<s>
Network	B-General_Concept
Level	I-General_Concept
Authentication	I-General_Concept
(	O
NLA	O
)	O
is	O
a	O
feature	O
of	O
Remote	B-Protocol
Desktop	I-Protocol
Services	I-Protocol
(	O
RDP	O
Server	O
)	O
or	O
Remote	B-Protocol
Desktop	I-Protocol
Connection	I-Protocol
(	O
RDP	O
Client	O
)	O
that	O
requires	O
the	O
connecting	O
user	O
to	O
authenticate	O
themselves	O
before	O
a	O
session	O
is	O
established	O
with	O
the	O
server	O
.	O
</s>
<s>
Network	B-General_Concept
Level	I-General_Concept
Authentication	I-General_Concept
delegates	O
the	O
user	O
's	O
credentials	O
from	O
the	O
client	O
through	O
a	O
client-side	O
Security	B-Protocol
Support	I-Protocol
Provider	I-Protocol
and	O
prompts	O
the	O
user	O
to	O
authenticate	O
before	O
establishing	O
a	O
session	O
on	O
the	O
server	O
.	O
</s>
<s>
Network	B-General_Concept
Level	I-General_Concept
Authentication	I-General_Concept
was	O
introduced	O
in	O
RDP	O
6.0	O
and	O
supported	O
initially	O
in	O
Windows	B-Application
Vista	I-Application
.	O
</s>
<s>
It	O
uses	O
the	O
new	O
Security	B-Protocol
Support	I-Protocol
Provider	I-Protocol
,	O
CredSSP	O
,	O
which	O
is	O
available	O
through	O
SSPI	B-Protocol
in	O
Windows	B-Application
Vista	I-Application
.	O
</s>
<s>
With	O
Windows	B-Application
XP	I-Application
Service	O
Pack	O
3	O
,	O
CredSSP	O
was	O
introduced	O
on	O
that	O
platform	O
and	O
the	O
included	O
RDP	O
6.1	O
Client	O
supports	O
NLA	O
;	O
however	O
CredSSP	O
must	O
be	O
enabled	O
in	O
the	O
registry	O
first	O
.	O
</s>
<s>
The	O
advantages	O
of	O
Network	B-General_Concept
Level	I-General_Concept
Authentication	I-General_Concept
are	O
:	O
</s>
<s>
It	O
requires	O
fewer	O
remote	B-Protocol
computer	I-Protocol
resources	O
initially	O
,	O
by	O
preventing	O
the	O
initiation	O
of	O
a	O
full	O
remote	B-Protocol
desktop	I-Protocol
connection	I-Protocol
until	O
the	O
user	O
is	O
authenticated	O
,	O
reducing	O
the	O
risk	O
of	O
denial-of-service	O
attacks	O
.	O
</s>
<s>
It	O
allows	O
NT	O
Single	O
sign-on	O
(	O
SSO	O
)	O
to	O
extend	O
to	O
Remote	B-Protocol
Desktop	I-Protocol
Services	I-Protocol
.	O
</s>
<s>
To	O
use	O
Network	B-General_Concept
Level	I-General_Concept
Authentication	I-General_Concept
in	O
Remote	B-Protocol
Desktop	I-Protocol
Services	I-Protocol
,	O
the	O
client	O
must	O
be	O
running	O
Windows	B-Application
XP	I-Application
SP3	O
or	O
later	O
,	O
and	O
the	O
host	O
must	O
be	O
running	O
Windows	B-Application
Vista	I-Application
or	O
later	O
or	O
Windows	O
Server	O
2008	O
or	O
later	O
.	O
</s>
<s>
Support	O
for	O
RDP	O
Servers	O
requiring	O
Network	B-General_Concept
Level	I-General_Concept
Authentication	I-General_Concept
needs	O
to	O
be	O
configured	O
via	O
registry	O
keys	O
for	O
use	O
on	O
Windows	B-Application
XP	I-Application
SP3	O
.	O
</s>
