest	B-Device
's	O
most	O
important	O
mode	O
of	O
operation	O
was	O
called	O
"	O
setup	O
"	O
mode	O
,	O
in	O
which	O
the	O
processor	O
was	O
configured	O
with	O
several	O
hundred	O
bits	O
of	O
information	O
and	O
the	O
processor	O
then	O
operated	O
by	O
streaming	O
data	O
from	O
memory	O
—	O
possibly	O
taking	O
two	O
streams	O
from	O
memory	O
—	O
and	O
writing	O
a	O
separate	O
stream	O
back	O
to	O
memory	O
.	O
</s>
<s>
Two	O
programming	O
languages	O
,	O
Alpha	O
and	O
Beta	B-Language
(	O
not	O
be	O
confused	O
with	O
Simula-inspired	O
BETA	B-Language
programming	I-Language
language	I-Language
)	O
were	O
designed	O
for	O
programming	O
it	O
,	O
and	O
IBM	O
provided	O
a	O
compiler	B-Language
for	O
the	O
former	O
around	O
the	O
time	O
the	O
machine	O
was	O
delivered	O
.	O
</s>
<s>
From	O
a	O
single	O
foreign	O
cipher	O
system	O
,	O
Harvest	B-Device
was	O
able	O
to	O
scan	O
over	O
seven	O
million	O
decrypts	O
for	O
any	O
occurrences	O
of	O
over	O
7,000	O
key	O
words	O
in	O
under	O
four	O
hours	O
.	O
</s>
<s>
The	O
computer	O
was	O
also	O
used	O
for	O
codebreaking	O
,	O
and	O
this	O
was	O
enhanced	O
by	O
an	O
early	O
distributed	O
networking	O
system	O
codenamed	O
Rye	O
,	O
which	O
allowed	O
remote	O
access	O
to	O
Harvest	B-Device
.	O
</s>
<s>
Harvest	B-Device
was	O
also	O
used	O
for	O
decipherment	O
of	O
solved	O
systems	O
;	O
the	O
report	O
goes	O
on	O
to	O
say	O
that	O
,	O
"	O
Decrypting	O
a	O
large	O
batch	O
of	O
messages	O
in	O
a	O
solved	O
system	O
 [ is ] 	O
also	O
being	O
routinely	O
handled	O
by	O
this	O
system	O
"	O
.	O
</s>
<s>
Harvest	B-Device
remained	O
in	O
use	O
until	O
1976	O
,	O
having	O
been	O
in	O
operation	O
at	O
the	O
NSA	O
for	O
fourteen	O
years	O
.	O
</s>
