Abstract: Aiming at the classic LR98 group blind signature scheme, this paper analyses its security and efficiency, then finds that LR98 scheme uses fixed value l as security parameter, this leads to the group public key and signature length having linear relationship with the size of group, so its calculated complex degree, space complex degree and communication complex degree have linear relationship with l, therefore the original scheme efficiency is low. The improved scheme proposed in this paper improves efficiency by selecting new security parameter.

Key words: group blind signature, information security