Threshold proxy re-signature: definition and new constructions

AbstractThe previous threshold proxy re-signature schemes have been mainly constructed with bilinear maps, the implementations of which are much more time-consuming than exponentiation operations. To solve this problem, we propose efficient threshold proxy re-signature schemes which are constructed with El-Gamal signatures. The performance analysis shows that our schemes are more efficient than the existing threshold proxy re-signature schemes. Based on the discrete logarithm problem, our schemes are provable secure in the random oracle model.