Step-out Ring Signatures
Marek Klonowski, Lukasz Krzywiecki,  Miroslaw Kutylowski, and  Anna Lauks
       
              Institute of Mathematics and Computer Science
                      Wroclaw University of Technology

We propose a version of ring signatures for which  the set of potential signers
may be reduced: the real  signer  can prove that he or she has created the signature, 
while every other member of the ring can prove not to be the signer. Possibility 
to run these protocols is triggered by publishing certain secret information.
The proposed scheme is an intermediate solution between the classical ring  and 
group signatures, and can be used for instance for e-auction schemes. 


Partially supported by Polish Ministry of Science and Higher Education, grant N~N206~2701~33
published in  MFCS'2008