<s>
TeraGrid	B-Operating_System
was	O
an	O
e-Science	O
grid	B-Architecture
computing	I-Architecture
infrastructure	I-Architecture
combining	O
resources	O
at	O
eleven	O
partner	O
sites	O
.	O
</s>
<s>
The	O
TeraGrid	B-Operating_System
integrated	O
high-performance	O
computers	O
,	O
data	O
resources	O
and	O
tools	O
,	O
and	O
experimental	O
facilities	O
.	O
</s>
<s>
Resources	O
included	O
more	O
than	O
a	O
petaflops	O
of	O
computing	O
capability	O
and	O
more	O
than	O
30	O
petabytes	O
of	O
online	O
and	O
archival	O
data	O
storage	O
,	O
with	O
rapid	O
access	O
and	O
retrieval	O
over	O
high-performance	O
computer	B-Architecture
network	I-Architecture
connections	O
.	O
</s>
<s>
TeraGrid	B-Operating_System
was	O
coordinated	O
through	O
the	O
Grid	O
Infrastructure	O
Group	O
(	O
GIG	O
)	O
at	O
the	O
University	O
of	O
Chicago	O
,	O
working	O
in	O
partnership	O
with	O
the	O
resource	O
provider	O
sites	O
in	O
the	O
United	O
States	O
.	O
</s>
<s>
The	O
TeraGrid	B-Operating_System
project	O
was	O
launched	O
in	O
August	O
2001	O
with	O
$53	O
million	O
in	O
funding	O
to	O
four	O
sites	O
:	O
the	O
National	B-General_Concept
Center	I-General_Concept
for	I-General_Concept
Supercomputing	I-General_Concept
Applications	I-General_Concept
(	O
NCSA	O
)	O
at	O
the	O
University	O
of	O
Illinois	O
at	O
Urbana-Champaign	O
,	O
the	O
San	O
Diego	O
Supercomputer	O
Center	O
(	O
SDSC	O
)	O
at	O
the	O
University	O
of	O
California	O
,	O
San	O
Diego	O
,	O
the	O
University	O
of	O
Chicago	O
Argonne	O
National	O
Laboratory	O
,	O
and	O
the	O
Center	O
for	O
Advanced	O
Computing	O
Research	O
(	O
CACR	O
)	O
at	O
the	O
California	O
Institute	O
of	O
Technology	O
in	O
Pasadena	O
,	O
California	O
.	O
</s>
<s>
The	O
design	O
was	O
meant	O
to	O
be	O
an	O
extensible	O
distributed	O
open	B-Operating_System
system	I-Operating_System
from	O
the	O
start	O
.	O
</s>
<s>
In	O
October	O
2002	O
,	O
the	O
Pittsburgh	O
Supercomputing	O
Center	O
(	O
PSC	O
)	O
at	O
Carnegie	O
Mellon	O
University	O
and	O
the	O
University	O
of	O
Pittsburgh	O
joined	O
the	O
TeraGrid	B-Operating_System
as	O
major	O
new	O
partners	O
when	O
NSF	O
announced	O
$35	O
million	O
in	O
supplementary	O
funding	O
.	O
</s>
<s>
The	O
TeraGrid	B-Operating_System
network	O
was	O
transformed	O
through	O
the	O
ETF	O
project	O
from	O
a	O
4-site	O
mesh	B-Architecture
to	O
a	O
dual-hub	O
backbone	B-General_Concept
network	I-General_Concept
with	O
connection	O
points	O
in	O
Los	O
Angeles	O
and	O
at	O
the	O
Starlight	O
facilities	O
in	O
Chicago	O
.	O
</s>
<s>
In	O
October	O
2003	O
,	O
NSF	O
awarded	O
$10	O
million	O
to	O
add	O
four	O
sites	O
to	O
TeraGrid	B-Operating_System
as	O
well	O
as	O
to	O
establish	O
a	O
third	O
network	O
hub	O
,	O
in	O
Atlanta	O
.	O
</s>
<s>
TeraGrid	B-Operating_System
construction	O
was	O
also	O
made	O
possible	O
through	O
corporate	O
partnerships	O
with	O
Sun	O
Microsystems	O
,	O
IBM	O
,	O
Intel	O
Corporation	O
,	O
Qwest	O
Communications	O
,	O
Juniper	O
Networks	O
,	O
Myricom	B-General_Concept
,	O
Hewlett-Packard	O
Company	O
,	O
and	O
Oracle	B-Application
Corporation	I-Application
.	O
</s>
<s>
TeraGrid	B-Operating_System
construction	O
was	O
completed	O
in	O
October	O
2004	O
,	O
at	O
which	O
time	O
the	O
TeraGrid	B-Operating_System
facility	O
began	O
full	O
production	O
.	O
</s>
<s>
Using	O
high-performance	O
network	O
connections	O
,	O
the	O
TeraGrid	B-Operating_System
featured	O
high-performance	O
computers	O
,	O
data	O
resources	O
and	O
tools	O
,	O
and	O
high-end	O
experimental	O
facilities	O
around	O
the	O
USA	O
.	O
</s>
<s>
In	O
2006	O
,	O
the	O
University	O
of	O
Michigan	O
's	O
School	O
of	O
Information	O
began	O
a	O
study	O
of	O
TeraGrid	B-Operating_System
.	O
</s>
<s>
In	O
May	O
2007	O
,	O
TeraGrid	B-Operating_System
integrated	O
resources	O
included	O
more	O
than	O
250	O
teraflops	O
of	O
computing	O
capability	O
and	O
more	O
than	O
30	O
petabytes	O
(	O
quadrillions	O
of	O
bytes	O
)	O
of	O
online	O
and	O
archival	O
data	O
storage	O
with	O
rapid	O
access	O
and	O
retrieval	O
over	O
high-performance	O
networks	O
.	O
</s>
<s>
In	O
late	O
2009	O
,	O
The	O
TeraGrid	B-Operating_System
resources	O
had	O
grown	O
to	O
2	O
petaflops	O
of	O
computing	O
capability	O
and	O
more	O
than	O
60	O
petabytes	O
storage	O
.	O
</s>
<s>
In	O
mid	O
2009	O
,	O
NSF	O
extended	O
the	O
operation	O
of	O
TeraGrid	B-Operating_System
to	O
2011	O
.	O
</s>
<s>
XSEDE	O
is	O
led	O
by	O
John	O
Towns	O
at	O
the	O
University	O
of	O
Illinois	O
's	O
National	B-General_Concept
Center	I-General_Concept
for	I-General_Concept
Supercomputing	I-General_Concept
Applications	I-General_Concept
.	O
</s>
<s>
TeraGrid	B-Operating_System
resources	O
are	O
integrated	O
through	O
a	O
service-oriented	O
architecture	O
in	O
that	O
each	O
resource	O
provides	O
a	O
"	O
service	O
"	O
that	O
is	O
defined	O
in	O
terms	O
of	O
interface	O
and	O
operation	O
.	O
</s>
<s>
Computational	O
resources	O
run	O
a	O
set	O
of	O
software	O
packages	O
called	O
"	O
Coordinated	O
TeraGrid	B-Operating_System
Software	O
and	O
Services	O
"	O
(	O
CTSS	O
)	O
.	O
</s>
<s>
CTSS	O
provides	O
a	O
familiar	O
user	O
environment	O
on	O
all	O
TeraGrid	B-Operating_System
systems	O
,	O
allowing	O
scientists	O
to	O
more	O
easily	O
port	O
code	O
from	O
one	O
system	O
to	O
another	O
.	O
</s>
<s>
TeraGrid	B-Operating_System
uses	O
a	O
10	O
Gigabits	O
per	O
second	O
dedicated	O
fiber-optical	O
backbone	B-General_Concept
network	I-General_Concept
,	O
with	O
hubs	O
in	O
Chicago	O
,	O
Denver	O
,	O
and	O
Los	O
Angeles	O
.	O
</s>
<s>
TeraGrid	B-Operating_System
users	O
primarily	O
came	O
from	O
U.S.	O
universities	O
.	O
</s>
<s>
All	O
allocation	O
proposals	O
are	O
handled	O
through	O
the	O
TeraGrid	B-Operating_System
website	O
.	O
</s>
<s>
Proposers	O
select	O
a	O
scientific	O
discipline	O
that	O
most	O
closely	O
describes	O
their	O
work	O
,	O
and	O
this	O
enables	O
reporting	O
on	O
the	O
allocation	O
of	O
,	O
and	O
use	O
of	O
,	O
TeraGrid	B-Operating_System
by	O
scientific	O
discipline	O
.	O
</s>
<s>
As	O
of	O
July	O
2006	O
the	O
scientific	O
profile	O
of	O
TeraGrid	B-Operating_System
allocations	O
and	O
usage	O
was	O
:	O
</s>
<s>
Starting	O
in	O
2006	O
,	O
TeraGrid	B-Operating_System
provided	O
application-specific	O
services	O
to	O
Science	O
Gateway	O
partners	O
,	O
who	O
serve	O
(	O
generally	O
via	O
a	O
web	O
portal	O
)	O
discipline-specific	O
scientific	O
and	O
education	O
communities	O
.	O
</s>
<s>
Through	O
the	O
Science	O
Gateways	O
program	O
TeraGrid	B-Operating_System
aims	O
to	O
broaden	O
access	O
by	O
at	O
least	O
an	O
order	O
of	O
magnitude	O
in	O
terms	O
of	O
the	O
number	O
of	O
scientists	O
,	O
students	O
,	O
and	O
educators	O
who	O
are	O
able	O
to	O
use	O
TeraGrid	B-Operating_System
.	O
</s>
