Affiliations: Department of Mathematics, Inha University, Yonghyun-dong 253, Nam-gu, Incheon, 402-751, Korea, e-mail: [email protected], [email protected], | Department of Mathematics, Ewha Womans University, Daehyun-dong 11-1, Seodaemun-gu, Seoul, 120-750, Korea, e-mail: [email protected] | KISA, IT Venture Tower, Garak-dong 78, Songpa-gu, Seoul, 138-950, Korea, e-mail: [email protected]
Note: [] This work was supported by Priority Research Centers Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009-0093827).
Abstract: Batch cryptography has been developed into two main branches – batch verification and batch identification. Batch verification is a method to determine whether a set of signatures contains invalid signatures, and batch identification is a method to find bad signatures if a set of signatures contains invalid signatures. Recently, some significant developments appeared in such field, especially by Lee et al., Ferrara et al. and Law et al., respectively. In this paper, we address some weakness of Lee et al.'s earlier work, and propose an identification method in an RSA-type signature. Our method is more efficient than the well known divide and conquer method for the signature scheme. We conclude this paper by providing a method to choose optimal divide and conquer verifiers.
