<s>
rdesktop	B-Protocol
is	O
an	O
implementation	O
of	O
a	O
client	O
software	O
for	O
Microsoft	O
's	O
proprietary	O
Remote	B-Protocol
Desktop	I-Protocol
Protocol	I-Protocol
(	O
RDP	O
)	O
.	O
</s>
<s>
Rdesktop	B-Protocol
is	O
free	B-License
and	I-License
open-source	I-License
software	I-License
,	O
subject	O
to	O
the	O
requirements	O
of	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
(	O
GPL-3.0-or-later	B-License
)	O
,	O
and	O
is	O
available	O
for	O
Linux	B-Application
and	O
BSD	B-Operating_System
as	O
well	O
as	O
for	O
Microsoft	B-Application
Windows	I-Application
.	O
</s>
<s>
As	O
of	O
August	O
2013	O
,	O
rdesktop	B-Protocol
implements	O
a	O
large	O
subset	O
of	O
the	O
RDP	O
5	O
protocol	O
.	O
</s>
<s>
Unlike	O
Remote	B-Protocol
Desktop	I-Protocol
Connection	I-Protocol
in	O
modern	O
versions	O
of	O
Windows	O
,	O
rdesktop	B-Protocol
still	O
supports	O
the	O
older	O
RDP	O
4.0	O
protocol	O
used	O
by	O
Windows	B-Device
NT	I-Device
4.0	I-Device
Terminal	O
Server	O
Edition	O
and	O
Windows	O
2000	O
Server	O
.	O
</s>
<s>
Support	O
for	O
the	O
additional	O
features	O
available	O
in	O
RDP	O
5.1	O
and	O
RDP	O
6	O
(	O
including	O
multi-head	B-General_Concept
display	I-General_Concept
spanning	O
,	O
window	B-Operating_System
composition	I-Operating_System
and	O
console	O
connection	O
)	O
have	O
not	O
yet	O
been	O
implemented	O
,	O
although	O
some	O
have	O
been	O
officially	O
documented	O
on	O
MSDN	O
.	O
</s>
<s>
Rdesktop	B-Protocol
is	O
commonly	O
used	O
on	O
desktop	O
ReactOS	B-Application
and	O
Linux	B-Application
installations	O
to	O
connect	O
to	O
Microsoft	B-Application
Windows	I-Application
running	O
Remote	B-Protocol
Desktop	I-Protocol
Services	I-Protocol
.	O
</s>
<s>
There	O
are	O
many	O
GUI	O
clients	O
,	O
like	O
tsclient	B-Language
,	O
Gnome-RDP	O
and	O
KDE	O
Remote	B-Protocol
Desktop	I-Protocol
Connection	I-Protocol
(	O
KRDC	B-Language
)	O
,	O
which	O
are	O
graphical	O
front-ends	O
to	O
rdesktop	B-Protocol
.	O
</s>
<s>
The	O
program	O
has	O
also	O
been	O
integrated	O
into	O
several	O
thin	B-Device
client	I-Device
Linux	B-Application
distributions	O
like	O
Thinstation	O
and	O
the	O
PC	O
TSC	O
project	O
,	O
as	O
well	O
as	O
some	O
thin	B-Device
client	I-Device
appliances	O
.	O
</s>
