International Association
for Cryptologic Research

This paper demonstrates new technique for managing revocation in the context of

attribute-based encryption (ABE) and presents two selectively secure directly revocable ABE (RABE)

constructions

- supporting decryption policies realizable by polynomial size Boolean circuits of arbitrary fan-out

and

- featuring compactness in the sense that the number of revocation controlling components in

ciphertexts and decryption keys are constant.

In fact, our RABE schemes are the first to achieve these parameters. Both our constructions utilize

multilinear maps. The size of public parameter in our first construction is linear to the maximum

number of users supported by the system while in the second construction we reduce it to logarithmic.