Information Technology Reference
In-Depth Information
A Group Signature Scheme Based on the Integer
Factorization and the Subgroup Discrete
Logarithm Problems
R. Duran D ıaz 1 ,L.Hernandez Encinas 2 ,andJ.Munoz Masque 2
1 Universidad de Alcala, 28871-Alcala de Henares, Spain
raul.duran@uah.es
2 Instituto de Fısica Aplicada, CSIC, 28006-Madrid, Spain
{ luis,jaime } @iec.csic.es
Abstract. Group signature schemes allow a user, belonging to a specific
group of users, to sign a message in an anonymous way on behalf of the
group. In general, these schemes need the collaboration of a Trusted
Third Party which, in case of a dispute, can reveal the identity of the
real signer. A new group signature scheme is presented whose security is
based on the Integer Factorization Problem (IFP) and on the Subgroup
Discrete Logarithm Problem (SDLP).
Keywords: Digital signature, Group signature, Public key cryptography.
1
Introduction
As it is well-known, there are different protocols to determine digital signatures.
In general, these protocols are based on public key cryptosystems [1,2,3]. The
main characteristic of this signature schemes is that each signer has one public
key and one private key.
Moreover, the procedures of digital signatures are made more ecient if hash
functions are used [4]. The hash functions are public and they allow to sign a
digest or hash of the message.
Group signature schemes were proposed by Chaum and van Heyst in 1991 [5].
These schemes permit a signer group to sign a given message such that only a
member of the group computes the signature on behalf of the whole group. A
Trusted Third Party (
) collaborates in the generation of the keys and is able
to reveal the identity of the user who signed the message, if a dispute arises.
The main characteristics defining the group signatures are the following:
T
1. Only a member of the signer group signs the message.
2. The receiver of the message can verify that the signature of the message was
generated by a member of the signer group, but he cannot determine which
member of the group was the signer.
3. If a dispute arises, it is possible to open the signature in order to determine
who was the actual signer of the message.
 
Search WWH ::




Custom Search