Aggregating CL-Signatures Revisited: Extended Functionality and Better Efficiency.
Kwangsu Lee, Dong Hoon Lee, Moti M. Yung · 2012
Aggregate signature is public-key signature that allows anyone to aggregate different signatures gen-erated by different signers on different messages into a short (called aggregate) signature. The notion has many applications where compressing the signature space is important: secure routing protocols, compressed certificate chain signature, software module authentications, and secure high-scale reposito-ries and logs for financial transactions. In spite of its importance, the state of the art of the primitive is that it has not been easy to devise a suitable aggregate signature scheme that satisfies the conditions of real applications, with reasonable parameters: short public key size, short aggregate signatures size, and efficient aggregate signing/verification. In this paper, we propose aggregate signature schemes based on the Camenisch-Lysyanskaya (CL) signature scheme (Crypto 2004) whose security is reduced to that of CL signature which substantially improve efficiency conditions for real applications. • We first propose an efficient sequential aggregate signature scheme with the shortest size public key, to date, and very efficient aggregate verification requiring only a constant number of pairing operations and l number of exponentiations (l being the number of signers). • Next, we propose an efficient synchronized aggregate signature scheme with a very short public