International Association
for Cryptologic Research

This paper describes the first construction of efficient identity-based broadcast encryption (IBBE) schemes which

can be proved secure against adaptive-identity attacks based on standard assumptions. The constructions are

obtained by extending the currently known most efficient identity-based encryption scheme proposed by Jutla

and Roy in 2013. Ciphertext size and user storage compare favourably to previously known constructions. The

new constructions fill both a practical and a theoretical gap in the literature on efficient IBBE schemes.