<s>
The	O
Cray	B-Device
MTA-2	I-Device
is	O
a	O
shared-memory	O
MIMD	B-Operating_System
computer	O
marketed	O
by	O
Cray	O
Inc	O
.	O
</s>
<s>
It	O
is	O
an	O
unusual	O
design	O
based	O
on	O
the	O
Tera	B-Architecture
computer	I-Architecture
designed	O
by	O
Tera	B-Architecture
Computer	I-Architecture
Company	I-Architecture
.	O
</s>
<s>
The	O
original	O
Tera	B-Architecture
computer	I-Architecture
(	O
also	O
known	O
as	O
the	O
MTA	O
)	O
turned	O
out	O
to	O
be	O
nearly	O
unmanufacturable	O
due	O
to	O
its	O
aggressive	O
packaging	O
and	O
circuit	O
technology	O
.	O
</s>
<s>
The	O
MTA-2	B-Device
was	O
an	O
attempt	O
to	O
correct	O
these	O
problems	O
while	O
maintaining	O
essentially	O
the	O
same	O
processor	O
architecture	O
respun	O
in	O
one	O
silicon	O
ASIC	O
,	O
down	O
from	O
some	O
26	O
gallium	O
arsenide	O
ASICs	O
in	O
the	O
original	O
MTA	O
;	O
and	O
while	O
regressing	O
the	O
network	O
design	O
from	O
a	O
4-D	O
torus	O
topology	O
to	O
a	O
less	O
efficient	O
but	O
more	O
scalable	O
Cayley	O
graph	O
topology	O
.	O
</s>
<s>
The	O
name	O
Cray	O
was	O
added	O
to	O
the	O
second	O
version	O
after	O
Tera	B-Architecture
Computer	I-Architecture
Company	I-Architecture
bought	O
the	O
remains	O
of	O
the	O
Cray	O
Research	O
division	O
of	O
Silicon	O
Graphics	O
in	O
2000	O
and	O
renamed	O
itself	O
Cray	O
Inc	O
.	O
</s>
<s>
The	O
MTA-2	B-Device
was	O
not	O
a	O
commercial	O
success	O
,	O
with	O
only	O
one	O
moderately-sized	O
40-processor	O
system	O
(	O
"	O
Boomer	O
"	O
)	O
being	O
sold	O
to	O
the	O
United	O
States	O
Naval	O
Research	O
Laboratory	O
in	O
2002	O
,	O
and	O
one	O
4-processor	O
system	O
sold	O
to	O
the	O
Electronic	O
Navigation	O
Research	O
Institute	O
(	O
ENRI	O
)	O
in	O
Japan	O
.	O
</s>
