A proposal of short proxy signature using pairing

In this paper, we propose a new pairing-based proxy signature. Most remarkable point in our proposal is that our scheme realizes short signature. More concretely, the explicit proxy signature consists of only one parameter. This means that the size of signature is reduced to at least half-size compared to previous schemes. Amount of work for proxy signature generation is also small. Although some previous schemes such as Boneh-Lynn-Shacham (2001) or Hess (2002), need a special hash function, our scheme does not require such a function. This means that our scheme can use general hash function, e.g., SHA-1. To construct our scheme, we propose a new problem named the (extended) k-plus problem. We also propose a short signature scheme which has satisfactory properties from the point of efficiency.