<s>
JH	B-Algorithm
is	O
a	O
cryptographic	B-Algorithm
hash	I-Algorithm
function	I-Algorithm
submitted	O
to	O
the	O
NIST	B-Algorithm
hash	I-Algorithm
function	I-Algorithm
competition	I-Algorithm
by	O
Hongjun	O
Wu	O
.	O
</s>
<s>
Though	O
chosen	O
as	O
one	O
of	O
the	O
five	O
finalists	O
of	O
the	O
competition	O
,	O
in	O
2012	O
JH	B-Algorithm
ultimately	O
lost	O
to	O
NIST	O
hash	B-Algorithm
candidate	O
Keccak	B-Algorithm
.	O
</s>
<s>
JH	B-Algorithm
has	O
a	O
1024-bit	O
state	O
,	O
and	O
works	O
on	O
512-bit	O
input	O
blocks	O
.	O
</s>
<s>
Break	O
the	O
input	O
into	O
256	O
4-bit	O
blocks	O
,	O
and	O
map	O
each	O
through	O
one	O
of	O
two	O
4-bit	O
S-boxes	B-Algorithm
,	O
the	O
choice	O
being	O
made	O
by	O
a	O
256-bit	O
round-dependent	O
key	O
schedule	O
.	O
</s>
<s>
Equivalently	O
,	O
combine	O
each	O
input	O
block	O
with	O
a	O
key	O
bit	O
,	O
and	O
map	O
the	O
result	O
through	O
a	O
5	O
→	O
4	O
bit	O
S-box	B-Algorithm
.	O
</s>
<s>
It	O
is	O
well	O
suited	O
to	O
a	O
bit	B-General_Concept
slicing	I-General_Concept
implementation	O
using	O
the	O
SSE2	B-General_Concept
instruction	O
set	O
,	O
giving	O
speeds	O
of	O
16.8	O
cycles	O
per	O
byte	O
.	O
</s>
<s>
Hash	B-Algorithm
values	O
of	O
empty	O
string	O
.	O
</s>
<s>
Even	O
a	O
small	O
change	O
in	O
the	O
message	O
will	O
(	O
with	O
overwhelming	O
probability	O
)	O
result	O
in	O
a	O
mostly	O
different	O
hash	B-Algorithm
,	O
due	O
to	O
the	O
avalanche	O
effect	O
.	O
</s>
