<s>
A	O
remote	B-Device
access	I-Device
service	I-Device
(	O
RAS	O
)	O
is	O
any	O
combination	O
of	O
hardware	O
and	O
software	O
to	O
enable	O
the	O
remote	B-Protocol
access	I-Protocol
tools	I-Protocol
or	O
information	O
that	O
typically	O
reside	O
on	O
a	O
network	B-Architecture
of	O
IT	O
devices	O
.	O
</s>
<s>
A	O
remote	B-Device
access	I-Device
service	I-Device
connects	O
a	O
client	B-Protocol
to	O
a	O
host	O
computer	O
,	O
known	O
as	O
a	O
remote	B-Device
access	I-Device
server	I-Device
.	O
</s>
<s>
The	O
most	O
common	O
approach	O
to	O
this	O
service	O
is	O
remote	O
control	O
of	O
a	O
computer	O
by	O
using	O
another	O
device	O
which	O
needs	O
internet	O
or	O
any	O
other	O
network	B-Architecture
connection	O
.	O
</s>
<s>
Therefore	O
you	O
can	O
find	O
various	O
professional	O
first-party	O
,	O
third-party	O
,	O
open	O
source	O
,	O
and	O
freeware	O
remote	B-Protocol
desktop	I-Protocol
applications	O
.	O
</s>
<s>
Which	O
some	O
of	O
those	O
are	O
cross-platform	O
across	O
various	O
versions	O
of	O
Windows	B-Application
,	O
macOS	O
,	O
UNIX	B-Application
,	O
and	O
Linux	O
.	O
</s>
<s>
Remote	B-Protocol
desktop	I-Protocol
programs	O
may	O
include	O
LogMeIn	O
or	O
TeamViewer	O
.	O
</s>
<s>
To	O
use	O
RAS	O
from	O
a	O
remote	O
node	O
,	O
a	O
RAS	O
client	B-Protocol
program	I-Protocol
is	O
needed	O
,	O
or	O
any	O
PPP	B-Protocol
client	B-Protocol
software	I-Protocol
.	O
</s>
<s>
Most	O
remote	B-Protocol
control	I-Protocol
programs	I-Protocol
work	O
with	O
RAS	O
.	O
</s>
<s>
PPP	B-Protocol
is	O
a	O
set	O
of	O
industry	O
standard	O
framing	O
and	O
authentication	O
protocols	O
that	O
enable	O
remote	B-Protocol
access	I-Protocol
.	O
</s>
<s>
Microsoft	O
Remote	B-Device
Access	I-Device
Server	I-Device
(	O
RAS	O
)	O
is	O
the	O
predecessor	O
to	O
Microsoft	O
Routing	O
and	O
Remote	B-Device
Access	I-Device
Server	I-Device
(	O
RRAS	O
)	O
.	O
</s>
<s>
RRAS	O
is	O
a	O
Microsoft	B-Application
Windows	I-Application
Server	O
feature	O
that	O
allows	O
Microsoft	B-Application
Windows	I-Application
clients	O
to	O
remotely	O
access	O
a	O
Microsoft	B-Application
Windows	I-Application
network	B-Architecture
.	O
</s>
<s>
The	O
term	O
was	O
originally	O
coined	O
by	O
Microsoft	O
when	O
referring	O
to	O
their	O
built-in	O
Windows	B-Device
NT	I-Device
remote	B-Protocol
access	I-Protocol
tools	I-Protocol
.	O
</s>
<s>
RAS	O
is	O
a	O
service	O
provided	O
by	O
Windows	B-Device
NT	I-Device
which	O
allows	O
most	O
of	O
the	O
services	O
which	O
would	O
be	O
available	O
on	O
a	O
network	B-Architecture
to	O
be	O
accessed	O
over	O
a	O
modem	B-Application
link	O
.	O
</s>
<s>
The	O
service	O
includes	O
support	O
for	O
dialup	O
and	O
logon	B-General_Concept
,	O
presents	O
the	O
same	O
network	B-Architecture
interface	O
as	O
the	O
normal	O
network	B-Architecture
drivers	O
(	O
albeit	O
slightly	O
slower	O
)	O
.	O
</s>
<s>
RAS	O
works	O
with	O
several	O
major	O
network	B-Architecture
protocols	O
,	O
including	O
TCP/IP	B-Protocol
,	O
IPX	B-Protocol
,	O
and	O
NBF	B-Protocol
.	O
</s>
<s>
It	O
is	O
not	O
necessary	O
to	O
run	O
Windows	B-Device
NT	I-Device
on	O
the	O
client	B-Protocol
—	O
there	O
are	O
client	B-Protocol
versions	O
for	O
other	O
Windows	B-Application
operating	I-Application
systems	I-Application
.	O
</s>
<s>
RAS	O
enables	O
users	O
to	O
log	O
into	O
an	O
NT-based	B-Device
LAN	B-General_Concept
using	O
a	O
modem	B-Application
,	O
X.25	B-Protocol
connection	O
or	O
WAN	O
link	O
.	O
</s>
<s>
Starting	O
in	O
the	O
mid-1990s	O
,	O
several	O
manufacturers	O
such	O
as	O
U.S.	O
Robotics	O
produced	O
"	O
modem	B-Application
terminal	O
servers	O
"	O
.	O
</s>
<s>
Instead	O
of	O
having	O
RS-232	O
ports	O
,	O
these	O
would	O
directly	O
incorporate	O
an	O
analog	B-Application
modem	I-Application
.	O
</s>
<s>
Modern	O
versions	O
interface	O
to	O
an	O
ISDN	B-Protocol
PRI	I-Protocol
instead	O
of	O
having	O
analog	B-Application
modem	I-Application
ports	O
.	O
</s>
<s>
Remote	B-Device
access	I-Device
services	I-Device
are	O
now	O
commonly	O
used	O
for	O
online	O
technical	O
support	O
for	O
personal	O
computers	O
.	O
</s>
<s>
This	O
used	O
the	O
MS-DOS	B-Application
based	O
program	O
called	O
PC	B-Protocol
Anywhere	I-Protocol
to	O
directly	O
link	O
into	O
MS-DOS	B-Application
and	O
early	O
Windows-based	O
PCs	O
.	O
</s>
<s>
The	O
company	O
had	O
been	O
providing	O
RAS	O
support	O
for	O
Unix	B-Application
based	O
corporate	O
systems	O
since	O
1985	O
.	O
</s>
