<s>
Linux	B-Application
Terminal	I-Application
Server	I-Application
Project	I-Application
(	O
LTSP	O
)	O
is	O
a	O
free	B-Application
and	I-Application
open	I-Application
source	I-Application
terminal	B-Device
server	I-Device
for	O
Linux	B-Application
that	O
allows	O
many	O
people	O
to	O
simultaneously	O
use	O
the	O
same	O
computer	O
.	O
</s>
<s>
Applications	O
run	O
on	O
the	O
server	O
with	O
a	O
terminal	O
known	O
as	O
a	O
thin	B-Device
client	I-Device
(	O
also	O
known	O
as	O
an	O
X	B-Protocol
terminal	I-Protocol
)	O
handling	O
input	O
and	O
output	O
.	O
</s>
<s>
Improving	O
access	O
to	O
computers	O
becomes	O
less	O
costly	O
as	O
thin	B-Device
client	I-Device
machines	O
can	O
be	O
older	O
computers	O
that	O
are	O
no	O
longer	O
suitable	O
for	O
running	O
a	O
full	O
desktop	O
OS	O
.	O
</s>
<s>
Even	O
a	O
relatively	O
slow	O
CPU	O
with	O
as	O
little	O
as	O
128MB	O
of	O
RAM	O
can	O
deliver	O
excellent	O
performance	O
as	O
a	O
thin	B-Device
client	I-Device
.	O
</s>
<s>
By	O
converting	O
existing	O
computers	O
into	O
thin	B-Device
clients	I-Device
,	O
an	O
educational	O
institution	O
can	O
also	O
gain	O
more	O
control	O
over	O
how	O
their	O
students	O
are	O
using	O
computing	O
resources	O
as	O
all	O
of	O
the	O
user	O
sessions	O
can	O
be	O
monitored	O
on	O
the	O
server	O
.	O
</s>
<s>
The	O
founder	O
and	O
project	O
leader	O
of	O
LTSP	O
is	O
Jim	B-Application
McQuillan	I-Application
,	O
and	O
LTSP	O
is	O
distributed	O
under	O
the	O
terms	O
of	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
<s>
On	O
the	O
LTSP	O
server	O
,	O
a	O
chroot	B-Application
environment	I-Application
is	O
set	O
up	O
with	O
a	O
minimal	O
Linux	B-Application
operating	I-Application
system	I-Application
and	O
X	B-Operating_System
environment	I-Operating_System
.	O
</s>
<s>
the	O
thin	B-Device
client	I-Device
will	O
use	O
PXE	B-Device
or	O
Network	B-Device
booting	I-Device
,	O
a	O
part	O
of	O
the	O
onboard	O
Ethernet	O
firmware	O
,	O
to	O
request	O
an	O
IP	O
address	O
and	O
boot	B-Operating_System
server	O
(	O
the	O
LTSP	O
server	O
)	O
using	O
the	O
DHCP	B-Protocol
protocol	O
.	O
</s>
<s>
A	O
PXE	B-Device
bootloader	O
(	O
PXElinux	O
)	O
is	O
loaded	O
which	O
then	O
retrieves	O
a	O
Linux	B-Application
kernel	B-Operating_System
and	O
initrd	B-Application
from	O
a	O
Trivial	B-Device
File	I-Device
Transfer	I-Device
Protocol	I-Device
(	O
TFTP	B-Device
)	O
service	O
usually	O
running	O
on	O
the	O
LTSP	O
server	O
.	O
</s>
<s>
Using	O
the	O
utilities	O
in	O
the	O
initrd	B-Application
,	O
the	O
kernel	B-Operating_System
will	O
request	O
a	O
(	O
new	O
)	O
DHCP	B-Protocol
IP	O
address	O
and	O
the	O
address	O
of	O
a	O
server	O
from	O
which	O
it	O
can	O
mount	O
its	O
root	O
filesystem	O
(	O
the	O
chroot	B-Application
mentioned	O
above	O
)	O
.	O
</s>
<s>
When	O
this	O
information	O
is	O
retrieved	O
,	O
the	O
client	O
mounts	B-Application
the	O
path	O
on	O
its	O
root	O
filesystem	O
via	O
either	O
the	O
Network	B-Protocol
File	I-Protocol
System	I-Protocol
(	O
NFS	O
)	O
or	O
Network	B-Application
Block	I-Application
Device	I-Application
(	O
NBD	O
)	O
services	O
running	O
on	O
the	O
LTSP	O
server	O
.	O
</s>
<s>
The	O
client	O
then	O
loads	O
Linux	B-Application
from	O
the	O
NFS	O
mounted	O
root	O
filesystem	O
(	O
or	O
NBD	O
filesystem	O
image	O
)	O
and	O
starts	O
the	O
X	B-Operating_System
Window	I-Operating_System
system	I-Operating_System
.	O
</s>
<s>
In	O
case	O
of	O
the	O
newer	O
MueKow	B-Application
(	O
LTSP	O
v5.x	O
)	O
setup	O
,	O
the	O
client	O
first	O
builds	O
an	O
SSH	B-Protocol
tunnel	B-Protocol
to	O
the	O
LTSP	O
server	O
's	O
X	B-Operating_System
environment	I-Operating_System
,	O
through	O
which	O
it	O
will	O
start	O
the	O
LDM	O
(	O
LTSP	O
Display	B-Device
Manager	I-Device
)	O
login	O
manager	O
locally	O
.	O
</s>
<s>
Initially	O
,	O
the	O
MILLE-Xterm	O
project	O
,	O
funded	O
by	O
Canadian	O
public	O
agencies	O
and	O
school	O
districts	O
in	O
the	O
province	O
of	O
Quebec	O
,	O
created	O
a	O
version	O
of	O
LTSP	O
integrating	O
four	O
subprojects	O
:	O
a	O
portal	O
(	O
based	O
on	O
uportal	O
)	O
,	O
an	O
open-source	O
middleware	O
stack	O
,	O
a	O
CD	O
with	O
free	B-Application
software	I-Application
for	O
Windows/Mac	O
and	O
,	O
finally	O
,	O
MILLE-Xterm	O
itself	O
.	O
</s>
<s>
The	O
MILLE-Xterm	O
project	O
's	O
goal	O
was	O
to	O
provide	O
a	O
scalable	O
infrastructure	O
for	O
massive	O
X-Terminal	O
deployment	O
.	O
</s>
<s>
MILLE	O
means	O
Modèle	O
d'Infrastructure	O
Logiciel	O
Libre	O
en	O
Éducation	O
(	O
Free	B-Application
Software	I-Application
Infrastructure	O
Model	O
for	O
Education	O
)	O
and	O
is	O
targeted	O
at	O
educational	O
institutions	O
.	O
</s>
<s>
One	O
of	O
the	O
main	O
differences	O
between	O
LTSP	O
and	O
LTSP-cluster	O
is	O
the	O
integration	O
of	O
a	O
web-based	O
central	O
control	O
center	O
that	O
replaces	O
the	O
traditional	O
"	O
one	O
configuration	O
file	O
per	O
thin	B-Device
client	I-Device
"	O
as	O
is	O
the	O
method	O
of	O
client	O
customization	O
through	O
LTSP	O
's	O
lts.conf	O
file	O
in	O
the	O
main	O
LTSP	O
.	O
</s>
<s>
LTSP-cluster	O
allows	O
organizations	O
to	O
centrally	O
manage	O
thousands	O
of	O
thin	B-Device
clients	I-Device
and	O
their	O
parameters	O
from	O
a	O
central	O
location	O
.	O
</s>
<s>
In	O
LTSP-cluster	O
high-availability	O
and	O
high-performance	O
thin-clients	B-Device
are	O
specified	O
through	O
the	O
optional	O
use	O
of	O
redundant	O
components	O
.	O
</s>
<s>
LTSP-Cluster	O
can	O
support	O
Linux	B-Application
application	O
servers	O
as	O
well	O
as	O
Windows	O
application	O
servers	O
and	O
provides	O
a	O
similar	O
level	O
of	O
support	O
,	O
centralized	O
management	O
,	O
high-availability	O
,	O
and	O
load-balancing	O
features	O
for	O
both	O
platforms	O
.	O
</s>
<s>
Also	O
included	O
is	O
support	O
for	O
virtual	O
desktops	O
for	O
remote	O
users	O
using	O
NX	B-Application
technology	I-Application
.	O
</s>
<s>
The	O
NX	B-Application
protocol	O
can	O
allow	O
remote	O
Windows	O
and	O
Linux	B-Application
sessions	O
to	O
be	O
accessed	O
from	O
a	O
web	O
browser	O
with	O
very	O
low	O
bandwidth	O
(	O
40	O
kbit/s	O
)	O
requirements	O
and	O
tolerance	O
for	O
high-latency	O
connections	O
.	O
</s>
<s>
The	O
NX	B-Application
client	I-Application
runs	O
on	O
various	O
operating	O
systems	O
including	O
Linux	B-Application
,	O
Mac	O
,	O
and	O
Windows	O
.	O
</s>
<s>
LTSP	O
v5.x	O
added	O
support	O
for	O
a	O
thin	B-Device
client	I-Device
type	O
known	O
as	O
"	O
fat	O
clients	O
"	O
.	O
</s>
<s>
With	O
the	O
advent	O
of	O
inexpensive	O
,	O
relatively	O
powerful	O
computer	O
hardware	O
,	O
the	O
idea	O
to	O
run	O
applications	O
locally	O
on	O
the	O
thin	B-Device
client	I-Device
while	O
offering	O
the	O
manageability	O
of	O
a	O
thin	B-Device
client	I-Device
solution	O
became	O
a	O
reality	O
.	O
</s>
<s>
In	O
the	O
case	O
of	O
a	O
LTSP	O
fat	O
client	O
,	O
the	O
root	O
filesystem	O
is	O
not	O
a	O
rudimentary	O
chroot	B-Application
but	O
a	O
full	O
Linux	B-Application
installation	O
as	O
a	O
chroot	B-Application
.	O
</s>
<s>
The	O
fat	O
client	O
uses	O
LDM	O
to	O
authenticate	O
to	O
the	O
LTSP	O
server	O
and	O
mounts	B-Application
user	O
home	O
directories	O
using	O
SSH	B-Protocol
and	O
FUSE	B-Application
.	O
</s>
<s>
On	O
the	O
Windows	O
platform	O
,	O
the	O
closest	O
equivalent	O
solution	O
is	O
to	O
use	O
a	O
technology	O
like	O
Intel	B-Architecture
vPro	I-Architecture
to	O
run	O
a	O
client-side	O
hypervisor	O
and	O
mount	O
the	O
root	O
filesystem	O
image	O
using	O
iSCSI	B-Protocol
.	O
</s>
