<s>
Authentication	B-Protocol
and	I-Protocol
Key	I-Protocol
Agreement	I-Protocol
(	O
AKA	B-Protocol
)	O
is	O
a	O
security	B-Protocol
protocol	I-Protocol
used	O
in	O
3G	B-Architecture
networks	I-Architecture
.	O
</s>
<s>
AKA	B-Protocol
is	O
also	O
used	O
for	O
one-time	O
password	O
generation	O
mechanism	O
for	O
digest	B-Protocol
access	I-Protocol
authentication	I-Protocol
.	O
</s>
<s>
AKA	B-Protocol
is	O
a	O
challenge	O
–	O
response	O
based	O
mechanism	O
that	O
uses	O
symmetric	B-Algorithm
cryptography	I-Algorithm
.	O
</s>
<s>
AKA	B-Protocol
–	O
Authentication	B-Protocol
and	I-Protocol
Key	I-Protocol
Agreement	I-Protocol
a.k.a.	O
</s>
<s>
3G	B-Architecture
Authentication	O
,	O
Enhanced	O
Subscriber	O
Authorization	O
(	O
ESA	O
)	O
.	O
</s>
<s>
The	O
basis	O
for	O
the	O
3G	B-Architecture
authentication	O
mechanism	O
,	O
defined	O
as	O
a	O
successor	O
to	O
CAVE-based	B-Protocol
authentication	I-Protocol
,	O
AKA	B-Protocol
provides	O
procedures	O
for	O
mutual	O
authentication	O
of	O
the	O
Mobile	O
Station	O
(	O
MS	B-Protocol
)	O
and	O
serving	O
system	O
.	O
</s>
<s>
The	O
successful	O
execution	O
of	O
AKA	B-Protocol
results	O
in	O
the	O
establishment	O
of	O
a	O
security	O
association	O
(	O
i.e.	O
,	O
set	O
of	O
security	O
data	O
)	O
between	O
the	O
MS	B-Protocol
and	O
serving	O
system	O
that	O
enables	O
a	O
set	O
of	O
security	O
services	O
to	O
be	O
provided	O
.	O
</s>
<s>
Major	O
advantages	O
of	O
AKA	B-Protocol
over	O
CAVE-based	B-Protocol
authentication	I-Protocol
include	O
:	O
</s>
<s>
AKA	B-Protocol
is	O
not	O
yet	O
implemented	O
in	O
CDMA2000	O
networks	O
,	O
although	O
it	O
is	O
expected	O
to	O
be	O
used	O
for	O
IMS	B-Protocol
.	O
</s>
<s>
To	O
ensure	O
interoperability	O
with	O
current	O
devices	O
and	O
partner	O
networks	O
,	O
support	O
for	O
AKA	B-Protocol
in	O
CDMA	O
networks	O
and	O
handsets	O
will	O
likely	O
be	O
in	O
addition	O
to	O
CAVE-based	B-Protocol
authentication	I-Protocol
.	O
</s>
<s>
Air	O
interface	O
support	O
for	O
AKA	B-Protocol
is	O
included	O
in	O
all	O
releases	O
following	O
CDMA2000	O
Rev	O
C	O
.	O
</s>
<s>
TIA-41	O
MAP	O
support	O
for	O
AKA	B-Protocol
was	O
defined	O
in	O
TIA-945	O
(	O
3GPP2	O
X.S0006	O
)	O
,	O
which	O
has	O
been	O
integrated	O
into	O
TIA-41	O
(	O
3GPP2	O
X.S0004	O
)	O
.	O
</s>
<s>
For	O
information	O
on	O
AKA	B-Protocol
in	O
roaming	O
,	O
see	O
CDG	O
Reference	O
Document	O
#138	O
.	O
</s>
<s>
AKA	B-Protocol
a	O
mechanism	O
which	O
performs	O
authentication	O
and	O
session	O
key	O
distribution	O
in	O
Universal	B-Protocol
Mobile	I-Protocol
Telecommunications	I-Protocol
System	I-Protocol
(	O
UMTS	B-Protocol
)	O
networks	O
.	O
</s>
<s>
AKA	B-Protocol
is	O
a	O
challenge	O
–	O
response	O
based	O
mechanism	O
that	O
uses	O
symmetric	B-Algorithm
cryptography	I-Algorithm
.	O
</s>
<s>
AKA	B-Protocol
is	O
typically	O
run	O
in	O
a	O
UMTS	B-Protocol
IP	O
Multimedia	O
Services	O
Identity	O
Module	O
(	O
ISIM	O
)	O
,	O
which	O
is	O
an	O
application	O
on	O
a	O
UICC	B-Algorithm
(	O
Universal	B-Algorithm
Integrated	I-Algorithm
Circuit	I-Algorithm
Card	I-Algorithm
)	O
.	O
</s>
<s>
AKA	B-Protocol
is	O
defined	O
in	O
RFC	O
3310	O
.	O
</s>
<s>
An	O
attack	O
against	O
all	O
variants	O
of	O
AKA	B-Protocol
has	O
been	O
reported	O
,	O
including	O
5G	O
.	O
</s>
