<s>
AuthIP	B-Protocol
is	O
a	O
Microsoft	O
proprietary	O
extension	O
of	O
the	O
IKE	B-Protocol
cryptographic	B-Protocol
protocol	I-Protocol
.	O
</s>
<s>
AuthIP	B-Protocol
is	O
supported	O
in	O
Windows	B-Application
Vista	I-Application
and	O
later	O
on	O
the	O
client	O
and	O
Windows	B-Device
Server	I-Device
2008	I-Device
and	O
later	O
on	O
the	O
server	O
.	O
</s>
<s>
AuthIP	B-Protocol
adds	O
a	O
second	O
authentication	O
to	O
the	O
standard	O
IKE	B-Protocol
authentication	O
which	O
,	O
according	O
to	O
Microsoft	O
,	O
increases	O
security	O
and	O
deployability	O
of	O
IPsec	B-Protocol
VPNs	B-Application
.	O
</s>
<s>
AuthIP	B-Protocol
adds	O
support	O
for	O
user-based	O
authentication	O
by	O
using	O
Kerberos	O
v5	O
or	O
SSL	O
certificates	O
.	O
</s>
<s>
AuthIP	B-Protocol
is	O
not	O
compatible	O
with	O
IKEv2	B-Protocol
,	O
an	O
IETF	O
standard	O
with	O
similar	O
characteristics	O
;	O
however	O
Windows	B-Device
7	I-Device
and	O
Windows	B-Device
Server	I-Device
2008	I-Device
R2	I-Device
also	O
support	O
IKEv2	B-Protocol
.	O
</s>
