Simple and efficient group signature scheme assuming tamperproof devices

Abstract

We propose a simple and efficient group signature scheme assuming tamperproof devices, which is based only on the DDH assumption and the Random Oracle. Compared to the state-of-the-art group signature schemes of [9, 13, 15], although the proposed scheme does not have coalition resistance and exculpability thus requires tamperproof devices, it is about twice faster in signature generation in exchange. It is also efficient in signature size and signing key size. Even though the application of the proposed scheme is not extensive, it can be much more suitable than previous schemes for platforms with tamperproofness and limited resources such as smart cards or mobile phones. Our approach is important in designing group signature schemes (with some restrictions) in the sense that it has shown a concrete construction that one can build a better scheme by carefully considering redundant properties for required security level of given platform. The proposed scheme also supports Verifier Local Revocation, Self-Traceability and weaker version of Non-Frameability. © 2008 Springer Berlin Heidelberg.