Lightweight devices, such as a smartcard associated with a top‐box decoder in pay‐TV or a
SIM card coupled with a powerful (but not totally trusted) smartphone, play an important role
in modern applications. The essential requirements for a cryptographic scheme to be truly
implemented in lightweight devices are that it should have compact secret key size and
support fast decryption. Attribute‐based broadcast encryption (ABBE) combines the
functionalities of both broadcast encryption and attribute‐based encryption in an efficient …