Practical Deniable Encryption 

       M. Klonowski, P. Kubiak, and M. Kutylowski

A party using encrypted communication or storing data 
in an encrypted form might be forced to show the corresponding plaintext. 
It may happen for law enforcement reasons as well as for evil purposes.
Deniable encryption scheme introduced by Canetti et al. shows 
that  cryptography can be used against revealing information: 
the owner of the data may decrypt it in an alternative way
to a harmless plaintext. Moreover, it is impossible to check 
if there is another hidden plaintext.

The scheme of Canetti is inefficient in the sense 
that it is a special purpose scheme and using it indicates 
that there is some hidden message inside. We show that deniable encryption 
can be implemented in a different way so that it does not point 
to deniable encryption. Moreover, it is quite straightforward, so
it can be used for both good and evil purposes.

Apart from that we show that even the special purpose original
scheme can be extended to allow any ``depth'' of deniability

* Current Trends in Theory and Practice of Computer Science (SOFSEM) 2008
To appear in LNCS, Springer-Verlag