Stanford Technology Ventures Program
The authors surveyed two techniques for signature aggregation. Both methods provide the ability to compress multiple signatures by distinct signers on distinct messages into a single signature. The first method, based on bilinear maps, provides general aggregation, where anyone can combine signatures into an aggregate at any time, without the cooperation of the signers. The second method, based on homomorphic trapdoor permutations such as RSA, provides only sequential aggregation where aggregation must be done during the signing process. General aggregation is more a powerful mechanism than sequential aggregation. For example, sequential aggregation can be built from general aggregation. Also, general aggregation seems easier to use.