<s>
CAVE-based	B-Protocol
Authentication	I-Protocol
(	O
a.k.a.	O
</s>
<s>
There	O
are	O
two	O
network	O
entities	O
involved	O
in	O
CAVE-based	B-Protocol
authentication	I-Protocol
when	O
roaming	O
:	O
</s>
<s>
In	O
either	O
case	O
,	O
CAVE-based	B-Protocol
authentication	I-Protocol
is	O
based	O
on	O
the	O
CAVE	O
algorithm	O
and	O
the	O
following	O
two	O
shared	O
keys	O
:	O
</s>
<s>
CAVE-based	B-Protocol
authentication	I-Protocol
is	O
a	O
one-way	O
authentication	O
mechanism	O
that	O
always	O
involves	O
the	O
network	O
authenticating	O
the	O
MS	O
(	O
with	O
the	O
exception	O
of	O
the	O
base	O
station	O
challenge	O
procedure	O
that	O
occurs	O
only	O
during	O
an	O
SSD	O
update	O
)	O
.	O
</s>
<s>
CAVE-based	B-Protocol
authentication	I-Protocol
procedures	O
are	O
specified	O
in	O
TIA-41	O
(	O
3GPP2	O
X.S0004	O
)	O
.	O
</s>
