<s>
GSS-TSIG	B-Protocol
(	O
Generic	B-Protocol
Security	I-Protocol
Service	I-Protocol
Algorithm	I-Protocol
for	I-Protocol
Secret	I-Protocol
Key	I-Protocol
Transaction	I-Protocol
)	O
is	O
an	O
extension	O
to	O
the	O
TSIG	B-Protocol
DNS	O
authentication	B-Protocol
protocol	I-Protocol
for	O
secure	O
key	O
exchange	O
.	O
</s>
<s>
It	O
is	O
a	O
GSS-API	O
algorithm	O
which	O
uses	O
Kerberos	B-Protocol
for	O
passing	O
security	O
tokens	O
to	O
provide	O
authentication	O
,	O
integrity	O
and	O
confidentiality	O
.	O
</s>
<s>
GSS-TSIG	B-Protocol
(	O
RFC	O
3645	O
)	O
uses	O
a	O
mechanism	O
like	O
SPNEGO	B-Protocol
with	O
Kerberos	B-Protocol
or	O
NTLM	O
.	O
</s>
<s>
GSS-TSIG	B-Protocol
uses	O
TKEY	B-Protocol
records	I-Protocol
for	O
key	O
exchange	O
between	O
the	O
DNS	O
client	O
and	O
server	O
in	O
GSS-TSIG	B-Protocol
mode	O
.	O
</s>
<s>
For	O
authentication	O
between	O
the	O
DNS	O
client	O
and	O
Active	B-Protocol
Directory	I-Protocol
,	O
the	O
AS-REQ	O
,	O
AS-REP	O
,	O
TGS-REQ	O
,	O
TGS-REP	O
exchanges	O
must	O
take	O
place	O
for	O
granting	O
of	O
ticket	O
and	O
establishing	O
a	O
security	O
context	O
.	O
</s>
