<s>
In	O
cryptography	O
,	O
Spectr-H64	B-Algorithm
is	O
a	O
block	O
cipher	O
designed	O
in	O
2001	O
by	O
N	O
.	O
D	O
.	O
Goots	O
,	O
A	O
.	O
</s>
<s>
It	O
relies	O
heavily	O
on	O
the	O
permutation	B-Algorithm
of	O
individual	O
bits	O
,	O
so	O
is	O
much	O
better	O
suited	O
to	O
implementation	O
in	O
hardware	O
than	O
in	O
software	O
.	O
</s>
<s>
It	O
uses	O
a	O
12	O
round	O
structure	O
in	O
which	O
half	O
of	O
the	O
block	O
determines	O
the	O
transformation	O
of	O
the	O
other	O
half	O
in	O
each	O
round	O
,	O
similar	O
to	O
a	O
Feistel	B-Algorithm
cipher	I-Algorithm
or	O
RC5	B-Algorithm
.	O
</s>
<s>
This	O
same	O
basic	O
design	O
was	O
repeated	O
in	O
its	O
successor	O
,	O
CIKS-1	B-Algorithm
.	O
</s>
<s>
An	O
analysis	O
of	O
Spectr-H64	B-Algorithm
was	O
presented	O
in	O
2002	O
by	O
Selçuk	O
Kavut	O
and	O
Melek	O
D	O
Yücel	O
of	O
the	O
Middle	O
East	O
Technical	O
University	O
,	O
showing	O
a	O
method	O
of	O
using	O
a	O
differential	O
attack	O
to	O
retrieve	O
half	O
of	O
the	O
key	O
bits	O
when	O
a	O
single	O
round	O
is	O
used	O
.	O
</s>
