<s>
In	O
cryptography	O
,	O
format-transforming	B-Application
encryption	I-Application
(	O
FTE	O
)	O
refers	O
to	O
encryption	O
where	O
the	O
format	O
of	O
the	O
input	O
plaintext	O
and	O
output	O
ciphertext	O
are	O
configurable	O
.	O
</s>
<s>
Descriptions	O
of	O
formats	O
can	O
vary	O
,	O
but	O
are	O
typically	O
compact	O
set	O
descriptors	O
,	O
such	O
as	O
a	O
regular	B-Language
expression	I-Language
.	O
</s>
<s>
Format-transforming	B-Application
encryption	I-Application
is	O
closely	O
related	O
to	O
,	O
and	O
a	O
generalization	O
of	O
,	O
format-preserving	B-Algorithm
encryption	I-Algorithm
.	O
</s>
<s>
Similar	O
to	O
format-preserving	B-Algorithm
encryption	I-Algorithm
,	O
FTE	O
can	O
be	O
used	O
to	O
control	O
the	O
format	O
of	O
ciphertexts	O
.	O
</s>
<s>
FTE	O
is	O
used	O
by	O
the	O
Tor	O
Project	O
to	O
circumvent	O
deep	B-Application
packet	I-Application
inspection	I-Application
by	O
pretending	O
to	O
be	O
some	O
other	O
protocols	O
.	O
</s>
