<s>
EAX	B-Algorithm
mode	I-Algorithm
(	O
encrypt-then-authenticate-then-translate	O
)	O
is	O
a	O
mode	B-Algorithm
of	I-Algorithm
operation	I-Algorithm
for	O
cryptographic	O
block	O
ciphers	O
.	O
</s>
<s>
It	O
is	O
an	O
Authenticated	B-Algorithm
Encryption	I-Algorithm
with	O
Associated	O
Data	O
(	O
AEAD	O
)	O
algorithm	O
designed	O
to	O
simultaneously	O
provide	O
both	O
authentication	O
and	O
privacy	O
of	O
the	O
message	O
(	O
authenticated	B-Algorithm
encryption	I-Algorithm
)	O
with	O
a	O
two-pass	O
scheme	O
,	O
one	O
pass	O
for	O
achieving	O
privacy	O
and	O
one	O
for	O
authenticity	O
for	O
each	O
block	O
.	O
</s>
<s>
EAX	B-Algorithm
mode	I-Algorithm
was	O
submitted	O
on	O
October	O
3	O
,	O
2003	O
to	O
the	O
attention	O
of	O
NIST	O
in	O
order	O
to	O
replace	O
CCM	B-Algorithm
as	O
standard	O
AEAD	O
mode	B-Algorithm
of	I-Algorithm
operation	I-Algorithm
,	O
since	O
CCM	B-Algorithm
mode	I-Algorithm
lacks	O
some	O
desirable	O
attributes	O
of	O
EAX	O
and	O
is	O
more	O
complex	O
.	O
</s>
<s>
The	O
reference	O
implementation	O
in	O
the	O
aforementioned	O
paper	O
uses	O
AES	O
in	O
CTR	O
mode	O
for	O
encryption	O
combined	O
with	O
AES	O
OMAC	B-Algorithm
for	O
authentication	O
.	O
</s>
<s>
Being	O
a	O
two-pass	O
scheme	O
,	O
EAX	B-Algorithm
mode	I-Algorithm
is	O
slower	O
than	O
a	O
well	O
designed	O
one-pass	O
scheme	O
based	O
on	O
the	O
same	O
primitives	O
.	O
</s>
<s>
EAX	B-Algorithm
mode	I-Algorithm
has	O
several	O
desirable	O
attributes	O
,	O
notably	O
:	O
</s>
<s>
Notably	O
,	O
CCM	B-Algorithm
mode	I-Algorithm
lacks	O
the	O
last	O
2	O
attributes	O
(	O
CCM	B-Algorithm
can	O
process	O
Associated	O
Data	O
,	O
it	O
ca	O
n't	O
pre-process	O
it	O
)	O
.	O
</s>
<s>
The	O
authors	O
of	O
EAX	B-Algorithm
mode	I-Algorithm
,	O
Mihir	O
Bellare	O
,	O
Phillip	O
Rogaway	O
,	O
and	O
David	O
Wagner	O
placed	O
the	O
work	O
under	O
public	O
domain	O
and	O
have	O
stated	O
that	O
they	O
were	O
unaware	O
of	O
any	O
patents	O
covering	O
this	O
technology	O
.	O
</s>
<s>
Thus	O
,	O
EAX	B-Algorithm
mode	I-Algorithm
of	O
operation	O
is	O
believed	O
to	O
be	O
free	O
and	O
unencumbered	O
for	O
any	O
use	O
.	O
</s>
<s>
A	O
modification	O
of	O
the	O
EAX	B-Algorithm
mode	I-Algorithm
,	O
so	O
called	O
EAX′	O
or	O
EAXprime	O
,	O
is	O
used	O
in	O
the	O
ANSI	O
C12.22	O
standard	O
for	O
transport	O
of	O
meter-based	O
data	O
over	O
a	O
network	O
.	O
</s>
