Black-box accountable authority identity-based encryption

Abstract

A well-known concern in the setting of identity based encryption is that the PKG is all powerful and has to be completely trusted. To mitigate this problem, the notion of Accountable Authority Identity-Based Encryption (A-IBE) was recently introduced by Goyal. Goyal provided constructions to realize the notion of A-IBE only in the white box and weak black box models. However, the security guarantees provided by these models fall short of those required in practice.