Generic On-line/Off-line Aggregate Signatures

Aggregate signatures play an important role in many real-world applications involve signatures on many different messages generated by many different users. However, the existing aggregate signature schemes are unsuitable for the environments where the computing and storage resources are limited since it always involves in inefficient modular exponentiation or pairing operations in aggregate signing or verification algorithms. In this paper we introduce the concept of on-line/off-line aggregate signatures in order to improve the performance of aggregate signatures. We also use an efficient double-trapdoor chameleon hash function to present a concrete construction based on the so-called ldquohash-sign-switchrdquo paradigm. Moreover, we give an application of our scheme in stock markets, where the stockbroker can compress and batch verify the stockholderspsila signatures in time due to the on-line/off-line property.